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SEPARATION-INDIVIDUATION IN TWINS:
AN OBJECTIVE ASSESSMENT

By

Elizabeth Jill Hirt

A DISSERTATION

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

DOCTOR OF PHILOSOPHY

Department of Counseling and Educational Psychology

1980

m/ 6 6’?/

© Copyright by

ELIZABETH JILL HIRT

1980

ii

ABSTRACT

SEPARATION-INDIVIDUATION IN TWINS:
AN OBJECTIVE ASSESSMENT.

By

Elizabeth Jill Hirt

The purpose of this study was to assess any differences in the
separation-individuation process between twins and non-twins, and to
validate a revised objective measure of separation-individuation. It
was postulated that significant differences between twins and non-twins,
and among differing twin-types, would provide evidence for the validity
of the measure of separation-individuation, and enlarge the field of
knowledge concerning adult twins.

The sample in this study included 40 non-twins, 40 identical twins,
40 fraternal same-sex twins, and 40 fraternal opposite-sex twins. All
of the participants were volunteers, college students, and between the
ages of 18 and 25. Each completed the separation-individuation instru-
ment, which consisted of five subscales, and a background questionnaire,
which inquired about the respondents' relationship with the twin or
closest sibling. It was hypothesized that twins would exhibit less
complete separation-individuation than fraternal twins, and that
fraternal same-sex twins would exhibit less complete separation-

individuation than fraternal opposite-sex twins.

Elizabeth Jill Hirt

The data were analyzed with a Efratio of planned orthogonal
comparisons, with the probability of significance set at the .05 level.
The comparisons between identical and fraternal twin mean scores on the
five subscales of the separation—individuation instrument, and the
comparisons between fraternal same-sex and fraternal opposite-sex
twin mean scores on the five subscales of the separation individuation
instrument, were not significant. However, comparisons between non-
twin and twin mean scores on the five subscales revealed a significant
difference on the Individuation II-Present subscale, indicating a
difference between twins and non-twins in the areas of dependency,
jealousy, and guilt. On the other four subscales, there were no signi-~
ficant differences.

Based upon an examination of the respondents' answers to the
questions concerning the relationship to the twin (which included such
items as to whether the parents emphasized the similarities or differ-
ences between the twins, and the frequency of alliterative names,
dressing alike, or a secret language between the twins), it was found
that most of the twins used in this study did not represent, in general,
the twins reported in the literature, and upon which the separation-
individuation process in twins was developed. The theory on which
separation-individuation in twins and the intertwin relationship is
based seems to come from twins who have multiple problems, e.g., parents
initially had difficulty distinguishing one twin from the other, and
encouraged the similarities between the twins, giving them alliterative
names and dressing them alike; between the twins, there was considerable
rivalry and competition, feelings of being one-half of a whole, and an

inability to separate from the twin. However, the parents of the twins

Elizabeth Jill Hirt

used in this study apparently emphasized the differences rather than
the similarities between the twins when they were young; most of the
twins did not dress alike currently, although they did when they were
younger; and most were not living with or attending the same school as
the twin. In brief, the twin sample used in this study does not appear
to suffer from the complicating and diverse psychological difficulties
that were evidenced by the individuals in much of the literature on
twins. While there are twins who do have difficulty in the separation-
individuation process, it appears as if not all twins have these

problems.

DEDICATION

To Nana

iii

ACKNOWLEDGEMENTS

There are a number of people whose assistance and kind interest
have made this dissertation a reality. For their reviewing, editing,
and critiquing of this study, I would like to thank Norman Stewart,
committee chariman, and John Schweitzer, Herbert Burks, and
Thomas Stachnik, committee members. I would like to thank
Cassandra Simmons for her encouragement, and Len Bianchi for his
considerable assistance with the design and analysis of the data.

I would also like to express my appreciation for the invaluable
personal and financial support provided by Robert Green and the College
of Urban Development. Through him and the opportunities provided by
the College, my education was broadened to include the real world,
which, due to some of the constraints of being a graduate student,
sometimes did not seem to exist.

My appreciation is also extended to my family: my twin sister
Jane, who, perhaps unknowingly, in some way inspired this research;
my younger sister Judy; my brother Bill; and my parents, Carl and
Betty.

Finally, I would like to pay a special tribute to Karen Maroda,

a very dear friend and colleague. She offered intellectual sustenance
in what at times seemed an academic wasteland, reassurance in times of
self-doubt, and a perspective, humorous and otherwise, which enabled

me not to take myself so seriously. As a colleague, she was

iv

genuinely interested in this research, and her consultation and

assistance meant more to me than words can ever express.

TABLE OF CONTENTS

LIST OF TABLES. . . . . . . . .

CHAPTER

I.

II.

III.

IV.

THE PROBLEM.

Need .

Purpose. . . . . . . .

Theory . . . . . . . .
Types and Frequencies of Twins . .
Research Questions .

Overview . . . . . .

REVIEW OF THE LITERATURE .

Parental Reactions to Twins.
The Intertwin Relationship .
Intertwin Identification .
Rivalry and Ambivalence .
Complementary Relationships.
Separation from the Twin . . . . . . . .
Differences between Twins and Non-twins.

Systematic Studies of the Twin Relationship.

Discussion . . . . . .
Summary. . . . . . . . . . . . . . . .

DESIGN AND METHODOLOGY .

_Sample . . .

Instrumentation. . . . . .
Separation-Individuation Instrument.
Background Questionnaire . . . . .

Procedure. . . . . . . . . . .

Analysis . . . . .

Hypotheses .

Summary.

RESULTS. . . . . . . .

Hypotheses Tests . . . . . . . .
Additional Results . . . . . .

Descriptive Material on Twins and Non-twins.

vi

Page

viii

16

20
27
27
36
40
44
47
48
52
54

55

55
57
57
63
65
67
67
68

69
71

75
85

Frequency of Alliterative Names. . . . . . . . . . . . .
Frequency of Dressing Alike. . . . . . . . . . . . . . .

Frequency of a Secret Language . . . . . . . . . . . . .
Closeness to the Parents . . . . . . . . . . . . . . . .
Closeness between Twins and Non—twins. . . . . . . .

Parental Emphasis of Similarities or Differences
between Twins. . . .
Feelings about Being a Twin.
Summary. . . . . . . . . . . . . . . . . . . . . . . . . .

SUMMARY AND CONCLUSIONS.

Summary. . . . . . . . . . . . . .

Discussion . . . . . . . . . . . . . . . . . . . . . .
Implications for Further Research. . . . . . .
Implications for Counseling and Counseling Practice.

In Retrospect.
APPENDICES
A. Posted Sign to Recruit Twins for the Study .

B.

J.

K.

Newspaper Advertisements to Recruit Twins for the Study.
Separation-Individuation Instrument, Form A. .
Separation-Individuation Instrument, Form B.

Background Questionnaire Used with Separation-Individuation
Instrument, Form B . . . . . . . . . . . . . . . . .

Clusters Derived from Separation—Individuation Instrument,
Form B O O O O O O O O O I O O O O O O O O O O O O O 0

Standard Score Coefficient Alphas and Communalities in
the Diagonal for the Five Clusters .

Separation-Individuation Instrument, Form C.
Twin Background Questionnaire Used for Twin Sample .
Background Questionnaire Used for Non-twin Sample.

Directions for Completion of Instruments .

REFERENCES.

vii

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88
92
92
95
96

100
102
102
103
114

116
118

119
120
121

128

133

135

141
147
153
157
158

161

Table
2.1

LIST OF TABLES

Systematic Studies of the Twin Relationship. . . . . . . .
Demographic Information on the Complete Sample . . . . .
Demographic Information on the Sample by Twin-type .

Cell Means and Standard Deviations by Twin-type on the
Five Subscales of the Separation-Individuation
Instrument . . . . . . . . . . . . . . . . . . .

Cell Means and Tests of Significance of Differences
between Non—twins (NT) and Twins (T) on the Separation-
Individuation Instrument . . . . . . . . . . .

Cell Means and Tests of Significance of Differences
between Identical Twins (ID) and Fraternal Twins (F)
on the Separation-Individuation Instrument . . .

Cell Means and Tests of Significance of Differences
between Fraternal Same-sex Twins (F88) and Fraternal
Opposite—sex Twins (FOS) on the Separation-Individuation
Instrument . . . . . . . . . . . . . . . . .

Cell Means and Standard Deviations for All Subjects
on the Five Subscales of the Separation-Individuation
Instrument on the Variable of Childhood Fear of
Going to School. . . . . . . .

Analysis of Variance on Childhood Fear of Going to
School as a Child for All Subjects on the Five Sub-
scales of the Separation-Individuation Instrument.

Cell Means and Standard Deviations for All Subjects on
the Five Subscales of the Separation-Individuation
Instrument on the Variable of Missed School as a Child .

Analysis of Variance on Missed School as a Child for

All Subjects on the Five Subscales of the Separation-
Individuation Instrument .

viii

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58

59

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72

73

74

77

78

79

80

4.9

5.1

Cell Means and Standard Deviations for All Subjects on
the Five Subscales of the Separation—Individuation
Instrument on the Variable of Sex. . . . . . .

Analysis of Variance on Sex for All Subjects on the
Five Subscales of the Separation-Individuation
Instrument O O O O O O O O O O O O O O O O 0

Cell Means and Standard Deviations for All Subjects on
the Past Subscale of the Separation-Individuation
Instrument . . . . . . . . . . . . . . . .

Analysis of Variance on Currently Dressing Alike for
All Subjects on the Past Subscale of the Separation-
Individuation Instrument . . . . . .

Frequency of Alliterative Names by Twin—type and Sex .

Frequency of Dressing Alike in Elementary School by
Twin-type and Sex. . . . . . . . . . . . . .

Frequency of Dressing Alike in High School by Twin-
type and Sex . . . . . . . . . . . . . . . . .

Frequency of Currently Dressing Alike by Twin-type and
Sex . . . . . . . . . . . . . . . . . . . . . .

Frequency of a Secret Language by Twin-type and Sex.

Frequency of Closeness to the Same or Different Parent
by Twin-type . . . . . . . . . . . .

Cell Means and Standard Deviations on the Variable of
Closeness to the Twin/Closest Sibling at the Present
Time by Twin-type. . . . . . .

Cell Means and Standard Deviations on the Variable of
Closeness to the Twin/Closest Sibling at the Present
Time by Twin-type and Sex.

Frequency of Parental Emphasis of Similarities or
Differences between Twins by Twin-type .

Frequency of Feelings Concerning Being a Twin for the
Total Twin Sample. . . . . . . . .

Frequency of Feelings Concerning Being 3 Twin by
TWin-type o o o o o o o o 0

Summary of Significant Findings.

ix

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104

CHAPTER I

THE PROBLEM

gfiggi

While many studies have been conducted on the psychology of twins,
most of them have focused on the question of nature v. nurture, with a
particular emphasis on intelligence and schiZOphrenia. These studies
typically involve the measurement of one or another characteristic in
pairs of twins, and correlations or concordance rates are examined to
determine whether the characteristic under investigation has been
inherited or acquired from the environment.

Studies in the area of personality research involving relation-
ships between twins were reported in the early 19303 by von Bracken
(1934), Hartmann (1934-35/1964), and Cronin (1933). Following
World War II, there was a mild, renewed interest in twins; Burlingham
published her classic study on three pairs of identical twins in 1952,
but it was not until the 19605 that the intertwin relationship began
to be studied in more detail. Most of the literature, however, consists
of isolated case studies of fraternal and identical twins; very few
researchers have compared fraternal and identical twins, and even
fewer have compared twins to non-twins. In addition, while many
researchers have noted the "uniqueness" of the twin relationship, and
how some twins feel the need to recreate the twin relationship with

other persons, none have systematically examined the nature or extent

2
of this need. Thus, little is known about how the relationships
with other people differ between twins and non-twins. The literature
on twins also seems to be largely restricted to twins in therapy, or
those in some type of crisis situation. This phenomenon naturally
restricts the generalizability of the findings, and may provide too
narrow a viewpoint when examining twins in the general population.

Lastly, while many researchers or theorists have proclaimed that
there seems to be a problem for twins, dating from birth, in the
separation-individuation process, none have studied adult twins to
determine if this problem does in fact continue into adulthood. Those
studies that have been conducted pertaining to these issues have
involved observational and/or subjective psychoanalytic techniques and
have been concentrated on children from infancy to school age. There-
fore, using a young adult population would expand the age range of
twins studied thus far, as well as confirm the persistence of early
separation-individuation problems in adulthood.

Maroda (1979) provided preliminary evidence for the use of
objective methods for assessment in the area of separation-individuation.
Additional studies using adult twins would further substantiate her
hypotheses regarding the separation-individuation process in adults,
as well as provide valuable information on the differences between

twins and non-twins in the separation-individuation process.

Purpose

The purpose of this study, then, is to (a) validate a revised
objective measure of separation-individuation; (b) assess the extent of

separation-individuation in twins as compared to non-twins; and

(c) assess the extent of separation-individuation in identical twins as
compared to fraternal twins.

Outcomes showing twins to have greater difficulty than non-twins
in the separation-individuation process, and identical twins to have
greater difficulty than fraternal twins, would both validate the
objective test of separation-individuation utilized as the criterion
variable in this study, and support the literature pertaining to

separation-individuation in twins.

Theory

The separation-individuation process is the process whereby the
infant becomes separate from the mother and is able to function in a
relatively independent manner. Separation-individuation refers to
two interdependent and complementary kinds of development: separation
concerns the intra-psychic process in which the mother comes to be per-
ceived as separate from the self, while individuation centers around
the child's developing self—concept (McDevitt, 1975). While as an adult
the ability to see oneself as being both "in" and at the same time
separate from the world "out there" is taken for granted, it is a result
of a gradual sequence of events which begin at birth and continue
throughout the life cycle (Mahler, 1972b). The initial psychological
achievements in this process occur from about the fourth to the thirty-
sixth month.

During the first few weeks of life, the infant is in a state of
"primitive hallucinatory disorientation," or what Mahler (1968) terms
a state of normal autism. The infant does not perceive the mother as

being a separate and distinct entity, and his/her waking life centers

around an attempt to achieve and maintain biological homeostasis.

This state gradually gives way, at about the second month, to normal
symbiosis, during which time the infant becomes vaguely aware of the
need-satisfying object. However, there is no real differentiation
between the "I" and "not I"; " . . . the infant behaves and functions
as though he and his mother were an omnipotent system, a dual unity
within one common boundary" (Mahler, 1968, p. 488).

Following this period, the infant begins "hatching out" from the
dual symbiotic unit. Whereas the infant's attention was previously
directed inward and focused within the symbiotic orbit, it now becomes
outwardly directed (Mahler, 1972a). The child emerges from symbiosis,
and at about the fourth or fifth month, smooth differentiation from the
mother's body can begin to take place. This development marks the
beginning of the separation-individuation process.

It is during this subphase of differentiation that the infant,
through the maturation of sensory and motor capabilities, takes the
first tentative step toward breaking away, in a bodily sense, from the
mother. The child will, for example, slide from the mother's lap, but
will tend to remain as near as possible to her. Also, it is at this
stage that the specific smiling response to the mother, signalling
a specific bond between mother and child, occurs.

The second subphase, practicing, begins at about seven months.
Actually, there are two stages in this period. The early practicing
subphase (which overlaps to some degree with differentiation) is
characterized by the infant's moving away from the mother while still
returning to her for occasional "emotional refueling" (Furer,

unpublished, cited by Mahler, 1972b). The second part is characterized

by upright locomotion, and it is during this period (from about 10 to
18 months) that the infant's "love affair" with the world begins. The
child is " . . . intoxicated with his own faculties and with the great-
ness of the world . . . . The chief characteristic of this practicing
period is the child's great narcissistic investment in his own functions,
his own body, as well as in the objects and objectives of his expand—
ing 'reality'" (Mahler, 1972b, p. 491). This period culminates at about
18 months, at which time the child is at the peak of his magic omni—
potence and at the height of his ”ideal state of self" (Mahler, 1968).

However, it soon occurs to the infant that the world is in fact
not his oyster, and that he/she must cope with it as a rather small,
helpless, and separate individual. "The toddler now begins to experi-
ence, more or less gradually and more or less keenly, the obstacles that
lie in the way of his anticipated 'conquest of the world'" (Mahler,
1972a, p. 337). The relative lack of interest in the mother during the
practicing period is now replaced by active approach behavior, a
constant concern with the mother's whereabouts, and anxiety when
separated from the mother. The infant, with increasing realization of
his/her separateness, seems to have an increased need and wish for the
mother to share every new experience and development. This subphase of
rapprochement(from about 15 to 22 months) is thus a period of vulnera—
bility; it is, as Mahler (1968) states, a " . . . time when the child's
self-esteem may suffer abrupt deflation" (p. 121).

The child at this stage must relinquish the delusions of grandeur,
and frequently, dramatic fights with the mother occur; Mahler terms this
the "rapprochement crisis" (1972b). At this juncture, despite the fact

that the child is becoming increasingly autonomous in his/her actions

relative to the mother, attempts are simultaneously made to resist the
separation from the mother. However, both mother and child must
realize that they can no longer function as a dual symbiotic unit.

When the rapprochement crisis is resolved, the child enters the
last subphase, individuation and object constancy. The chief criterion
is the ability of the child to tolerate brief separations from the
mother, an ability which results from the emergence of a stable mental
representation of the mother; prior to this time, she was only
available physically (Mahler, Pine, & Bergman, 1975). This "internal
mother" is more or less available in order to supply comfort to the
child in the mother's physical absence. There is also a shift from self-
centered, demanding, clinging behaviors to more mature, ego-determined
relationships; this includes expressions of affection, trust, confi-
dence, and the ability to interact with others in a cooperative and
understanding manner (McDevitt, 1975).

The mother's reactions to this entire sequence of events is of
critical importance. She can act either as a facilitator or inhibitor
of the separation-individuation process, and the role that she selects
has a direct impact on the child's ability to perceive him/herself as a
separate, distinct, and capable individual in a safe and nonthreatening
environment. Some mothers may not welcome the separation from the
symbiotic unit, or they may find it difficult to find a natural and
optimal balance between providing active support for the child and, at
the same time, knowing when to merely be available and observe from a
distance.

The mother will react according to whether she feels that her child

is merely an extension of herself or a separate individual. As soon as

a child begins to act autonomously, e.g., in the practicing subphase,
some mothers fail their infants prematurely by "abandoning" them to
their own devices. "They react with a kind of relative ridding mecha-
nism to the traumatization of their own symbiotic needs" (Mahler, 1968,
p. 119). Other mothers do not adequately respond to the infant's desire
to be separate and, at the same time, to be attached.

Mark was one of those children who had the greatest difficulty in
establishing a workable distance between himself and mother. His
mother was ambivalent as soon as Mark ceased to be part of herself,
her symbiotic child. At times she seemed to avoid close body con-
tact; at other times she might interrupt Mark in his autonomous
activities to pick him up, hug him and hold him. She did this,

of course, when she needed it, not when he did. This ambivalence
on mother's part may have been what made it difficult for Mark to
function at a distance from his mother. (Mahler, 1972a, pp. 336-
337)

Conflict is also evident in the rapprochement subphase. The
infant, somewhat indifferent to the mother during the practicing sub-
phase, now returns to the mother constantly so that she can share in
every new discovery and accomplishment. Again, the mother can facili-
tate the toddler's growing autonomy, or she can act as a barrier.

From the data we have accumulated so far, we would state strongly

that the mother's continued emotional availability is essential

if the child's autonomous ego is to attain optimal functional
capacity. . . . . However, the less emotionally available the
mother has become at the time of rapprochement, the more
insistently and even desperately does the toddler attempt to

woo her. In some cases, the process drains so much of the child's

available developmental energy that, as a result, not enough may

be left for the evolution of the many ascending functions of
the ego. (Mahler, 1972b, pp. 495-496)

This concludes the discussion of the separation-individuation process
in singly-born children. For twins, separation-individuation is some—
what complicated in that each twin must not only separate from the
mother and establish his/her own identity, but must also separate from

the twin, and find an identity in relationship to his/her twin.

8

As individuals, each twin goes through the same developmental
processes as non-twins. They go through the undifferentiated phase in
which ego and id are one, and no boundaries exist between the self and
the outside world. There is an initial sense of oneness, or lack of
perception of separateness, with the twin, just as there is with the
mother. The maturation of sensory perception is necessary before one
twin can perceive him-/herself to be separate from the other. Leonard
(1961), for example, describes the lack of physical differentiation in
a set of twins at three months of age.

Twins . . . were lying side by side in a twin-sized baby carriage.

Both infants were sleeping peacefully on their backs, the thumb
of one twin in the mouth of the other. (p. 307)

Twins become aware of each other in the differentiation subphase.
Burlingham (1952), in her study of three pairs of identical twins, found
that Bert and Bill responded to the mother before responding to each
other, as did Bessie and Jessie, and that both responded at about seven
months.

The development of the infant—mother relationship is somewhat
circumvented and hindered by the presence of twins; 3 twin never experi—
ences the luxury of the singly-born child of being the sole recipient of
the mother's attention (Leonard, 1961). At the earliest stages of
development, twins react to their mothers as singly-born children do,
but even at early stages, the twins become aware of providing pleasure
not as separate and distinct individuals, but as a unit. The mother may
encourage independence and separateness from her, but her actions may,
not infrequently, prompt the twins to seek the companionship of each
other. Because of the mother's household, career, and other responsi-

bilities, and especially if the twins get along with each other fairly

well, they are frequently left to entertain each other. In addition,
even when the twins are with the mother, it is not uncommon for imita-
tion to occur, i.e., when one twin reacts emotionally to the mother,
the other will imitate these reactions as well. It is this imitation,
which is based on identification with the twin, that leads to identity
problems in twins.

Although the concept of identification was not mentioned in the
previous discussion of separation-individuation, it is identification
which sustains the individuating infant against the continuous danger
of feelings of helplessness. In the separation-individuation process,
with the beginning awareness of separateness comes the first stage in
the process of identification: striving to maintain unity with the
pleasure-giving object through incorporating it into the ego, or primary
identification.

Whenever he (the child) drinks from his mother's breast or is

physically close to her body, his wishful fantasies of reunion

with the mother by means of oral incorporation will be grati-
fied. Hence with the achievement of gratification, his images

of the self and of the love object will temporarily merge, only

to be separated again with the increase of instinctual needs

and experiences of hunger and frustration . . . . (Jacobson,
1954, pp. 98-99)

Normally, the child progresses from the primary identification with

the mother to a more active type of primitive identification through
imitation of the mother. Self-images that result from identification
may have either the person or function as the principal motif
(Lichtenberg, 1975). In other words, self-images may arise from per-
ceptual images of a particular person, for example, from a mother's
loving smile, or perceptual images of functions, in which there is less

emphasis on personal characteristics. An example of the latter would

10

be the child's internalization of the function of soothing, which is
evident in a child's symbolic play when he/she may, for instance, mother
a doll to comfort him—lherself when mother is absent.

Identification between the twins is usually mutual, i.e.,
reciprocal and of equal intensity. Continued visual confrontation with
the mirror image of the twin leads to identification through visual
incorporation, and this identification resembles the primary identifica-
tion with the mother in many respects (Leonard, 1961). Imitation of
both language and action is quite frequent. In Burlingham's (1952)
study, Bill and Bert imitated each other's movements and gestures from
12 months of age. While both of them were constantly trying to find
ways of entertaining each other, such copying games hindered them from
making normal contacts with others. Another pair, Jessie and Bessie
(aged two years), both made identical and innumerable demands on their
mother, and would not accept any refusal on the part of the mother to
accede to their demands. All three sets of twins that Burlingham
observed worked as a team to either provoke the mother, or in their
copying games, to entertain each other. At such times, they were
exclusively occupied with each other and were not amenable to outside
influence. They frequently combined against parental or other authority
figures, and when they experienced some type of disappointment, they
clung together, falling back on their relationship to each other.

This exclusive and dependent relationship between the twins soon
becomes self-perpetuating:

One aspect of this becomes clear: there is a tendency for the

primary intertwin identification to be self-perpetuating. Once

it has become intensified, it inhibits progress toward communica-

tion with individuals other than the twin and thus hinders the
development of object relationships. (Leonard, 1961, p. 313)

11
There is an increasing influence of one upon the other, and the stage
is set for the twins to identify with each other rather than with an
adult object. As Ortmeyer (1970) found, "they may not struggle toward
individuation, but replace the mother with each other" (p. 138).

For twins and non-twins, normal separation-individuation is the
first crucial prerequisite for the development and maintenance of the
sense of identity (Mahler, 1963). The evolution of the sense of self
is a gradual process: initially, self-representations are fused and
confused with object representations, but with advances in ego
development, maturation of physical abilities, and the development of
the capacity for perception, self-perception, and introspection, the
images become unified and organized into more or less realistic con-
cepts of the self and others (Jacobson, 1954). However, this does not
mean that at the age of 36 months a stable image of the self emerges
and is maintained, without alteration, throughout the remainder of the
individual's life.

One could regard the entire life cycle as constituting a
more or less successful process of distancing from and intro-
jection of the lost symbiotic mother, an eternal longing for the
actual or fantasied 'ideal state of self', with the latter
standing for a symbiotic fusion with the 'all good' symbiotic

mother, who was at one time part of the self in a blissful state
of well-being. (Mahler, 1972a, p. 333)

Separation-individuation is a life-long process, and further changes
can and do occur at other critical periods in an individual's life. In
many instances, particularly as twins go through late adolescence or
early adulthood, when separation experiences are to be dealt with, twins
are largely unprepared. In a study involving a fraternal male twin, the

subject himself made these remarks when discussing his twin:

12

I had not imagined life without him and, when the thought
occasionally passed through my mind, I had no fear for I did
not appreciate how much he meant to me . . . . But when he
left for college, I was emotionally shattered. (Karpman,
1953, p. 258)

Twins do relate to each other in a manner differing in certain
respects from other interpersonal relationships. Twin-like relation-
ships exist more frequently than is usually realized, a prime example
being a marriage in which the partners are mutually and exclusively
dependent on each other (Leonard, 1961). One even occasionally sees
married couples who dress alike, or twins who presumably marry other
twins to preserve the dual unity that they once had with their twin.
While certain aspects of the intertwin dependency may recede into the
background as twins mature, there is no doubt that other aspects of the

relationship persist into adulthood and influence later development.

Types and Frequency of Twins

 

For the past 50 years, the dominant View has been that there
are two twin-types. The first, identical, is the result of a very early
split, less than two weeks after conception, in a cell mass that would
normally have developed into one individual. (Fission occurring after
about 14 days is believed to result in conjoined twins.) Twins
occasioned by early fission have identical genes and, hence, are called
identical, monozygotic, or uniovular twins. While these twins have
identical heredity factors, such twins need not look alike, nor must
their personalities be the same, as both prenatal and postnatal factors
can account for tremendous differences. No two persons are exactly

alike, including identical twins.

13

The other type, fraternal, is the result of near simultaneous
fertilization of two ova by two sperm. These twins may look alike,
but they will be as much alike, or as unlike, as any sisters or
brothers. They are called fraternal, dizygotic, or binovular twins.

Recently, some scientists have postulated that a third type of
twin--identica1 in maternal contribution but diverse in paternal--
is possible. This third type of twin has been hypothesized to occur
as a result of one of two phenomena. In the first instance, the sperm
may cause the ovum to divide as fertilization occurs, providing
another ovum which, if fertilized by a second sperm, would result in
the development of twins who are neither identical nor fraternal
(Joseph, 1961; Koch, 1966). In the second instance, there may be a
second fertilization which occurs at least a month after the first,
and this phenomenon may account for any marked differences in the
maturity or size of twins at birth (Koch, 1966). The latter case may
also account for twins who are of different races, and for those who
are born some days apart (Hagedorn & Kizziar, 1974).

In order to determine twin type, physical characteristics of a
set: of twins are examined for similarity and dissimilarity.
Naturally, differences in sex, eye pigmentation, or blood group mean
that the twins are fraternal, but similarity in traits is not con-
clusive evidence that the twins are identical. A positive, although
impractical, test to determine twin type is the skin graft; the skin
will grow on the other twin if the two are identical, but will be
rejected if they are fraternal (Hagedorn & Kizziar, 1974).

About 12 in ITEM) births is a birth of twins. On the basis of

race, the highest rate of fraternal twinning is among Blacks

14
(14/1000 births), the next highest is among Caucasians (9/1000 births),
and the lowest is among Orientals and American Indians (6/1000 births).
While the rate of fraternal twinning varies from race to race, the
rate of identical twin births is constant for all races at about 4 per
1000 births. Identical twins represent about 30% of the total twin
population; fraternal same—sex and fraternal opposite-sex twins each
represent about 35% of the remainder of the twin population

(Glenn, 1966).

Research Questions

 

As the research illustrates, twins have a dual task: separating
from their mother, and separating from their twin. In this study,
the following research questions are posed.

1. Because of environmental influences, parental preferences,
and the attachments and conflicts in the twin relationship, do twins
exhibit less complete separation and individuation than non-twins?

2. Are there differences in the degree of separation and
individuation exhibited between identical and fraternal twins?

3. Are there differences in the degree of separation and
individuation exhibited between fraternal same—sex and fraternal

opposite-sex twins?

Overview
In this chapter, a brief theoretical description of the
separation—individuation process for both twins and non—twins has been
described. In chapter two, the literature concerning parental reac-
tions to twins, the intertwin relationship, and differences between

both twins and non-twins are reviewed. The design and methodology of

15

the study follows in chapter three. Chapter four includes the
presentation of the results of the study, and chapter five contains the
summary and conclusions.

In the next chapter, the pertinent literature concerning twins and

their relationship is reviewed in more detail.

CHAPTER 2

REVIEW OF THE LITERATURE

One reason for the persistent appearance of twins in the records
of man and his thought is the unexplained mystery surrounding their
special unity, regardless of whether it is based on love or hate, or
some combination of the two. Historically, themes in literature con-
cerning intertwin relationships, for example in the Old Testament or
Greek and Roman mythology, center around competition and rivalry, or
inseparability and the harmonious bond between twins. In the story
of the twins Jacob and Esau, the competition dates from the womb.

Each was determined to be the first-born; when Esau threatened to pre-
vail at the expense of his mother's life, Jacob gave way. Esau, the
favorite son of his father Isaac, was as the first-born to inherit his
father's goods and worldly possessions. However, Jacob, the favorite
of his mother Rebekah, bought his brother's birthright for some soup,
and then defrauded Isaac in order to receive the paternal blessing
that was meant for Esau.

Despite the fact that Greek traditions abound with stories of
sibling rivalry, twins are portrayed as exceptions to these rivalries
and jealousies. The theme of inseparability is perhaps most pronounced
in the story of the twins Castor and Pollux. In the last of their
battles while in search of the Golden Fleece, Castor was mortally

wounded; Pollux, being immortal, could not follow Castor to Hades, and

16

l7

wept with grief at the separation. Zeus, touched by Pollux's grief,
granted Castor the privilege of immortality, and the twins' insepara-
bility was consecrated by a fixed position among the stars, where they
became known as the Gemini or Dioscuri, the sons of the gods.

These themes are also prevalent in more current literature. For

example, in Wilder's (1927) The Bridge of San Luis Rey, a pair of

 

orphaned twins, Manuel and Estaban, whose identical appearance was the
cause of many jokes, vowed never to appear in public together. But
they felt an intense need for each other and worked together, remaining
silent and unapproachable to others. Manuel fell in love with an
actress, and as he became more involved with her, Estaban, seeing how
empty his life was, became listless and depressed. Despite this, he
encouraged Manuel to stay with the actress; Manuel, in turn, seeing all
the pain his brother was suffering, relinquished his attachment to the
actress. However, Manuel fell ill, and in his fevered delerium before
his death, accused Estaban of coming between him and his lover. Unable
to acknowledge his brother's death, Estaban assumed Manuel's identity,
and despondently wandered the streets. Finally, one day he tried to
kill himself. Surprised in the act by his employer, he cried out, "I
am alone, alone," realizing that he existed as almost nothing more than
a series of reactions to the union formed with his brother.

The modern psychological view of twinship combines elements of
Biblical, mythological, and popular conceptions, but places a particular
emphasis on differentiation and separation (Hartmann, 1934-35/1964;
Joseph & Tabor, 1961; Ortmeyer, 1970; Maenchen, 1968). Individual
psychological development within twin pairs is the result of a complex

interaction among three factors: innate constitutional factors;

18

parental attitudes, which can either enhance or diminish the importance
of these innate differences; and the relationship between the twins
themselves, which tends either toward equalization and similarity, or
differentiation and divergent development (Gifford, Murawski,
Braselton, & Young, 1966). The subtle interaction of these factors

can produce twins who are "as different as day and night," or, con-
versely, twins who are "like two peas in a pod."

Most twins seem to have some difficulty differentiating from each
other, and this can lead to difficulties which are not commonly found
in non-twins. However, there are a number of points which the reader
should bear in mind in the discussion which follows:

1. Not everything found in the personalities of twins can be
attributed to the twinship itself. As noted above, constitutional
factors make their contribution to personality formation, and not
everything that occurs in the twin relationship is the sole result of
being a twin (Hartmann, 1934-35/1964; Joseph, 1975; Orr, 1941).

2. Even though twins are born simultaneously, they are not sub-
ject to identical environments (Hartmann, 1934-35/1964; Kent, 1949).
Just as the environment is never the same for any two children in a
family, it is not the same for twins.

3. Even though twins may be identical, because of the second
point, it does not follow that the development, character, or behavior
of both members will be identical (Gifford, et al., 1966; Joseph, 1975;
Peto, 1946; Spitz, 1966; Zazzo, 1978). In fact, there seems to be a
surprising diversity in the personalities of identical twins, just as

there is between two siblings in the same family.

l9

4. Even though fraternal twins are no more alike, genetically,
than any brother or sister in the same family, they are often given a
special kind of treatment, and pressure may be unwittingly exerted to
make them behave as people feel twins should (Leonard, 1961). In
many instances, especially with fraternal same-sex twins, they are
dressed alike, given identical toys, and dealt with in ways which
accentuate their twinship (Orr, 1941). Each may suppress some of his/
her own distinct personality traits in an effort to fit into the
cultural stereotype that twins should be quite similar.

5. While no one single characteristic of a twin relationship is
different from that which may be found in a non-twin relationship,
"the sum adds up to a Gestalt by which it can be distinguished"

' or a cluster of

(Winestine, 1969, p. 442). A "twinning reaction,'
reactions with an intensity among those who happen to be twins,
includes such phenomena as hampering of independent activity, identi-
fication between the partners, feelings of lack of completeness,
conflict between the desire to differentiate and the need for each
other, and reciprocal relationships, in which one twin is dominant
and the other submissive (Joseph & Tabor, 1961, Ortmeyer, 1970;
Winestine, 1969).

Thus, there are factors, influenced by cultural and parental
attitudes, which encourage closeness and those which encourage distance.
In addition, the intertwin relationship itself is an important determi-

nant in separation-individuation. In the next section, general

cultural and parental attitudes and expectations will be examined.

20

Parental Reactions to Twins

 

The emotional reactions of parents who are about to give birth to
twins can range from shock to dismay to exhilaration. Some mothers
react to twins as a narcissistic pleasure, while others consider them a
narcissistic injury, although this occurs infrequently in Western
culture (Burlingham, 1952; Plank, 1958). Generally, the mother feels
that " . . . she has achieved something unusual and her twins . .
become precious possessions which other people are interested in,
wonder at, and even envy" (Burlingham, 1952, p. 12). These attitudes,
which are a reflection of cultural attitudes which emphasize the
positive aspects of twins, are somewhat unrealistic, as they neglect
to take into consideration the problems of handling two small infants
simultaneously, and the economic factors of feeding, clothing, and
caring for twins (Leonard, 1961). While negative feelings concerning
twins are rarely expressed by parents, some of the principal diffi-
culties in raising twins include exhaustion, especially during the
first six months; difficulties on the part of the parents in accepting
differences between the twins; uneasiness if one twin chooses one
parent as his/her favorite; and the "ganging up" of the twins against
the parents (Plank, 1958). Nonetheless, the parents will probably feel
privileged and proud, and many mothers join Mothers of Twins Clubs,
reinforcing pride in their social status (Leonard, 1961).

Many parents have a strong desire to emphasize the twin relation-
ship. For example, a mother who hears remarks about a dissimilarity
in her identical twins may behave as if a disparaging remark had been
made about them, and respond by pointing out their likeness

(Burlingham, 1952). Parents, especially of fraternal twins, may feel

21

disappointed if their twins grow up to be very dissimilar and no one
takes them for twins anymore (Scheinfeld, 1967). The narcissistic
pleasure derived from being the parents of twins may prompt the
parents to give the twins similar names, to give them similar hair
styles, to dress them alike, to give them identical toys, and in
general to try to keep them together. Scheinfeld (1967), in an
informal survey, reports that female twins are more frequently given
twin-type names (56% of those surveyed) than are male pairs (33% of
those surveyed) or male-female pairs (33% of those surveyed). In the
same survey, he found that many parents of same-sex twins dressed them
alike (83% for female twins and 73% for male twins), and planned to
continue to do so until the twins objected. A mother of identical
twin girls aged 4% is quoted by Scheinfeld: "We dressed them alike
until two and a half. It's no point in having cute twin girls without
making a big deal of it" (p. 14). And another mother of fraternal
twins said, "Dressing them alike is the only way to show they're twins"
(p. 14). Thus, many immature parents' ego needs are so bound up in
their twins that they consciously or subconsciously encourage either
dependency or similarity because of the attention that they as parents
receive (Hagedorn & Kizziar, 1974).

According to Winestine (1969), twins who insist, at later ages,
on identical attire illustrate a strong residual interidentification,
probably initially fostered by the mother, but with the locus of con-
trol now shifted from mother to child. The identical clothes may serve
as an exhibitionistic investment in the twinship for both parents and
the twins; dressing alike can add to the feeling of being special

(Koch, 1966), or the twins may fear not being noticed were they to

22

dress differently from their twin (Winestine, 1969). However, there
are some twins who resent dressing alike and being treated as a unit;
these twins as adults equate their mother to "stage mothers" who
pushed them into the limelight to satisfy their own ego needs
(Hagedorn & Kizziar, 1974).

Through parental responses, the twinship of both identical and
fraternal twins may be accentuated, and efforts on the part of the
twins to become distinct entities can be impeded by the parents.
Parents may experience difficulties because of the necessity of having
to adopt, at the same time, two modes of interaction with two children
at the same age, but with different characteristics. As a result,
some may stress the differences between the twins to facilitate inter-
action, while others attempt to resolve problems by treating the two
children as one (Neubauer, 1972; Shields, 1954). One of the main
findings in a study by Kent (1949) on maladjusted twins is that most
of the mothers of these twins want them to be alike, regardless of
whether they are identical or fraternal twins. For several of the
mothers, that the children did not develop completely alike presented
a special problem, and the mothers themselves seemed to view each
child as one half of a whole. The parental inability to acknowledge
a separate identity for each of the twins is sometimes carried to an
extreme, as can be seen in this 22-year-old female identical twin:

My sister had to wear a brace to correct a bone defect. I was

forced to wear the brace although I was fine. Now I feel

angry about it, but then I just accepted it. To the present

day my father is confused as to which is which." (Ortmeyer,
1970, p. 131)

23

If the parents do not perceive and encourage the twins' uniqueness,
unit identity may be strengthened, and personal identity weakened
(Hagedorn & Kizziar, 1974).

It is essential that the parents be able to distinguish one twin
from the other in order to love and treat each twin as an individual.
The necessary one-to-one relationship seems to be dependent on distinct
delineation between the twins, and the possibility of being alone with
each twin, at least for short periods of time (Leonard, 1961). The
parents have to cope with similarity or dissimilarity, sameness or
individuation, and their attitude is decisive. Gifford et a1. (1966)
report, in their four-year longitudinal study on a pair of identical
twins, that if parents emphasize opportunities for the individual and
separate development of each twin, and minimize dependency between the
twins, two distinct and permanent personality patterns can and will
emerge. Similar findings are reported by Allen, Greenspan, and Pollin
(1976), in a two-year longitudinal study of 10 pairs of twins, eight
identical and two fraternal. When differences between the twins were
perceived by the parents, as they were in most instances, parents
related to each twin in a different manner. They delineated a separate
role for each twin, and then in turn subtly encouraged or reinforced
conformity with the selected role.

In an effort to establish an individual identity in each twin,
the "separate but equal" approach is sometimes adopted. However,
because of parental identification with certain characteristics of each
twin, it is not uncommon for this approach to develop into "separate
and unequal." A unique study on the effect of parental perceptions

on early development is the previously mentioned work conducted by

24

Allen et a1. (1976). Even though most of the twins were identical and
in many ways remarkably similar, the parents "often discerned the
smallest differences and either exaggerated them or attached special
significance to them" (p. 66). It was the rule, rather than the
exception, for one parent to focus on the positive aspects of the twin
with which he/she identified, and the negative aspects of the other
twin.

For example, A was described by the father as being stronger,

more aggressive, and more daring. The mother was quick to

point to a deficiency in A——name1y, that he was more distant

with strangers, whereas B was more social, 'a charmer, he will
smile, and he will come to a stranger first.' (p. 69)

Certain early characteristics of each twin exert an influence on the
parent and lead to identification with one twin and to what at times
could be appropriately termed indifference toward, or overt rejection
of, the other twin. Although Shields (1954), in a study of 62 pairs
of same-sex twins, found instances of overt parental preferences to be
quite rare, he did report that parents of fraternal twins were most
insistent that they made no difference between the twins, that they
tried to give them the same of everything. He compared these parents
to parents of identical twins, and concluded, "To risk a paradoxical
generalization, the parents of identical twins make a special effort
to treat their twins differently, those of fraternal twins to treat
them the same" (p. 230).

Many authors have commented on the high frequency of "splitting"
of the twins between the mother and the father (Abraham, 1953;
Benjamin, unpublished, cited by Gifford et al., 1966; Demarest &
Winestine, 1955; Hagedorn & Kizziar, 1974; Karpman, 1953; Mesnikoff,

Rainer, Kolb, & Carr, 1963; von Bracken, 1934). In her study on

25

maladjusted twins, Kent (1949) reported that most mothers showed a
definite preference for one twin, or found it more difficult to deal
with one twin. Plank (1958) and Burlingham (1952) both cited instances
in which one twin would claim or appropriate the mother, and the other
the father, leading to the conclusion that this "splitting" is probably
a mutual process between parent and child.

Thus, the parents, either consciously or unconsciously, react to
each twin in a different manner, and preferences are established.
These preferences seem to be more marked in fraternal than in identical
twins, and are especially noticeable in opposite-sex twins (Hagedorn &
Kizziar, 1974; Karpman, 1953; Kent, 1949; Scheinfeld, 1967). Develop-
mental differences in boy-girl pairs may encourage these parental
preferences, or they may be the result of the parents' own relation-
ships with, or perceptions of, the two sexes (Hagedorn & Kizziar, 1974).
Burlingham (1952) noted that these parental preferences can alternate;
at one stage a parent may prefer one twin, and at a later stage, the
other twin.

These preferences are significant, for when one twin is preferred
by one parent, the other twin may attempt to compensate for the loss
of that parent by identifying with other members of the family, par-
ticularly the twin (Demarest & Winestine, 1955; Holden, 1965;
Joseph & Tabor, 1961; Karpman, 1953; Lidz, Schafer, Fleck, Cornelison,
& Terry, 1962). This is perhaps best illustrated by Holden's (1965)
report of his analysis of a pair of 27-year-old identical male twins.
In Holden's words, each twin was "shackled to the other in a pathologi-
cal clincH'(p. 859). Initially, neither twin would acknowledge that

any differences existed between them; they insisted that they not be

26

seen separately because they were one person. After many sessions,

one of the twins, Adrian, stated that he knew that he was his mother's
favorite, and the other twin, Richard, responded that he was aware of
this, and felt that he had to internalize Adrian in order to maintain
a link with their mother. This had been carried to such great lengths
that any individual pursuit or interest was seen as a threat to their
bond with their mother. Thus, when parental preferences for one or
another twin are established and quite marked, there can be a ceding of
one parent to one twin, and a ceding of the other parent to the other
twin, with ties to the ceded parent maintained through the twin. Inter-
twin identification can be further emphasized and strengthened, lead-
ing to a decrease in individual identity.

In summary, in this culture, the positive factors involved in
giving birth to twins seem to override the negative factors, and many
parents seem to derive great pleasure from the experience. This can
lead to a desire on the part of the parents to emphasize and accentuate
the twin relationship, thereby hindering the development of a separate
identity for each twin. In some instances, parental preferences for
one twin over the other occur, and the "rejected" twin may compensate
for the loss of one parent by identifying with other family members,
including the twin. This too can contribute to intertwin identifica-
tion, helping to further the unit identity at the cost of an indi-
vidual identity. The relationship between the twins themselves, and
its contribution to the unit identity which may develop will be dis-

cussed in the next section.

27

The Intertwin Relationship

 

As previously stated, the majority of the material concerning the
intertwin relationship is based on individual case histories from
psychoanalytic or psychotherapeutic researchers. There are very few
studies which involve comparisons of twins to non-twins, or comparisons
between the different twin-types. For this reason, the intertwin rela-
tionship will first be discussed as it has been outlined on the basis
of case studies, and subsequently the studies that have involved groups
of twins will be reviewed. The common findings between the two will

then be explored.

Intertwin Identification

 

In the discussion of the separation-individuation process in
twins, it was seen that just as there is an initial state of symbiosis,
or oneness, with the mother, there is also an initial state of
symbiosis with the twin. Each twin gradually progresses from this
undifferentiated stage to an awareness of some degree of separateness
(both from the mother and the twin), but the presence of the twin can
interfere with and inhibit the separation-individuation process
(Ackerman, 1975; Winestine, 1969). The profound and complicating
influence of the twin has been stressed by Leonard:

It is of utmost importance in understanding later development

to realize that the one human being who is most constant

within the twin infant's range of perception is not his mother
but his twin. (1961, p. 304)

From about the fifth or sixth month, twins are aware enough of
each other to have a quieting effect on each other. Just as the mere
presence of a mother in a room can soothe a disturbed infant, the

presence of the twin gives the other a sense of not being alone

28

(Leonard, 1961). Parents, preoccupied with household and career
responsibilities, may notice this mutual effect that the twins have on
each other, and will leave them together to play and entertain each
other as long as they appear to be content. The twins may often be
left in each other's company, and there is an increasing influence of
the mood of one upon the other. Because of the lack of adequate ego
boundaries at a young age, each may have difficulty distinguishing
his/her own thoughts, behaviors, and wishes from those of the other
twin. There is a general confusion on the part of the twins as to
where the boundaries between themselves and their twin begin and end.
Thus, the developing ego responds to the needs and drives of the other
twin, as well as to those within the self (Lidz et al., 1962).

This situation limits the necessary parent-child interaction and
identification, which are prerequisites for normal separation and
individuation. To the detriment of the twins, parent-child contact is
insufficient, and twin-twin contact, which is characterized by inter-
action with an individual in the same developmental phase, is excessive.
Given less opportunity to interact with the mother, the twins resort
to imitation and identification with the nearest individual, their
twin (Winestine, 1969).

That this twin-twin contact has a negative developmental impact is
evident in the study of Burlingham (1952). She reports that one pair
of identical twins (Bert and Bill), imitated each other's movements and
gestures from 12 months of age. While both of them were constantly
trying to find new ways of entertaining each other, such copying games

hindered normal development.

29

It was felt that, if the twins had been brought up without
each other, Bert would have been able to develop normally.

The influence that Bill exerted on him made it impossible for
him to allow his ego to develop as it would have done if he had
not been carried away by Bill's dominant, domineering, and
erratic nature. Bill, if brought up without his twin, would
not have had the added thrill of observing the reactions he
created in Bert and would have lacked the enjoyment of watch-
ing Bert, which obviously gave him sensations of excitement.
The double pleasure created in this way absorbed them and pre-
vented them from achieving the development normal for their

age. (p. 26)

In addition to retarded development, the twin relationship can
foster the development of unique communication patterns between twins.
With imitation of sounds and gestures between the twins, it is not
uncommon for them to develop their own secret language-~idiolalia--
which others, including the parents, cannot understand (Hagedorn &
Kizziar, 1974; Holden, 1975; Maenchen, 1968; Scheinfeld, 1967; Zazzo,
1978). (Leonard terms this secret language "echolalia," while Zazzo
uses the term "cryptophasia" in order to stress its incommunicability
to others.) These communication patterns can serve to isolate the
twins from outside attachments, and in some instances are used by the
twins to emphasize their unity.

A separate existence for either twin was seen as quite

impossible, indeed they were explicit that they would rather

die than separate. The existence of their secret language

was shown to me as proof of their unity, and I was repeatedly

reassured that every thought they had was shared, that they
had no secrets from each other, etc. (Holden, 1965, p. 864)

Another aspect of the indirect effects of the twin relationship
that has been studied is identity confusion (Lezine, 1951). In a test
at 24 months in which children were supposed to say their own name,
only 40% of the twins passed, as compared to 60% of the non-twins.

At the same age level, the children were supposed to be able to point

to parts of their own body and to identify them in a picture. Again,

30

42% of the twins passed, as compared to 60% of the non-twins. In
addition, one twin came when the other's name was called, or would
point to the parts of the body on the body of the twin instead of on
him-/herself. These tests showed the difficulty that twins have in
separating self from non-self, and the confusion of identity appears
to be one of the results of intertwin identification (Leonard, 1961).
Burlingham (1952) also makes reference to the inability of twins to
see themselves as separate identities. For example, one set of twins
used to take turns crying whenever the mother left home; when queried
as to why both did not cry, the one who was not crying said, "Sister's
crying, I don't need to."

Thus, it seems that the presence of another individual, in close
emotional and physical proximity, and in the same developmental phase,
does have a definite effect. This effect is perhaps quite strong
because close contact occurs before ego boundaries are firmly
established, and as Glenn (1966) notes, uncertainty about ego boundaries
makes for excessive employment of identification. Being a member of a
twin pair, either fraternal or identical, encourages the phenomenon of
the "twinning reaction," which consists of mutual interidentification
and part fusion of the self-representation and object representation of
the other member of the pair (Joseph & Tabor, 1961). This leads to
diffuseness of ego boundaries between the twins.

By and large, there is a mutual interdependency and failure to

completely differentiate one's self from the twin, so that a

complete self-representation is not found. Study of the

protocols of the various case reports shows that this state of
affairs exists to varying degrees in all of these patients.

While mindful of Hartmann's admonition that not everything that

is found in the personality of a twin should be ascribed to the

twinship itself, where such a finding is so universally reported

in all studies, it seems significant. (Joseph & Tabor, 1961,
p. 276)

31
The twinning reaction is based on multiple factors, including (a) the
occurrence of relatively simultaneous passage through the progressive
phases of maturation and development; (b) the influence of the environ-
ment toward nondifferentiation; (c) the physical similarities between
twins; (d) the mutual choice of the twin as an object of libidinal
and narcissistic gratification; and (e) the inhibition of or defense
against hostile impulses directed at the twin. The first two factors
have been discussed previously, while the remaining three require
further elaboration.

The importance of physical similarities between the twins is
crucial. The intensity with which twins identify with each other
seems to be strongly related to the degree of resemblance, which is
not necessarily correlated with twin type (Leonard, 1961). For example,
some identical twins differ more in weight at birth, and therefore in
appearance, than do some fraternal twins. The more alike twins are,
the stronger the tendency on the part of the environment to treat them
as a unit, which emphasizes their identification with each other and
tends to make them feel as though they belong together. Furthermore,
physical similarity exerts an early influence at a time when separa-
tion of self and non-self occurs, and continued confrontation with a
mirror image inhibits this separation of self from non-self, thus pro-
moting the fusion of self and object representations (Joseph & Tabor,
1961). For example, Leonard (1961) reports these observations on a
young set of twins.

. Approximately in the seventh month, these . . . twins

were seated on the bed opposite each other and were playing

with each other in the manner that a single child might play

with a mirror held up to him, namely, reaching out and

touching. However, this particular situation had other
elements in it; each baby seemed to be exploring the body of

32
the other in a way that, if left to himself, one baby explores

his own body. Fingers were poked into the navel of the other,
toward the eyes and into the mouth. (p. 308)

Thus, a twin may initially perceive his/her twin as being a mirror
image, and conversely, Burlingham (1952) reports instances in which the
true mirror image was perceived not as the self but as the twin. While
it would seem that, with time, basic similarities in appearance and
behavior would be gradually overlaid by acquired differences, the
identification of the twins with each other can minimize the develop-
ment of such differences. In fact, through excessive identification
with the twin, twins can become more alike as they mature (Burlingham,
1952).

Accompanying the intertwin identification is a strong tie between
the twins based on the mutual stimulation that they provide for each
other. It was previously noted that because of the monumental task of
handling two infants at the same time, twins are rarely the sole
recipient of the parents' attention, and must generally share such
attention with their twin. There may be inadequate individual contact,
both emotional and physical, and the twins may turn to each other not
only for mutual entertainment, but for consolation and attention as
well (Terry, 1975). The fact that twins must share parental attention
and time can lead to periods of quite intense frustration. Conversely,
turning to each other for consolation and attention can lead to periods
of too intense gratification as well (Glenn, 1966).

An example of the frustration that twins experience can be seen in
the feEding situation. As Leonard (1961) noted, it is a rare set of
twins who conveniently fit their demands into a schedule in which the

mother can feed one twin while the other sleeps. ”All too frequently

33

and frustratingly, the feeding of one is accompanied by the scream-
int protest of the other infant" (p. 304). While the behavior of a
pair of twins is not usually identical, e.g., one may be indifferent
as the other is fed, or one twin may object months before the other,
the first competition for attention seems to center around feeding

(Burlingham, 1952). Burlingham vividly illustrates the feeding of a

pair of identical twins, Jessie and Bessie.

At 13 months the mother would sit them at a table opposite each
other, and she would then take her place between them. The
mother had to feed Bessie twice as quickly, because each time

she picked up the spoon to feed Jessie, Bessie would start

screaming. Jessie was forced to wait while the mother tried to

satisfy Bessie by pushing two spoonfuls into her mouth for

every one she gave Jessie. (1952, p. 21)

While one twin is fed, the other usually waits; while one is diapered,
the other waits; while one is bathed, the other waits. This can result
in the build-up of tension that is not released for long periods of
time, and this frustration may be one of the sources of the rage toward
both the mother and the other twin, which is prominent in twins

(Glenn, 1966).

The mutual gratification between the twins results from the twins'
use of each other as sources of entertainment, attention, and consola-
tion. One twin will not infrequently use the other as a parental sub-
stitute if he/she is disappointed in the parent, or if the parent is
absent for a period of time. All children are at times disappointed or
frustrated with their parents, but twins have the opportunity to turn
to each other as a source of gratification should discomfort arise

(Joseph & Tabor, 1961). The substitution of each other for the parent

was noted by Burlingham (1952) in all three twin pairs in her study.

34

Whenever they are disappointed in their parents, they turn to
each other for consolation and understanding. They substitute
each other for the mother or other loved person when they find
them lacking-dmothering, comforting, helping, protecting, and
loving each other. (p. 81)

As Jessie and Bessie were discussing an impending separation from
their mother, Bessie comforted herself with the words, "We are never
alone. I always have Jessie to talk to." Jessie laughed, and said,
"I always have Bessie, so we aren't lonely" (Burlingham, 1952, p. 87).
Twins soon learn that they can fall back on, or gratify, each other,
in cases of parental disappointment or absence.

However, this use of each other as sources of gratification can
lead to an inhibition of the individuation process, for as Jacobson
(1954) pointed out, excessive gratification or deprivation can lead
to confusion of self and object representations. The twins' self-
images become blurred or blend in with that of their twin. For
example, Spitz's (1962) analysis of Harlow's monkey experiments reveals
too much reciprocity between same-age monkeys raised on a cloth
mother, in contrast to those raised by a real mother. The identical
needs of those monkeys with surrogate mothers were completely and
reciprocally fulfilled, resulting in a closed and static system which
was not amenable to any outside influence. They clung to each other,
were unable to form any other relationships, and did not engage in play
with other monkeys. Spitz concluded that these monkeys were arrested
on what in man would be called the primary narcissistic level. The
"together-together" monkey relationship entailed no frustration and,
hence, "neither incentive nor push to form different relations"

(p. 295).

35

In the mother-child system, the needs of the child and the needs
of the mother are, though in certain respects complementary, quite
dissimilar. The mother will not offer simple and constant gratifica-
tion, but "a wealth of action shifting from approach to retreat, from
embracing to rejecting, from gratification to frustration" (p. 293),
thus providing the infant with a variety of experiences, and forcing a
variety of responses. These circular social interactions promote the
separation-individuation process, and the encouragement of relations
with others.

Each of her responses represents a push in the direction of

developmental unfolding of the infant's personality-~each of

them bringing him nearer to autonomy from the mother and to

seeking contact not only with the "other" but also with the
"generalized other." (Spitz, 1962, p. 294)

This pattern is not true of the "together-together" relationship
in which demands and needs are mutually gratified with few frustrations.
With twins, the mutual stimulation and lack of frustration can inter-
fere with the development of object relations and with the evolution
of normal personality (Maenchen, 1968). Instead of the necessary
identification with a competent adult and mutuality of imitation
between mother and child, there is an identification with an equally
helpless twin. Ackerman's (1975) description of a 28-year-old female
identical twin provides an illustration of the relationship that can
develop as a result of the intertwin identification.

In many ways her twinship impaired separation and individua-

tion by providing a continuous, mirroring, narcissistic object

with which to identify herself, to rely on and to love . . .

Tension-alleviating functions were a mutual process of sooth-

ing the other and the self. Moreover, the twin served as a
transitional object that was not given up. (pp. 396-397)

36

It seems, then, that there is a certain amount of frustration and
gratification inherent in the twin relationship, with perhaps too much
frustration in the parent-child interactions, and too much gratifica-
tion in the twin-twin interactions. The resulting effect on the
separation-individuation process is detrimental in that a primary
object relationship is established with a person who is not different
but the same, and with whom most experiences are shared (Lidz et al.,
1962). The persistence of the twin as a need-satisfying, mirroring,
idealized object retards individuation.

The capacity for deep and satisfying object relationships would

depend on both a gratifying, constant, responsive period of

symbiosis with mother, as well as gradual, safe phases of

separation and frustration. Trust, confidence and mastery

reflect dependable identifications. If a need-satisfying and

tension-alleviating object fulfills its role too well, or

anachronistically persists, delaying the ontogenetic timetable

of individuation, then libidinal fixation and narcissistic
striving may occur. (Ackerman, 1975, p. 407)

Rivalry and Ambivalence

 

However, just as there is a tie between the twins based on need
which inhibits separation-individuation, there is a pull in another
direction, based on rivalry and competition, which encourages
separation-individuation (Joseph, 1961). This rivalry and competition
probably precedes the awareness on the part of the twins of their
special relationship; the first experience with the twin is clearly
that of a rival and intruder in the earliest phase of instinctual
gratification.

In the initial phase there is the self-centered wish to

possess the breast and the mother without regard for the

sibling. This is coupled with resentment toward both mother

and sibling for having to share food, attention, or love in
any form. (Arlow, 1960, p. 194)

37

Within a short period of time, however, comes the realization that
exclusive possession in any sense is impossible; some form of renuncia-
tion of exclusivity is inevitable, and sharing will have to occur. Out
of this realization of the necessity for sharing, one twin begins to be
willing to renounce some of his/her demands on the condition that an
equal renunciation can be exacted from the rival, the other twin. In
this manner, a truce is effected in which the feelings of competition,
hostility, and jealousy are transformed into a resolution to share
things equally. But this resolution to share equally is a mere continua-
tion of their former competitive relationship.

The struggle is now centered around the desire to have, not

more, not less, but the same. To have the same prevents the other

from having more and in this way they are able to strike a
balance. (Burlingham, 1952, pp. 62-63)

This is a very tenuous balance and the rivalry is by no means
eliminated by this solution. As Arlow (1960) notes, any transgression
on the part of one twin can precipitate an immediate and violent
retaliation. For example, if one twin should be the recipient of a
gift that he/she is not willing to share with the other, the rivalry and
resentment will quickly resurface. Furthermore, this balance is not
necessarily limited to the possession of objects; the effort to strike
a balance can permeate every aspect of the twin relationship, as is
illustrated in Orr's analysis of a male fraternal twin.

Two sides of the twin rivalry thus became apparent; if the

twin excelled and was preferred, the patient felt rejected and

became hostile towards the twin as well as towards those who

showed this preference; but if the patient excelled, he felt
anxious lest his twin hate him with the same intensity he felt

in the reverse situation. This dilemma could be solved only

if neither excelled or was preferred; that is, if the patient

were as much like his twin as possible. A premium was thus
placed upon their being "identical." (1941, p. 291)

38

Orr goes on to state that such a twin relationship can be maintained
only by sacrificing individuality and development as a separate
personality.

The ambivalence created by this situation, in which the growing
need for each other acts as a check on the negative feelings which arise
from envy, jealousy, and competition, appears to be quite intense
among twins (Arlow, 1960; Glenn, 1966; Kent, 1949; Steinfeld,
unpublished, cited by Orr, 1941). As Joseph & Tabor (1961) point out,
the twin relationship is fraught with many conflicting affects. There
are feelings of rivalry, hostility and jealousy, deriving from attention
given to the other twin, guilt over these feelings, and attempts to
deny the guilt associated with such feelings. There may be feelings of
inferiority, deriving from either developmental differences or from the
invidious comparisons of parents and outsiders. At the same time,
there is a real love between the twins, and the realization that the
twin is needed, both as an ally and as a source of gratification. Based
partly on a need for each other, and partly as a defense against hostile
impulses toward each other, mutual interidentification can serve a
defensive role in permitting a state of coexistence in which neither
gains an advantage over the other, and ties between them are
strengthened (Joseph & Tabor, 1961). In a sense, notes Arlow (1960),
it is probable that most twins purchase good relations with each other
at the expense of their relationships with other individuals.

Because of intertwin identification, reaction formation, and in
particular, parental admonitions about expressing hostility, overt
expressions of hostility directed at the twin appear to be rare.

Hagedorn & Kizziar (1974) note the irony of this situation: the more

39

closely two people are associated, the more likely they are to come into
conflict, but even though no two people appear to be more closely
associated than are twins, aggression against one's twin is likely to be
unacceptable.

From the point of view of the parents, the insistent clamoring

for attention on the part of each twin can be unbearably harrow-

ing. Not realizing how important it is that twins fight it out

and learn to accept each other as different individuals, parents

frequently do everything in their power to try to make the

twins conform to the culturally accepted picture of what the
twin relationship should be like. (Leonard, 1961, p. 315)

The final attitude which the twins adopt can depend on which
aspect of the ambivalent relationship is repressed (Arlow, 1960). In
some twins the competition is maintained as a primary characteristic
of the relationship; they may try to "out-do, out-perform, out-wit, and
out-maneuver their twin-—to come out on top in their parents' and
others' eyes no matter what the cost" (Hagedorn & Kizziar, 1974,

p. 117). In other instances, the rivalry may result not in open
hostility but in cold war (Maenchen, 1968). For some, the solution is
to attempt to maintain conformity and equality, as in a case cited by
Winestine (1969) in which if the mother of a pair of twins failed to pro-
vide two clean pairs of socks of matching color, they divided the socks
between them, i.e., each wore a blue and a brown sock. Others may seek
a resolution through accentuating the differences between them so that
a more or less complementary relationship exists between them. In this
manner, a "division of labor" is effected. One twin may, for example,
handle social interactions, taking responsibility for dealing with the
outside world (the "Minister of Foreign Affairs"), while the other may

deal with the twins' private life, making decisions or acting as the

‘

4O
conscience of the pair (the "Minister of the Interior") (von Bracken,
1934; Shields, 1954; Zazzo, 1978).

Thus, ambivalence, based on the need for the twin as a source of
gratification and the realization that he/she is also a contender for
affection and attention, seems to be highly characteristic of the twin
relationship. Twins have an acute rivalry to cope with; it seems to be
more severe than ordinary sibling rivalry, and starts at an earlier age
than it does with siblings. It can be dealt with through excessive
competition, maintenance of conformity, or division of roles between

the twins.

Complementary Relationships

 

The division of roles can lead to an increased emphasis of a
phenomenon which is frequently observable in twins, namely a dominant-
submissive, or active-passive, pattern. The first signs of such a
pattern in twins may appear quite early in development, as early as
eight months of age, according to Burlingham (1952), and in some
instances are quite marked.

Such differences--sometimes subtle but frequently vivid--
include: (1) a clear-cut difference in the relative ease of
adaptation to new stimuli, including a difference in initial
fearfulness (dependence-independence); (2) a tendency for one
twin to be relatively more methodical and thoughtful, the

other more excitable and emotional; (3) a difference in object
orientation, one twin appearing to be relatively more interested
in people (social) and the other more oriented toward inanimate
objects; (4) a difference in approach to the environment, one
twin tending to explore patiently and thoroughly, the other
more actively searching for some new stimulus; (5) a tendency
for one twin to be more passive, the other more confident and
assertive. (Allen et al., 1976, p. 66)

As a specific example of differences in behavior, the stronger twin may

bite, push, pull, or snatch things away from the weaker twin, who will

41

in no way try to defend him/herself, but behaves in a completely
passive manner.

Dominant-submissive roles may switch back and forth between the
twins, i.e., if the stronger twin should get sick, the other twin will
take advantage of the situation (Burlingham, 1952; Neubauer, 1972;
Shields, 1954). However, most of the switching appears to occur when
the twins are younger; with time, the roles become more stabilized. In
general, it seems that a role is delineated for each twin, which is
subtly encouraged or reinforced by the parents, so that the child begins
to behave according to parental cues and expectations (Allen et al.,
1976; Kent, 1949). Through the interaction of constitutional factors,
the intertwin relationship, and parental responses, a dominant-
submissive pattern can be established. While the following example, con-
cerning five—year-old female fraternal twins, illustrates such a
relationship to a greater degree than is typical of most twin rela-
tionships, it nonetheless shows how such a relationship can be formed.

The mother complained of her inability to gain full satisfaction
from either child and, during their infancy, yearned to be with
one child at a time. Nevertheless, a strong preference for

Susan over Ann was early established because Susan was the first-
born and more wanted child. . . . The mother expressed preference
for the more dynamic and active personality of Susan in contrast
to Ann whom she thought the less interesting and more phlegmatic
. . . . She consistently permitted Susan to thwart Ann's early
attempts to seek contact with the mother; Susan shouted Ann down
when the latter attempted to talk with the mother; Susan could
not sleep unless the mother left Ann's bedside and the room,
until Ann finally stopped all her requests for the mother's
presence; Susan attacked the mother when Ann attempted to seek
solace from her at times when Susan had sat on Ann or had
forcibly taken something from Ann, until finally Ann also stopped
these overtures . . . . The mother felt that each twin had a
negative effect upon the other, thus creating a more difficult
task for her; Ann would have been less difficult to rear without
the stimulating effect of Susan; Susan displayed fears only by
"contagion" and exposure to Ann . . . . The mother summed up

42
their relationship by saying: "Ann serves as Susan's hands,

but Susan is like a drug for Ann and Ann cannot do without Susan."
(Demarest & Winestine, 1955, pp. 339-340)

In this case, not only was a clear dominant-submissive pattern
quite marked, but the dominant twin, Susan, was also unwilling to
relinquish her control over Ann. This phenomenon has been noted by
other researchers (Arlow, 1960; Holden, 1965; Potash & Brunell, 1974);
the dominant twin seems to be dependent on the submissive twin, and
vice versa, so that while each resents the other, each also relies on
the other. The dominant twin may feel that if he/she were to relinquish
control or surveillance over the other twin, the other would gain some
advantage (Arlow, 1960). Or the dominant twin may fear hurting his/her
more passive twin, perhaps alienating him or her, and thereby alienating
him-lherself in the process (Holden, 1965).

Such dominant-submissive patterns inhibit the separation-
individuation process for both partners; each feels a need for the other,
and cannot let the other be free and independent. While the dominant
twin may be perceived as being the more separate and individuated, this
is not necessarily the case. He/she may reveal brittle ego features
if threatened with the loss of domination over the twin, and the self
representation may include the incorporation of the twin through the act
of domination (Winestine, 1969). In contrast, the submissive twin may
welcome a release from the domination and become more accessible to
other relationships (Demarest & Winestine, 1955; Winestine, 1969), as
was the case with Ann, who responded to therapy in a more effective
manner than her twin, Susan.

In addition to the dominant-submissive pattern, other

"complementary" personality traits in twins may develop. For example,

43

it was previously noted that one twin may take the lead in social
interactions, while the other may take care of the relationship between
the twins themselves. While working together, coordination may be so
pronounced that the two figures of the twins seem fused into a single
four-handed figure (Cronin, 1933). In Karpman's words,

It would seem that there is often between twins a repulsion

and attraction, positive and negative, active and passive

complementary traits, so that they fit each other as the convex
fits the concave, making a whole (1953, p. 248).

Maenchen (1968) takes a stance which is somewhat contradictory to
Karpman's. In her analysis of a lZ-year-old identical male twin, she
found that while both twins "used each other in the same way, their
mutual attraction being both narcissistic enui genuinely affectionate,
they did not quite complement each other--they were two halves which
did not make a whole" (p. 441). Even though the twins were able to
function when they were together (although at a borderline level), when
they were apart there was a diminished capability in maintaining ego
boundaries. Overall, most researchers view the twinship in a light
which is more compatible with Maenchen's than Karpman's. While there
are feelings of union and strength, and an awareness of being an object
of special interest to others, twins may feel at somewhat of a loss
when not in the company of their twins. Cohesiveness of the self may
not be experienced as being separate, but as being joined to a kindred
spirit, a mirror image; with the twin there is a sense of omnipotence
and power, but without the twin, there is anxiety and a sense of loss
(Ackerman, 1975; Winestine, 1969).

According to Ortmeyer (1970), it is not that a trait is completely

present in one twin and absent in the other, but that a trait is more

44

fully developed and more structured in one twin than in the other.

Out of this differential development of traits, there arises a

"we-self" identity between the twins, and they appear to function as a

cohesive and efficient unit--until, that is, separation occurs.
Clinical knowledge of this twin seems to support the hypothesis
of the we-self. She was similar to her sister in physical
appearance, yet not in personality. She seemed neither identical
nor a mirror image of her sister but, rather, to have comple-
mentary personality attributes. Together with her sister, they
apparently functioned as a unit; the patient was accustomed to
having both personality attributes. Separately, she sorely
missed certain of her twin's personality attributes, not having
acquired them sufficiently in herself. Such personality traits
were not totally absent, but relatively undeveloped in her.
(Ortmeyer, 1970, p. 133)

Problems arise when, without the personality of his/her counterpart,

the twin faces the loss of traits necessary for his/her expected

personality functioning. Ortmeyer found that with the loss of the twin,

the other twin does not develop the deficit, but instead seeks out twin

substitutes who will conform to the relationship with the lost twin.

Separation from the Twin

 

Many twins, especially those who are reared as a unit and not
encouraged by their parents to develop individually, report feelings of
being half a person and incomplete without their twin (Hagedorn &
Kizziar, 1974). In a case reported by Knight (unpublished, cited by
Orr, 1941), for example, an identical male twin felt incomplete when
not with his twin, and never felt comfortable meeting new people until
his twin had also met them. Some of these same twins report that their
greatest fear is that their twin would die, that they could not con-
tinue on their own. This is how one twin described his first separation

from his twin when he left for college.

45
The power of the shock to my emotional system is eloquent
proof of the extent of my emotional reliance on him. I wrote
to him that it was as if a part of me had gone with him. I
realize now that he had become a vital part of my emotional life
and when he left a gaping hole remained . . . . My confidence,
my optimism, the pleasure of school, all disappeared as quick as

a flash and in their stead came hopelessness, fear, lack of confi-
dence, insecurity, misery. (Karpman, 1953, p. 258)

Burlingham (1952) had an opportunity to observe the reactions of twins
when they were separated at a young age, and found that indifference at
separation occurred at about 16 to 18 months of age. In addition,
separation from the twin had the same emotional value and produced the
same reaction as separation from the mother, i.e., the feelings of hurt
and anger at being separated from the love-object were expressed by
rejection of the loved person at the moment of reunion. At the same
time, the twins seemed to suffer acutely when separated from each
other, with the one who was left taking over the name, clothes, and
characteristics of the missing twin. Winestine (1969) also reports
that some of the twins she studied, aged 8 to 12 years, expressed a
desire never to be separated.
A expresses some wish to be Siamese twins as the only assurance
that he and his twin will never be separated. He also expresses
preference for the same class placement rather than the school's
policy of separating twins and indicates that he concentrates

better in the presence of his twin. Both imply that they feel
part of a whole. . . . They sleep together in a double bed, time

their routines concomitantly, intend never to marry, and to

live together as adults. (p. 453)

Perhaps it is the sense of loss when separated from the twin
which is responsible for the need, noticeable in some twins, to
"recreate" the twinship with others, including parents, children,
spouses, friends, and therapists (Ackerman, 1975; Glenn, 1966; Joseph,

1959; Steele, unpublished, cited by Joseph, 1961). In the analysis of

a fraternal opposite-sex male twin, for example, Glenn (1966) reports

46

that his client, who had an intensely competitive relationship with
his sister, entered the same occupation as his sister, and found a
business partner who would dress like him, eat the same food, and
purchase the same type of car. In the transference, the twin problem
was prominent, as the client had a strong desire to picture the analyst
as a twin. Steele (unpublished, cited by Joseph, 1961) speaks of

the analytic situation as a "situation par excellence for recreating a

 

'twin relationship'" (p. 162).

There are two people who share a common purpose, develop a
secret language in a common room, etc. Inevitably, therefore,
the patient's need to recreate the twin situation is fostered
by analysis. This results in a 'sticky' type of transference.
Problems of terminating the analysis are increased because

the twin fantasizes a perpetual analysis with his 'twin analyst.‘
(Joseph, 1961, p. 162)

However, no matter how strong the intertwin identification and
other ties which seem to keep twins together, separation and individua-
tion, to whatever extent, are inevitable (Lidz et al., 1962). In their
report concerning 37-year-old male identical twins, who were very close,
and even at times confused about which experiences had happened to which
twin, Joseph & Tabor (1961) found that two distinct personalities did

emerge.

Aside from the close physical proximity imposed upon them by
their environment, aside from the drive toward unity expressed
by the family, aside from their need for each other as a source
of the narcissistic gratification so often denied by the need-
satisfying objects, aside from the use of each other to live out
instinctual conflicts, and aside from the need to deny guilt at
hostile feelings toward each other by remaining a unity--they
still are different individuals. (p. 294)

It is also possible that the loss of individual identity may be
compensated for by the supportive aspects of such a bond (Leonard, 1961)

The reassurance and security gained may counteract whatever weakening

47
may be suffered by the individual ego, with the identity 3 deux

substituting for individual identity.

Differences between Twins and Non-Twins

 

Very few of the authors of the case-study material discuss speci-
fic differences between twins and non-twins, except to state that the
presence of the twin complicates the separation-individuation process.
Leonard (1961) concluded that intertwin identification was a major
problem for twins, and that "in the case of every twin whose analysis
has been reported, the twin relationship was considered the prime
reason for that individual's disturbance" (p. 301). Joseph & Tabor
(1961) acknowledge that the twinning reaction can occur between
siblings close in age, between non-twin individuals, and even between
a husband and wife who are married to each other for a long period of
time, but it is less extreme in non-twins than in twins.

Although the problems of fraternal twins do not exactly parallel
those characteristic of identical twins, the same common denominator,
i.e., the presence of another individual in the same phase of develop-
ment, does exist (Burlingham, 1952; Demarest & Winestine, 1955).
Because of this common factor, it is assumed that the fraternal rela-
tionship is comparable to that of identicals in many respects. Thus,
for example, Joseph & Tabor (1961) report that the twinning reaction
occurs in both fraternal and identical twins. Among identical twins,
if they are quite similar in make-up, development, and capabilities,
their problems may relate to too great an attachment to and dependence
on each other, and if they are not alike, any marked differences
between them may put one at a disadvantage over the other (Scheinfeld,

1967). Also, notes Scheinfeld (1967), among fraternal twins, problems

48

may arise from being "trained" to be twins. If they look alike, they
may be under some pressure to be the same in their development and
capabilities, and thus may have greater difficulties than those of
identicals, since they are really no more alike, genetically, than any
two siblings from the same family.

There appears to be a lack of consensus on the similarity between
fraternal opposite-sex twins and other twins. Glenn (1966) is of the
opinion that opposite-sex twins have personality structures similar to
identical and fraternal same-sex twins; his opposite-sex twin clients
exhibited confusion between self and object representations, exaggerated
ambivalence, and a need to recreate the twinship. However, Scheinfeld
(1967) reports that boy—girl pairs are least affected by problems
ordinarily associated with twins. The major difficulties seem to
center around developmental differences; the girl member at birth is
usually ahead of the boy in biological maturity, and her lead is
maintained through puberty. He rates the opposite-sex twins as being
least close, with the degree of closeness highly dependent on the
female partner's efforts to maintain contact.

This concludes the discussion of case study material on the inter-
twin relationship. The studies which are more systematic in that they

involve groups of twins will now be considered.

Systematic Studies of Twin Relationships
The results of systematic studies are presented, in condensed form,
in order to examine differences that have been found between non-twins
and twins on some of the various dimensions of the separation-

individuation process, e.g., dependency, rivalry, ambivalence, and

49

closeness between siblings and twins. Knowledge of these prior

efforts provides a base for the current examination of separation—
individuation. Studies which are particularly relevant are those by
von Bracken (1934), Shields (1954), and Husén (1959) on differences
between fraternal and identical twins; Koch's (1966) study comparing
twin-types to each other and to non-twins; Paluszny & Gibson's (1974)
observations of fraternal twins; and Winestine's (1969) study of
identical twins. (See Table 2.1 for a summary of the different samples
used by each researcher.)

One index of separation-individuation is the degree of attachment
or closeness between the twins. In their studies of young, normal
school-age twins, von Bracken (1934), Shields (1954), and Koch (1966)
all reported that identical twins were more closely attached to each
other than were fraternal twins. Because of the design of Koch's
study, she was also able to compare closeness between non-twins and
twins, and she reported that twins were closer to each other than were
non-twins. Within twin groups, in addition to the previously cited
finding that identicals were closer than fraternals, she found that
fraternal same-sex pairs were closer than fraternal opposite-sex pairs.
As adults, however, the attachment appears to decrease. Husén (1959),
for example, who studied adult male twin pairs, found that while identi-
cals, as compared to fraternals, were more likely to emphasize the
desire to be alike, to be together, and to feel loyal to each other,
the attachment did appear to be less marked as adults than when they
were younger.

An explanation for the varying degrees of closeness between the

twin groups may be found in the amount of competition and rivalry

50

Table 2.l.--Systematic Studies of the Twin Relationship

 

Author(s) and Loca-
tion of Study

Subjects Age of Subjects

 

Husén (1959),
Sweden

Koch (1966), U.S.

Paluszny & Gibson
(1974), U.S.

Shields (1954),
England

von Bracken (1934),
Germany

Winestine (1969),
U.S.

48
47

35

36

19

432

10

36
26

15
12

30

identical pairs 20 yrs.

fraternal pairs

identical pairs 4-7 yrs.

fraternal same-sex
pairs

fraternal opposite-
sex pairs

non-twins matched with
twin pairs on various

demographic variables

fraternal pairs 3-5 yrs.

identical pairs 12-15 yrs.

fraternal pairs

identical pairs 6-16 yrs.

fraternal pairs

identical pairs 8-12 yrs.

 

between twins, which is another indicator of separation-individuation.

Both von Bracken (1934) and Koch (1966) found that the fraternal twin

relationship, as compared to the identical twin relationship, was

characterized by more competition and jealousy between the co-members

of a pair.

When identical twins were involved in competitive tasks,

51

reported von Bracken, they tried to preserve harmony between them-
selves, and if one got ahead of the other on a particular task, the
one who was ahead would either wait for the other twin to catch up,
or even assist his/her twin in the task. This finding was not true of
fraternal twins, who constantly tried to excel their partners on the
tasks. Koch (1966) believes that this marked competitive relationship
within fraternal pairs is the result of the constant comparisons to
which fraternals are subjected. Twins are usually compared excessively,
with identicals scanned for likenesses, and fraternals for differences.
Unfortunately, comparisons based on perceived differences within the
pairs include a less favorable evaluation for one of the twins. In
her opinion, this results in a more stressful relationship for
fraternal twins than for identical twins, and contributes to the lower
attachment between fraternal pairs.

Previous research has indicated a great variance in the degree
of closeness within twin pairs, as might be expected. Paluszny &
Gibson (1974) and Winestine (1969) did not compare various twin-types
for closeness, but instead compared closeness within fraternal pairs,
and identical pairs, respectively. In both studies it was found that
the degree of closeness varied considerably from pair to pair. Thus,
even when examining only fraternal pairs, Paluszny & Gibson (1974)
found that mutual dependency between the pairs varied considerably
from strong, in which one twin spoke for the other and the co-twins
would only play with each other, to almost non-existent, in which each
member of a pair interacted freely with peers and adults when the
opportunity was provided. Winestine (1969), in her study on psycho-

logical differentiation in identical twins, reported a similar variation

52

in the extent of twinning. Some twin pairs were noticeably more
capable than others in interacting with peers, separating from the
twin without anxiety or guilt, perceiving themselves as a whole,

and resolving the competition and jealousy with the twin. Similar
findings were reported by von Bracken (1934) and Shields (1954), and
in some instances they found fraternal pairs who were more closely
attached than other identical pairs.

In summary, these systematic studies reveal that identical twins
are closer to each other than fraternal twins, and fraternal same-sex
twins are closer to each other than fraternal opposite-sex twins.

The fraternal relationship appears to be more competitive than the
identical relationship, and although the degree of attachment between
twins may decrease with age, competitiveness does not appear to.
Finally, there appears to be some variability in the degree of attach-

ment between members of different twin pairs.

Discussion

 

The prime characteristic which distinguishes twins from non-twins
is the close emotional and physical proximity to another individual in
the same phase of development. Because of this proximity, at such an
early age, twins must not only separate and individuate from the mother,
but from the twin as well. From birth, then, the experience of being
a twin is different from that of being a non-twin.

Many of the same characteristics which indicate difficulties with
the separation-individuation process--for example, over-attachment,
dependency, and identity confusion--are also characteristics of the
intertwin relationship. On the basis of the case-study literature, it

was found that the twin relationship usually includes some or all of

53

the following attributes: (a) deleterious effects on ego development
because of cultural and/or parental attitudes which encourage treat-
ment as a "unit" rather than as individuals; (b) identification and
imitation between the partners; (c) dependence; (d) exaggerated
ambivalence; (e) complementary relationships; (f) feelings of lack of
completeness and a disturbed sense of identity; (g) a need to recreate
the twinship with other individuals. Naturally, the extent to which
these characteristics develop or are maintained depends on constitu-
tional factors, and parent-child and twin-twin interactions.

The results of the systematic studies revealed a wide range in
dependency and the extent of the twinning reaction. Overall, however,
comparisons of the twin types revealed that twins were in fact closer
than non-twins, and that the order of closeness within the pairs,
from high to low, was identical, fraternal same-sex, and fraternal
opposite-sex, respectively.

The case study literature, while it is useful for determining any
difficulties which may be inherent in the twin relationship, suffers
from a certain bias in that while many of the twins studied were adults,
many were in psychotherapy, or had been referred for therapy. This
factor necessarily influences what might be considered ”inherent
problems" in the twin relationship, as it does not include a non-
therapeutic analysis of the intertwin relationship. On the other hand,
while the systematic studies that have been done are useful in that the
authors utilized a "more normal" population, with the exception of
Husén's work, all concern young twins. Furthermore, with the exception
of Winestine's study, none have addressed the separation-individuation

process, and even Winestine only included identical twins in her study.

54

Summary

The study of parental patterns and attitudes in transactions with
their children reveal certain salient factors. In this culture, for
the most part, the twinship of both identical and fraternal twins is
accentuated, so that they are frequently referred to as "the twins,"
rather than by their own individual names. Even when differences
between the twins are identified and emphasized by the parents, there
may be "splitting" of the twins between the mother and father, so that
one twin is preferred by the mother and the other by the father. Such
preferences can be detrimental in that they can encourage one twin to
compensate for the loss of the parent by identifying with other members
of the family, particuarly the twin.

In general, twins are subjected to pressures which emphasize their
similarities, closeness, mutual love, and uniqueness. Because of the
presence, from birth, of another individual in the same developmental
phase, it is difficult for twins to establish a clear self-image,
as they tend to identify with each other. Rivalry problems may be
denied or minimized, with the twins adopting the same interests and
sacrificing an individual identity. Jealousy between the twins may
result in hostile death wishes, which in turn must be denied, result-
ing in the twins maintaining their close relationship, and at times
sacrificing outside relationships. All of these factors make twinship
an unusual sibling relationship, and one that is particularly difficult

with which to deal.

CHAPTER III

DESIGN AND METHODOLOGY

Sample

The twin sample for this study was obtained from the Michigan
State University student population. There were about 40,000 students
enrolled at the Michigan State University East Lansing campus in
Spring, 1980, when the data were collected. Because twins occur in
about one of every 80 births, it was estimated that if their college
attendance rate was comparable to that of non-twins, and if both
members of a twin pair attended Michigan State, there was a maximum of
approximately 1,000 twins attending Michigan State.

Signs were posted on bulletin boards in the campus dormitories,
library, and various snack areas throughout campus. All signs were
8 x 14 inches in size and included a statement to the effect that
volunteers were needed for a study on twins, and that the researcher
could be contacted by phone if they were interested in participating in
the study (Appendix A). In addition, two advertisements, comparable to
the signs but smaller in size, were placed in the Michigan State

University newspaper, The State News, one appearing on April 28, 1980,

 

and the other on May 8, 1980 (Appendix B). The advertisement appearing
on May 8 was placed because of a deficit of male twins, especially
fraternals.

Using this procedure, 259 twins, including 48 pairs, contacted the

researcher. A total of 231 questionnaires were returned, for a response

55

56

rate of 89%. Included in these forms were responses from 28 indi-
viduals who were either not students or over the age of 25, responses
from 14 individuals which were incomplete, and responses from three
individuals who were uncertain whether they were identical or fraternal
twins. All of these response forms were eliminated. This left a

balance of 186 forms. The distribution by twin-type was as follows:

 

Twin Pairs .p
Identical female 14
Identical male 6
Fraternal female 6
Fraternal male 0
Fraternal opposite-sex 7

Individual Twins

 

Identical female 22
Identical male 21
Fraternal female 22
Fraternal male 20
Fraternal opposite-sex female 16
Fraternal opposite-sex male 19

The non-twin sample was obtained from classes at Michigan State
University. Responses from 48 people were obtained, of which two were
discarded because of incompleteness. This left a balance of 46 forms,
25 from females and 21 from males.

To obtain the final sample of 160 subjects, 20 males and 20
females from each group, i.e., non-twins (NT), identical twins (ID),

fraternal same-sex twins (F33), and fraternal opposite-sex twins (FOS),

57

were selected at random. While twins from twin pairs were included
in the selection process, care was taken to ensure that only 92g.
member of a pair was included in the final sample. (There was no
random selection of the 20 fraternal same-sex male twins because there
were only 20 of them available.) The average age of all respondents
was 20.5 years; most respondents (92%) were single; and most of them
did not live at home (82%) or with their twin or closest sibling (85%)
(Table 3.1). The groups are similar across a number of demographic
variables; exceptions to this finding are that 35% of the identical
twins stated that they lived with each other, which is a higher per-
centage than that of the other groups; and 47.5% of identical twins
stated that their twin was attending the same school as they were,
which is, again, a higher percentage than those of the other groups

(Table 3.2).

Instrumentation

 

Separation-Individuation Instrument

 

The instrument used in this study to measure separation-
individuation was derived from the instrument used by Maroda (1979)
in her research on separation anxiety in adults. Her instrument,
Form A (Appendix C), contained 143 items, some of which lack clarity.
Because of this factor, and because the degree of internal consistency
of some of the clusters was moderately low, it was decided to revise
Form A before administering it to the persons to be used in this study.
Included in the revision of the instrument was a consideration of
response styles. While an equal number of items phrased in positive

and negative directions was not possible because of distortion of the

58

Table 3.l.--Demographic Information on the Complete Sample

 

Agea _fl (%)
18 21 (13.1)
19 39 (24.4)
20 26 (16.2)
21 31 (19.4)
22 19 (11.9)
23 ll ( 6.9)
24 3 ( 1.9)
25 10 ( 6.3)

Race
Black 16 (10.0)
White 143 (89.4)
Other 1 ( .6)

Marital Status
Single 148 (92.5)
Married 5 ( 3.1)
Living with someone

romantically in-
volved with, but
not married 7 ( 4.4)

Live at Home
Yes 29 (18.1)
No 131 (81.9)

Live with Twin or
Sibling
Yes 24 (15.0)
No 136 (85.0)

Twin or Sibling
Attending Same
School
Yes 40 (25.0)
No 120 (75.0)

 

8The average age of the entire sample was 20.5 years.

59

 

Am.N V a o o o porno
Am.NmV Nm Am.NaV NN No.omV om Am.NwV mm mNNez
No.n V N Am.N V N No.0NV q Nm.NNV N NumNm
comm
No.m V N An.N V m No.n V N Am.N V m mN
o An.N V N o No.m V N «N
No.oNV a No.m V N Am.N V N No.0NV s NN
No.0NV a No.m V N No.oNV N AN.NNV m NN
No.omV NN No.oNV m Am.NNV N No.0NV a NN
No.oNV e No.oNV N Am.NNV a Am.NNV m oN
Am.NNV a Am.NNV NN No.mNV ON Am.NNV A NN
Am.NNV m Am.NNV m Nm.N V m No.oNV N NN
I. I. .I .I mmw<
NNV a NNV : NNV a NNV a
aNze mom cN3N mme :Nze oN cN3N-coz

oa>e CH3H

 

ma>e GNBH an mamemm

map so COHumeuowcH ownamquEmall.N.m manna

60

.mumm% o.om wm3 mcw3u mom mo mwm mwmum>m mzu mam “mummm m.oN mmz mafisu mmm mo own mwmum>m

msu momma» c.0m mm: mafl3u QH mo own mwmum>m mnu "munch o.om mm3 mcw3ulco: msu mo own mwmum>m open

 

 

No.owV Nm Am.NNV Nm Am.NmV NN No.oaV om oz
Ao.o~V m Am.NNV m Am.mqV mN Ao.oHV q no»
Hoonow memm wcw
neamNN< chNNNm No aNae
Am.NmV mm Ao.me cm Ao.moV om Am.mmV mm oz
Am.m V m Ao.mHV c Ao.mmV «a Am.N V H mm»
chNnNm No aNse saws m>NN
Am.~mV mm Am.NwV mm Am.NmV mm Ao.owV mm oz
Am.N V m Am.NNV N Am.NNV NN No.oNV N was
meow um m>NA
o o Ao.m V N Am.n V m mmwuume Nos Nan .nufla
om>ao>cfl >Hamowucm80u
mcomaom zuHB wcH>HA
Am.N V H Ao.oaV a Am.m V a Am.m V H vofiuumz
Am.moV mm Ao.omV om Am.NmV mm Ao.ooV om onsHm
mnumum Hmufiumz
NNV Am ANV : NNV a NNV :
cN3H mom :NBH mmm CH3H DH :HBBIcoz
ma%e CNBH

 

NewsaNNaouV N.m mNnme

61

meaning of the item, about one—third of the items were negatively
worded. This wording was used so that persons with an acquiescence
set did not obtain scores simply by their tendency to say "true"
instead of "false" to any question put to them (Berg, 1967; Sundberg,
1977). It was decided to retain the same response format as that used

by Maroda. Thus, a response of "one indicated that the respondent
found the item to be "completely true"; a response of "two" that the
item was "mostly true"; a "three" that the item was "mostly false";

and a "four" that the item was "completely false."

A new form of the instrument, Form B (Appendix D), containing 100
items, was derived and administered to 211 college students during
Summer Term, 1979, at Michigan State University. A background question-
naire (Appendix E) was also given with this instrument. An analysis of
the data included the elimination of items which were not discriminat-
ing among individuals (for example, almost 100% of the sample answered
the question, "I love to eat" with "completely true"), followed by a
cluster analysis of the remaining items. The cluster analysis yielded
five clusters (Appendix F), with measures of internal consistency
ranging from .72 to .84 (Appendix G).

The first cluster, Individuation I-Past, with a standard score
coefficient alpha of .75, is composed of items which reflect school
attendance behaviors, stranger anxiety, and other indicators of
separation-individuation. For example, included are "When I was in
elementary school one of my parents would want to take me to school,"
and "From the very first day of kindergarten I enjoyed school and

couldn't wait to go."

62
The second cluster, Individuation II - Present Status, with a
standard score coefficient alpha of .84, is composed of items which
concern current relationships with other people, including feelings of
rejection, acceptance of others, guilt, dependence, and how independent
a person perceives him-/herself to be. Included in this cluster, for
example, are "I fear that I will be rejected by people I really care

' and "I don't depend on

about if I express hostility toward them,‘
others too much for my happiness."

The third cluster, Father Involvement, with a standard score
coefficient alpha of .83, is an experimental cluster. There has been
very little research on the impact of the father on the separation-
individuation process, but the research on this subscale by Maroda
(1979) provided some evidence that the father should not be ignored.
This cluster includes, for example, the items "I am very close to my
father," and "My father was deeply involved in the emotional life of
our family."

The fourth cluster, Family Rivalry, with a standard score
coefficient alpha of .72, contains items which reflect the relation-
ships in the family unit. This subscale has the lowest coefficient
alpha of all of the subscales. Included in this subscale are such

' and "There was

items as "I have said terrible things to my mother,’
hardly any sibling rivalry in my family."

The final cluster, Body Image, with a standard score coefficient
alpha of .74, contains a variety of self-descriptive items concerning

a person's image of him-lherself. For example, the items, "I am not

too fat or too thin," and "I think I am sexy" are in this cluster.

63

These five clusters contain a total of 60 items, and while it was
originally thought that these 60 items could be taken, by themselves,
and used as the new instrument, an examination of such an instrument
revealed that it might have a negative impact on the subjects because
most of the questions appeared to be "highly charged" emotional items.
Therefore, the new form of the instrument, Form C (Appendix H), is
composed of the same items that were used in Form B, with the following

' was eliminated

exceptions: (a) item 75, "I have never been shy,‘
because it was a duplicate of item 25 (an inadvertent error on the part
of the researcher); (b) item 95 was changed from "I don't think I'm
very attractive” to "I don't think I'm very attractive/handsome,"
thus eliminating the perceived sexual bias in the term "attractive";
(c) grammatical corrections were made in items 10, 33, 68, 70, 77, and
79. Thus, Form C contains 99 items and is quite similar to Form B.

For the scoring of the instrument, a format comparable to
Maroda's (1979) was used. After reversing the values of the items

which were negatively worded, the scores for each subscale were summed

and then divided by the number of items on that particular subscale.

Because a "one" or "two" response indicated that the item was

"completely true" or "mostly true,‘ respectively, a low score repre-

sents less separation-individuation than a high score.

Backgroundeuestionnaire

 

In designing the two background questionnaires, one for use with
the twins and the other for use with the non-twins, an attempt was
made to ask questions which could be used with both groups. Another

consideration in the design of the questionnaire was length; while

64

more questions could have been asked, it was decided that three pages
was a reasonable but maximum length.

Included on the Twin Background Questionnaire (Appendix I) were
questions concerning basic demogrphic variables, such as age, race,
and sex. Also included were questions concerning school attendance and
fear of going to school, as these are indicators of problems in the
separation-individuation process (Maroda, 1979). Questions about
residence, dress, alliterative names, a secret language, closeness to
the twin, and feelings about being a twin were also asked.

Zygosity was determined by inquiring about the sex of the twin
(item 9), the similarities between the twins in eye color, body build,
blood type, hair color, and hair texture (item 23), and a direct
question concerning twin type (item 24). The questions asked were
similar to those used by Claridge, Canter, & Hume (1973), who found
that answers to such questions were consistent with medical tests
used to determine zygosity, and were thus highly accurate in dis-
criminating between identical and fraternal twins.

It is encouraging that even quite crude information about

physical similarity allows zygosity to be determined with

an acceptably low degree of error. Certainly the error,

though not quantifiable, is likely to be so small as to

have little material effect on the results of statistical
studies of twins using reasonably large samples. (pp. 16-17).

Included on the Background Questionnaire (Appendix J), which was
used for the non-twin sample, were the same questions concerning
demographic variables and school attendance. The difference between
this questionnaire and the Twin Background Questionnaire was that,
instead of inquiring about dress, alliterative names, a secret

language, and closeness to the twin, the same questions were asked

65

about the closest sibling. In addition, there were no parallel
questions for non-twins about feelings of being a twin nor the

physical resemblance to the twin.

Procedure

Originally, the questionnaires were to be individually adminis-
tered, but with the large number of respondents this procedure was
deemed unfeasible. Instead, when a twin called the researcher, the
purpose and other details of the study were briefly explained; this
explanation included that it was a study on twins; that there were two
questionnaires to complete; that it involved about 20 to 30 minutes
of time at any time within the next week; that there was to be a
$50.00 prize for one of the twins, selected at random, who partici-
pated in the study; and that responses were anonymous. At this
point, twins were asked whether they were still interested (only one
twin said no), and, if so, they were told that the forms would be
mailed to them if they lived off campus, and placed in their dormitory
mailbox if they lived on campus. Within the same or next day, the
forms were placed in the mail or delivered to the dormitories. About
one-half of the twins who called lived off campus, and the other half
on campus.

Accompanying the questionnaires were a sheet of directions
(Appendix K), including a note to call the researcher if the directions
were not clear; an answer sheet; a self-addressed, stamped envelope in
which to return the questionnaires; and a postcard to be returned to
the researcher to provide feedback to the respondents. The separate

mailing of the responses to the questionnaires and the postcard

66

ensured anonymity and, in addition, it enabled the researcher to
contact those twins who had not completed the questionnaire within

10 days. If the forms were not returned within this period, twins
were contacted and encouraged to respond if at all possible. How-
ever, this procedure was not necessary in most instances, and it was
useful in that it enabled the researcher to ensure respondent receipt
of the questionnaires.

Returned questionnaires were examined for completeness, and if
they were incomplete, they were discarded. In addition, if the
respondent was not in the predefined category of student and between
the ages of 18 and 25, the form was not used. Then the response to
the question concerning twin—type (item 24) on the background
questionnaire was examined for appropriateness of response; contra—
dictory information on this item (e.g., if the respondent had
indicated that the twin was of the opposite sex, but had checked
"identical" as twin-type) led to elimination of the form. Similarly,
if the respondent indicated that the twin had differing eye color,
body build, blood type, hair color, or texture of hair (item 23),
but checked "identical" as twin-type, the form was discarded. Thus,
only those identical twins who checked "yes" to all the criteria on
the physical similarity items were included in the identical twin
sample. Finally, if the twin indicated that he/she was "uncertain" as
to twin-type (item 24), the form was discarded. The responses on the
separation-individuation instrument were also examined for complete-
ness; in general, if the respondent had left more than five questions
unanswered, the form was discarded. The only exception to this was

if the respondent had no father and was unable to answer the Father

67

subscale questions; these forms were included in the final sample.
Forms that were consistently answered were then coded for twin type,
and the responses for both questionnaires were placed on computer

scoring sheets.

Analysis

This study involved four groups of subjects: 40 non-twins,

40 identical twins; 4O fraternal same-sex twins, and 40 fraternal
opposite-sex twins. Separation-individuation was assessed using the
separation-individuation instrument. Thus, the independent variable
was twin-type, and the dependent variable was the score on the
separation-individuation subscales.

Because there was a specific and limited number of hypotheses
to be tested, with the comparisons being both a priori and orthogonal,
the data were analyzed with the p-ratio. Each comparison was
evaluated at the .05 level of significance, with the conceptual unit
for the significance level being the individual comparison. Because
the number of degrees of freedom associated with the MS error was
sufficiently large, the tests of significance can, for all practical

purposes, be regarded as independent (Kirk, 1968).

Hypotheses

 

H91: No difference will be found in separation-individuation as
measured by the separation-individuation instrument between non-twins
and twins.

Hal: The non-twin mean score on a measure of separation-

individuation will exceed that of twins.

68

H9_ No difference will be found in separation-individuation

2 ‘ _
as measured by the separation-individuation instrument between
fraternal and identical twins.

Ha_ The fraternal twin mean score on a measure of separation-

2:
individuation will exceed that of identical twins.

H93: No difference will be found in separation-individuation as
measured by the separation-individuation instrument between fraternal
opposite-sex and fraternal same-sex twins.

-§§3' The fraternal opposite-sex twin mean score on a measure of

separation-individuation will exceed that of fraternal same-sex twins.

Summary

In this study of separation-individuation, 40 non-twins, 40
identical twins, 40 fraternal same-sex twins, and 40 fraternal
opposite-sex twins completed a separation—individuation instrument.
All of the participants were college students between the ages of 18
and 25. The hypotheses were evaluated using planned orthogonal

contrasts, and the results are discussed in the next chapter.

CHAPTER IV

RESULTS

This study was designed to (a) assess the extent of separation-
individuation in twins as compared to non-twins, (b) assess the
extent of separation-individuation in identical twins as compared to
fraternal twins, and (c) assess the extent of separation-individuation
in fraternal same-sex twins as compared to fraternal opposite-sex twins.
In addition, based on the above design, the validity of the separation-
individuation instrument itself was to be assessed.

The sample consisted of 40 non-twins, 40 identical twins,
4O fraternal same-sex twins, and 40 fraternal opposite-sex twins.
Based on the literature review on twins, a set of three orthogonal
planned comparisons was formulated to test the hypotheses; these
hypotheses were tested using the p-ratio, with the probability of
significance set at the .05 level.

The results of the three major hypotheses tested in this study,
stated in the alternative form, follow. In the tables accompanying
the results, the subscale Individuation I-Past was abbreviated to
Past, the Individuation II-Present Status subscale was abbreviated to
Present, and the Family Rivalry subscale was abbreviated to Rivalry.
The reader is reminded that high mean scores on subscales indicate
£2333 difficulties in separation-individuation than low mean scores.
The mean subscale scores on the separation-individuation instrument by

twin-type are presented in Table 4.1.

69

Table. 4.1.--Cell Means and Standard Deviations by Twin-Type on the

Five Subscales of the Separation-Individuation Instrument

 

 

Subscale ‘3 Mean S.D.
Past
NT 39 2.8513 .3556
ID 40 2.9100 .3718
F85 39 3.0308 .2820
F08 40 2.9250 .3949
Present
NT 40 2.5437 .3219
ID 40 2.3888 .3819
F88 40 2.4487 .4017
F08 40 2.4150 .4474
Father
NT 40 2.9056 .4184
ID 40 2.8833 .6204
F88 39 2.9031 .5181
F08 38 3.8830 .5689
Rivalry
NT 40 2.8361 .4173
ID 40 2.9889 .3448
F88 39 2.8547 .3748
F08 38 2.8830 .4791
Body Image
NT 40 2.8893 .3291
ID 40 2.8786 .4311
F88 40 2.8964 .3759
PCS 40 2.8571 .4970

 

71

Hypotheses Tests

 

1a

The non-twin mean score on a measure of separation-
individuation will exceed that of twins.

Out of the five subscales on the separation-individuation instru-
ment, only one, Individuation II-Present Status, produced significant
findings (Table 4.2). On this subscale, twins scored lower than the
non-twins, indicating that twins were less separate and individuated
than non-twins. On the remaining subscales, there were no differences
between twins and non-twins. On two subscales, Individuation I-Past,
and Family Rivalry, the mean of the twins exceeded that of the non-

twins, although not significantly.

53-2

The fraternal twin mean score on a measure of separation-
individuation will exceed that of identical twins.

No significant differences were found between identical and
fraternal twins on any of the five subscales (Table 4.3). On four of
the five subscales, the means were in the predicted direction, i.e.,
identical mean scores were below fraternal mean scores, but this was

not true on one subscale, Family Rivalry.

Ha

The fraternal opposite-sex twin mean score on a measure of
separation-individuation will exceed that of fraternal same-
sex twins.

Comparisons between fraternal same-sex and fraternal opposite-
sex twins revealed no significant differences on any of the five

subscales (Table 4.4). On four of the five subscales, fraternal

Table 4.2.--Ce11 Means and Tests of Significance of Differences
between Non-twins (NT) and Twins (T) on the Separation-
Individuation Instrument

72

 

 

Subscale n Mean MS df t
__ -nw ___ __

Past
NT 39 .8513 .1253 154 -l.592
T 119 .9546

Present

*

NT 40 .5437 .1527 156 1.769
T 120 .4175

Father
NT 40 .9056 .2877 153 .160
T 117 .8898

Rivalry
NT 40 .8361 .1651 153 - .978
T 117 .9098

Body Image
NT 40 .8893 .1706 156 .158
T 120 .8773

 

*
p< .05

73

Table 4.3.--Cell Means and Tests of Significance of Differences

between Identical Twins (ID) and Fraternal Twins (F)
on the Separation—Individuation Instrument

 

 

Sub scale p Mean EW _d_f_ _t_

Past
ID 40 2.9100 .1249 116 .990
F 79 2.9772

Present
ID 40 2.3888 .1691 117 .542
F 80 2.4318

Father
ID 40 2.8833 .3262 114 .088
F 77 2.8931

Rivalry
ID 40 2.9889 .1620 114 -l.530
F 77 2.8687

Body Image
ID 40 2.8786 .1914 117 .021
F 80 2.8768

 

74

Table 4.4.--Cell Means and Tests of Significance of Differences
between Fraternal Same-Sex Twins (F85) and Fraternal
Opposite-Sex Twins (FOS) on the Separation-Individuation

 

 

Instrument
Subscale n Mean MSw df t
Past
FSS 39 3.0308 .1182 77 -l.370
FOS 40 2.9250
Present
FSS 40 2.4487 .1807 78 - .355
FOS 40 2.4150
Father
FSS 39 2.9031 .2957 75 - .162
FOS 38 2.8830
Rivalry
FSS 39 2.8547 .1844 75 .290
FOS 38 2.8830
Body Image
FSS 40 2.8964 .1941 78 - .399

FOS 40 2.8571

 

75

same-sex mean scores exceeded fraternal opposite-sex mean scores, but
on the Family Rivalry subscale, the reverse was true, i.e., the mean
was in the predicted direction.

Overall, out of the 15 comparisons, only one, twins as compared

to non-twins on the Individuation II-Present Status, was significant.

Additional Results

 

In addition to the exploration of differences in separation-
individuation that exist between non-twins and twins, it will be
recalled that a purpose of this study was to investigate the validity
of the separation-individuation instrument. While no formal
hypotheses concerning the validity were formulated, questions were
included on the background questionnaire which would help to assist
in the evaluation of the validity of the instrument. The data were
analyzed using a one-way analysis of variance, with the probability
of significance set at the .05 level. The comparisons between
groups in this section do not concern differences between twins and
non-twins, but between groups delineated on the basis of differences
in school attendance, sex, residence with the twin or closest
sibling, and other variables.

The first comparison involved respondents who reported fear of
going to school as a child as opposed to those who did not report fear
of going to school as a child. Based on the findings of Maroda (1979),
this researcher would predict that those who were afraid to go to
school as a child would score significantly lower on the instrument
subscales than those who were not afraid to go to school as a child,

as fear of going to school appears to be one of the initial indicators

76

of possible separation-individuation difficulties. While the mean
subscale scores were in the predicted direction on the Father and
Family Rivalry subscales, they were not significantly different from
each other (Table 4.5 and Table 4.6). The results of the analysis of
variance showed that the expected results occurred on three of the
five subscales, including Individuation I-Past, Individuation II-
Present, and Body Image.

The second question which provided information on the validity
of the instrument concerned frequency of absence from school. On the
basis of Maroda's (1979) findings, this researcher predicted that
those who missed school more often than most children would score
significantly lower on the instrument than those who missed school
less often than most children. While the original intention was to
compare these two groups, there were few respondents (p = 7) who
reported missing school more often than most children. Thus, it was
decided to merge the "more often" and "average amount" groups and to
compare this group to the "less often" group. The means for
Individuation II-Present, Father, and Family Rivalry subscales were
in the predicted direction, but were not significantly different
(Table 4.7 and Table 4.8). The analysis of variance revealed that
only the Individuation I—Past subscale was significant.

A third analysis of variance involved the sex of the participants.
Maroda (1979) found some evidence that females had more difficulties
with separation-individuation than did males. In this study, how-
ever, this was not found to be the case except on the Family Rivalry
subscale, in which the male mean score exceeded the female mean

score (Table 4.9 and Table 4.10). (A two-way analysis of variance

77

Table 4.5.--Ce11 Means and Standard Deviations for All Subjects on
the Five Subscales of the Separation-Individuation
Instrument on the Variable of Childhood Fear of Going
to School

 

Twin Background Questionnaire Item 7/Background Questionnaire Item 7:
"There were times when I was afraid to go to school as a child:

 

Yes
NO"
Subscale ‘3 Mean Standard Deviation
Past
Yes 42 2.6159 .2911
No 116 3.0425 .3074
Present
Yes 44 2.3057 .4092
No 116 2.5034 .3722
Father
Yes 43 2.8191 .5582
No 114 2.9220 .5205
Rivalry
Yes 44 2.8409 .4649
No 113 2.9105 .3823
Body Image
Yes 44 2.7078 .4280

No 116 2.9458 .3841

 

78

Table 4.6.--Ana1ysis of Variance on Childhood Fear of Going to School
as a Child for All Subjects on the Five Subscales of the
Separation-Individuation Instrument

 

 

**p < .001

Subscale

Past
Source SS SS MS S
Between 5.6131 1 .6131 61.0650**
Within 14.3396 156 .0919

Present
Source SS_ gf_ {MS .S
Between 1.2477 1 .2477 8.5228*
Within 23.1297 158 .1464

Father
Source _SS 19S MS_ _E
Between .3306 l .3306 1.1727
Within 43.7025 155 .2819

Rivalry
Source .SS .QE ‘MS 'S
Between .1535 l .1535 .9270
Within 25.6606 155 .1656

Body Image
Source SS 1S: .MS .2
Between 1.8073 1 .8073 ll.4949**
Within 24.8412 158 .1572

*p < .005

79

Table 4.7.-—Cell Means and Standard Deviations for All Subjects on the
Five Subscales of the Separation-Individuation Instrument
on the Variable of Missed School as a Child

 

Twin Background Questionnaire Item 8/Background Questionnaire Item 8:
"As a child I missed school: ___ less often than most children.

an average amount.

___more often than most children.

E. Mean S.D.
Subscale
Past
Less often 105 .9879 .3241
Average/more often 53 .8126 .3909
Present
Less often 107 .4607 .4063
Average/more often 53 .4255 .3626
Father
Less often 104 .9017 .5119
Average/more often 53 .8784 .5721
Rivalry
Less often 104 .9049 .3844
Average/more often 53 .8637 .4501
Body Image
Less often 107 .8785 .4413
Average/more often 53 .8841 .3397

 

80

Table 4.8.--Analysis of Variance on Missed School as a Child for All

Subjects on the Five Subscale of the Separation-

Individuation Instrument

 

Subscale

Past

Present

Father

Rivalry

Body Image

Source

Between

Within

Between

Within

Between

Within

Between

Within

Between

Within

18

24

26

.0831
.8697

.0441
.3333

.0191
44.

0141

.0595
25.

7546

.0011
.6474

156

158

155

155

158

m

1.0831

.1210

.0441
.1540

.0191
.2840

.0595
.1662

.0011
.1687

IM

8.954*

.286

.067

.358

.007

 

p < .005

81

Table 4.9.--Ce11 Means and Standard Deviations for All Subjects on the
Five Subscales of the Separation-Individuation Instrument
on the Variable of Sex

 

 

Subscale .g Mean S.D.
Past

Female 80 .9009 .3632

Male 78 .9567 .3499
Present

Female 80 .4325 .3982

Male 80 .4656 .3866
Father

Female 79 .9128 .5592

Male 78 .8746 .5044
Rivalry

Female 80 .8264 .4305

Male 77 .9582 .3716
Body Image

Female 80 .8857 .4107

Male 80 .8750 .4106

 

82

Table 4.10.--Analysis of Variance on Sex for All Subjects on the
Five Subscales .of the Separation-Individuation Instrument

 

Subscale

Past

Present

Father

Rivalry

Body Image

Source

Between

Within

Between

Within

Between

Within

Between

Within

Between

Within

19.

24.

43.

25.

.1230

8297

.0439

3335

.0571

9760

.6812

1329

.0046

.6439

156

158

155

155

158

.1230

.1271

.0439

.1540

.0571

.2837

.6812

.1621

.0046

.1686

Id

.9678

.2850

.2014

4.2011*

.0272

 

p < .05

83

revealed no interaction between twin-type and sex on any of the five
subscales of the separation-individuation instrument.)

Further analyses of the data were based on other comparisons of
groups delineated on the basis of responses on the background
questionnaire. It was found that separation-individuation was not
related to (a) residence with the twin or closest sibling,

(b) attendance at the same school with the twin or closest sibling,

(c) parental emphasis of similarities or differences between the twins,
(d) alliterative names, (e) a secret language between the twins, or

(f) dressing alike in elementary or high school. While it had been
planned to compare those groups who rated themselves ”not close at all”
to their twin or closest sibling to those who rated themselves
"extremely close" to their twin or closest sibling, none of the

"not close at all" on the seven—point

respondents rated themselves as
scale that was utilized to measure closeness. Because of the low
number of respondents who rated themselves as somewhat less than
"moderately close," it was necessary to compare those who rated them-
selves "extremely close" (a "seven" on the seven-point scale) to

those who rated themselves less than "moderately close" (a "two,"
"three," or "four" on the seven-point scale). Using these two criterion
groups, it was found that separation-individuation was not related to
rated closeness to the twin or closest sibling. However, comparison

of those who dressed alike currently to those who never dressed alike

currently revealed a significant difference on the Individuation I-Past

subscale (Table 4.11 and Table 4.12).

84

Table 4.11.--Ce11 Means and Standard Deviations for All Subjects on the
Past Subscale of the Separation-Individuation Instrument

 

Twin Background Questionnaire Item 17/Background Questionnaire Item 16:
"Currently, my twin/closest sibling and I dress alike:

___ Almost always
Frequently
Sometimes
Hardly ever

Never"

Subscale ‘p (M333 §L£L_
Past
Almost always, frequently,
sometime, hardly ever 44 2.8288 .3302
Never 114 2.9678 .3601

 

Table 4.12.--Analysis of Variance on Currently Dressing Alike for all
Subjects on the Past Subscale of the Separation-
Individuation Instrument

 

M _s_§ :1: m E.
Subscale
Past Between .6138 l .6138 4.951*
Within 19.3389 156 .1240

 

*p< .05

85

Descriptive Material on Twins and Non-Twins

 

The remainder of this chapter concerns the frequency of responses
to various items on the background questionnaires that were asked to
investigate similarities and differences between twins and non-twins.
The responses to questions that were asked of both twins and non-twins
will be discussed first, and then the responses to the questions that

were asked of only the twin sample will be examined.

Frequency of Alliterative Names

 

In chapter two, it was noted that twins are frequently given
alliterative names to emphasize their twin status, and both the twin
and non-twin sample were asked whether they had alliterative names.
About 65% of the twins had alliterative names, and 20% of the non-
twins reported having alliterative names (Table 4.13). Overall, about
66% of the female twins and 50% of the male twins reported having

alliterative names.

Frequency of Dressing Alike

 

Another method to emphasize the twin relationship is to dress
like the twin, and twins and non-twins were asked about their fre-
quency of dressing alike in elementary school, high school, and
currently. In elementary school, neither the non-twins nor the
fraternal opposite-sex twins always dressed alike, and only 15% of the
identical and 20% of the fraternal same-sex twins always dressed alike
(Table 4.14). About 70% of both the non-twins and fraternal opposite-
sex twins never dressed alike. About 10% of the male twins and 25%
of female twins reported always dressing alike, while about 28% of

both male and female twins never dressed alike.

86

Table 4.13.--Frequency of Alliterative Names by Twin-Type and Sex

 

Twin Background Questionnaire Item 14/Background Questionnaire Item 13:
"My twin/closest sibling and I have twin-type or alliterative names
(for example, Jill and Jane, Judy and Jack, or Robert and Ronald):

 

 

 

 

.___ Yes
___.No"
Bag E99211; M (7.)
Non-twin
Yes 5 3 8 (20.0)
No 15 17 32 (80.0)
Identical twin
Yes 9 14 23 (57.5)
No 11 6 17 (42.5)
Fraternal same-sex twin
Yes 11 13 24 (60.0)
No 9 7 16 (40.0)
Fraternal opposite-sex twin
Yes 9 13 22 (55.0)

No 11 7 18 (45.0)

 

87

Table 4.14.--Frequency of Dressing Alike in Elementary School by
Twin-Type and Sex

 

Twin Background Questionnaire Item lS/Background Questionnaire Item 14:
"During elementary school, my twin/closest sibling and I were dressed
alike: Almost always

 

 

 

 

Frequently
Sometimes
Hardly ever
Never"
Male Female Total (%)
Non-twin
Almost always 0 0 0 ( .0)
Frequently O 2 2 ( 5.0)
Sometimes 3 l 4 (10.0)
Hardly ever 4 l 5 (12.5)
Never l3 16 29 (72.5)
Identical twin
Almost always 2 4 6 (15.0)
Frequently 4 4 8 (20.0)
Sometimes 7 5 12 (30.0)
Hardly ever 3 6 9 (22.5)
Never 4 l 5 (12.5)
Fraternal same-sex twin
Almost always 2 6 8 (20.0)
Frequently 3 6 9 (22.5)
Sometimes 7 3 10 (25.0)
Hardly ever 7 5 12 (30.0)
Never 1 O ( 2.5)
Fraternal opposite-sex twin
Almost always 0 0 0 ( .0)
Frequently O 0 0 ( .0)
Sometimes l l 2 ( 5.0)
Hardly ever 7 3 10 (25.0)
Never 12 16 28 (70.0)

 

88

In high school, most twins were not dressing alike; only one of
the identical female twins always dressed like her twin (Table 4.15).
Slightly more than 80% of the non-twins and fraternal opposite-sex
twins never dressed alike, while about 30% of the identical and
fraternal same-sex twins hardly ever dressed alike. About 60% of male
twins and 70% of female twins reported never dressing alike.

At the time of this study, there was only one twin, an identical
female, who reported always dressing like her twin (Table 4.16). The
dressing patterns appeared to be quite similar between the four
groups, with about 75% of both male and female twins reporting never
dressing alike.

Initially, then,the dressing patterns of identical and fraternal
same-sex twins resembled each other, and those of the non-twins and
fraternal opposite-sex twins resembled each other. With time, however,
all four groups of twins came to resemble one another in their dressing
patterns, with most of the non-twins and twins not dressing like their

closest sibling or twin.

Frequency of a Secret Language

 

In chapter two, it was reported that unique communication patterns,
or a secret language, may develop between twin pairs. In this study,
60% of the identical twins reported the existence of a secret language
with their twin (Table 4.17). This was a considerably higher inci-
dence than that reported by fraternal same-sex twins (28%), which was
in turn higher than that reported by fraternal opposite-sex twins
(12%). A secret language appeared to be about as common among male

twins as among female twins.

89

Table 4.15.--Frequency of Dressing Alike in High School by Twin-
Type and Sex

 

Twin Background Questionnaire Item l6/Background Questionnaire Item 15:
"During high school, my twin/closest sibling and I dressed alike:

Almost always

 

 

 

 

Frequently
Sometimes
Hardly ever
Never"
Male Female Total (%)
Non-twin
Almost always 0 0 0 ( .0)
Frequently O 0 O ( .0)
Sometimes 3 0 3 ( 7.5)
Hardly ever 1 3 4 (10.0)
Never l6 17 33 (82.5)
Identical twin
Almost always 0 l l ( 2.5)
Frequently l 0 l ( 2.5)
Sometimes 2 l 3 ( 7.5)
Hardly ever 7 5 12 (30.0)
Never 10 13 23 (57.5)
Fraternal same-sex twin
Almost always 0 O 0 ( .0)
Frequently 0 0 0 ( .0)
Sometimes 2 4 6 (15.0)
Hardly ever 9 4 13 (32.5)
Never 9 12 21 (52.5)
Fraternal opposite-sex twin
Almost always 0 O O ( .0)
Frequently 0 O 0 ( .0)
Sometimes 0 1 l ( 2.5)
Hardly ever 3 2 5 (12.5)
Never 17 17 34 (85.0)

 

Table 4.16.-—Frequency of Currently Dressing Alike by Twin-Type

and Sex

90

 

Twin Background Questionnaire l7/Background Questionnaire Item 16:

"Currently, my twin/closest sibling and I dress alike:

Almost always
Frequently
Sometimes

Hardly ever

Never"

Non-twin

Almost always
Frequently
Sometimes
Hardly ever
Never

Identical twin

 

Almost always
Frequently
Sometimes
Hardly ever
Never

Fraternal same-sex twin

 

Almost always
Frequently
Sometimes
Hardly ever
Never

Fraternal opposite—sex twin

 

Almost always
Frequently
Sometimes
Hardly ever
Never

Male

bU‘l-‘OO DWWOO DNJ—‘OO

CDNOOO

Female

DO‘OOO LJ'INNOH NHLNJJ-‘O

O‘NNOO

Total

CDHI-‘OO \DLfikfiOH C‘WVJ-‘O

NH

bbNOO

 

( 2.
.0)
(12.
.5)
.5)

(12
(72

AAAAA
OVN

AAA/\A
LflOUI

.0)
.0)
.5)
.5)
.0)

5)

5)

.0)
.0)
.5)
.5)
.O)

.0)
.0)
.0)
.0)
.0)

 

91

Table 4.17.--Frequency of a Secret Language by Twin-type and Sex

 

Twin Background Questionnaire Item 18/Background Questionnaire Item 17:
"As youngsters, my twin/closest sibling and I had our own secret
language which others could not understand:

 

 

 

 

.___ Yes
____No
me 2121. me}. (2)
Non-twin
Yes 1 1 2 ( 5.0)
No 19 19 38 (95.0)
Identical twin
Yes 14 10 24 (60.0)
No 6 10 16 (40.0)
Fraternal same-sex twin
Yes 6 5 11 (27.5)
No 14 15 29 (72.5)
Fraternal opposite-sex twin
Yes 1 4 5 (12.5)

No 19 16 35 (87.5)

 

92

Closeness to the Parents

 

In chapter two, it was stated that some twins are "split" between
the two parents, either because of a parental preference for one twin
over the other, or because one twin claims or appropriates the mother,
and the other the father. To determine the extent of the frequency
of this occurrence, both twins and non-twins were asked which parent
they were closer to, and which parent their twin or closest sibling
was closer to. It was found that for about 75% of the twins, both
members of a twin pair were closer to the same parent, with most being
closer to their mother (Table 4.18). This was also true of the non-
twin sample. The splitting of the parents occurred least frequently
in the case of identical twins: only six identical twins reported
instances in which one twin was closer to the mother and the other to

the father, or vice versa.

Closeness between Twins and Non-Twins

 

In the discussion of the intertwin relationship, it was seen that
there appeared to be varying degrees of closeness between twins, and
between twins and non-twins. Both the twin and non-twin samples were
asked to rate their closeness to each other on a 7-point scale, with

"one" indicating "not close at all,".a ”four" indicating "moderately

' and a "seven" indicating "extremely close." The entire sample,

close,‘
both twins and non-twins, rated themselves, on the average, as being
more than "moderately close." In order of closeness, the identical

twins rated themselves as being closest, followed by fraternal same-

sex twins, fraternal opposite-sex twins, and non-twins (Table 4.19).

An analysis of variance by rating of closeness, followed by post hoc

93

Table 4.18.--Frequency of Closeness to the Same or Different Parent
by Twin-Type

 

Twin Background Questionnaire Items 19 & 20/Background Questionnaire
Items 18 & 19: "I am closer to (choose only one):

My mother

My

My twin/closest sibling is closer to (choose only one):

father

My mother

My

father"

Group

NT

Both closer to

Mother (20)
Father ( 4)

Each closer to
ID
Both closer to

Mother (26)
Father ( 6)

Each closer to
FSS
Both closer to

Mother (23)
Father ( 7)

Each closer to
FOS
Both closer to

Mother (19)
Father ( 5)

Each closer to

same parent

different parent

same parent

different parent

same parent

different parent

same parent

different parent

In

24

11

32

30

10

24

11

 

94

Table 4.19.--Cell Means and Standard Deviations on the Variable of
Closeness to the Twin/Closest Sibling at the Present Time
by Twin-Type

 

Twin Background Questionnaire Item 21/Background Questionnaire Item 20:
"How would you rate your closeness to your twin/closest sibling at

the present time on the following scale? Put an "X" on the line below
that indicates how close you are."

 

Sgggp Mean §;2;
NT 4.91 1.29
ID 6.05 1.10
FSS 5.96 1.17
FOS 5.35 1.34

 

comparisons, revealed that non-twins rated themselves as being signifi-
cantly less closer to each other than did identical twins.

By sex and twin-type, female twins reported themselves as being
closer to each other than did male twins (Table 4.20), with the degree
of closeness ranging from about 5 to 6.5. A two-way analysis of
variance, followed by post hoc comparisons, showed that identical
females rated themselves as being significantly closer to each other
than did non-twin males, non-twin females, and fraternal opposite-
sex males.

On the basis of closeness, it seems as if there are three
distinct groups: the first includes non-twin males, non-twin females,
and fraternal opposite-sex males; the second includes fraternal same-
sex males, identical males, fraternal same-sex females, and fraternal

opposite-sex females; the third includes, in a class all by them-

selves, identical females.

95

Table 4.20.--Ce11 Means and Standard Deviations on the Variable of
Closeness to the Twin/Closest Sibling at the Present Time
by Twin-Type and Sex

 

Twin Background Questionnaire Item 21/Background Questionnaire Item 20:
"How would you rate your closeness to your twin/closest sibling at the
present time on the following scale? Put an "X” on the line below
that indicates how close you are."

great M922. :1)...
NT-Male 4.90 1.32
NT-Female 4.92 1.28
FOS-Male 4.93 1.45
FSS-Male 5.54 1.14
ID-Male 5.60 1.27
FSS-Female 5.66 1.24
FOS-Female 5.77 1.10
ID—Female 6.49 .69

 

Parental Emphasis of Similarities or Differences between Twins

 

It was reported in chapter two that parents of twins may emphasize
the similarities between their twins, which in turn encourages the
development of a unit identity. On the background questionnaire, the
twins were asked whether their parents had emphasized the similarities
or differences between the twins when they were young. About 50% of
the twins reported that their parents had not emphasized the similari-
ties or differences between them (Table 4.21). Excluding this
response, most twins stated that their parents had emphasized the

differences rather than the similarities between them and their twin.

96

Table 4.21.-—Frequency of Parental Emphasis of Similarities or
Differences between Twins by Twin-Type

 

Twin Background Questionnaire Item 13:
"When I was young, my parents (please check one of the following):
____Emphasized the similarities between me and my twin.
Emphasized the differences between me and my twin.
Neither of the above.
I don't recall."

 

m ass BE. 3211 (‘2)
Emphasized similarities 7 5 3 15 (12.5)
Emphasized differences 9 19 7 35 (29.2)
Neither of the above 22 13 24 59 (49.2)
Don't recall 2 3 6 11 ( 9.2)

 

Feelings about Being a Twin

 

In the last question asked of twins, they were asked to check
whether or not various statements concerning feelings of being a twin
applied to them when they were in elementary school. For the total
twin sample, the response checked most frequently, by 65% of the
sample (Table 4.22), was that they liked some things about being a
twin, but not others (response 5). The next three highest responses
that were checked reflected positive feelings about being a twin:

It was enjoyable to share things with the twin (response 7), the twin
was the best friend (response 8), and the twin relationship offered

a closeness not to be found in any other relationship (response 9).
Only 14% of the sample felt too competitive with the twin

(response 10), and less than 1% thought that being a twin was boring

or annoying (response 1).

97

Table 4.22.--Frequency of Feelings Concerning Being a Twin for the
Total Twin Sample

 

 

Twin Background Questionnaire Item 22:

"The following statements may or may not describe how you felt about
being a twin when you were in elementary school. Please put a check
in front of those statements which applied to the way you felt."

 

g (%)

l. I thought that being a twin was a real drag. 2 ( 0.2)
2. I got tired of the comparisons that were made

between my twin and me (for example, compari-

sons of physical characteristics, athletic

ability, or academic achievement). 58 (48.3)
3. I was indifferent to being a twin; it

didn't affect me one way or the other. 39 (32.5)
4. I felt that I had to do better or achieve

more than my twin. 32 (26-7)
5. I liked some things about being a twin,

but not others. 78 (65.0)
6. I resented sharing things with my twin

(for example, gifts, time, toys, friends,

and parents). 22 (18.3)
7. I liked sharing things with my twin. 67 (55.8)
8. My twin was my best friend; she/he

understood me most. 67 (55.8)
9. I enjoyed being a twin; it offered a close-

ness that could not be found in any other

relationship. 69 (57.5)
10. I felt too competitive with my twin. 17 (14.2)

11. I liked the competition between my twin
and me because it encouraged both of us
to do well. 34 (28.3)

 

98

Turning to the responses to these same questions by twin-type,
it was found that the ambivalence (response 5) about being a twin was
comparable between the groups (Table 4.23). This was the most fre-
quently checked response by the fraternal opposite-sex twins, while
fraternal same-sex twins most frequently checked that they got tired
of the comparisons that were made between them and their twin
(response 2). For identical twins, the most frequently checked
response was that the twin was the best friend and the one who under-
stood them the most (response 8).

More than half of the identical twins stated that they enjoyed
being a twin (response 9), but they also stated that they got tired of
the comparisons made between them and their twin (response 2). They
stated less frequently than the other two groups that they felt that
they had to do better or achieve more than their twin (response 4),
and that they found their relationship with their twin too competitive
(response 10). In fact, identical twins responded more frequently than
did the other two groups that they enjoyed the competition with their
twin because it encouraged both of them to do well (response 11).

Fraternal same-sex twins, in addition to stating that they tired
of the comparisons, also stated more frequently than the other two
groups that they felt that they had to do better or achieve more than
their twin (response 4), and that they felt too competitive with their
twin (response 10). On the other hand, however, about half of them
liked sharing things with their twin (response 7), and enjoyed being
a twin (response 9).

About half of the fraternal opposite-sex twins stated that they

were indifferent to being a twin (response 3), that they liked sharing

Table 4.23.--Frequency of Feelings Concerning Being a Twin by

99

Twin-Type

 

Twin Background Questionnaire Item 22:
"The following statements may or may not describe how you felt about
Please put a check

being a twin when you were in elementary school.
in front of those statements which applied to the way you felt."

10.

11.

I thought that being a twin was a
real drag.

I got tired of the comparisons that were

made between my twin and me (for
example, comparisons of physical
characteristics, athletic ability, or
academic achievement).

I was indifferent to being a twin; it
didn't affect me one way or the other.

I felt that I had to do better or
achieve more than my twin.

I liked some things about being a twin,
but not others.

I resented sharing things with my twin
(for example, gifts, time, toys,
friends, and parents).

I liked sharing things with my twin.

My twin was my best friend: she/he
understood me most.

I enjoyed being a twin; it offered a
closeness that could not be found in
any other relationship.

I felt too competitive with my twin.
I liked the competition between my

twin and me because it encouraged both
of us to do well.

ID

21

13

30

21

32

25

15

FSS

27

13

26

26

24

25

11

13

PCS

10

19

ll

22

20

ll

19

 

100
things with their twin (response 7), and that they enjoyed being a
twin (response 9). Compared to other groups, they stated less fre-
quently that their twin was their best friend (response 8) and that

they liked the competition with their twin (response 11).

Summary

In this study of separation-individuation, the comparisons
between (a) identical and fraternal twin mean scores on the five sub-
scales of the separation-individuation instrument, and (b) fraternal
same-sex and fraternal opposite-sex twin mean scores on the five sub-
scales of the separation-individuation instrument, were not signifi-
cant. However, comparisons between non-twin and twin mean scores on
the five subscales revealed a significant difference on the
Individuation II-Present subscale, indicating a difference between
twins and non-twins in the areas of dependency, jealousy, and guilt.
On the other four subscales, there were no significant differences.

The additional results provided some substantiation for the
validity of the separation-individuation instrument used in this
study. The mean scores on the Individuation I-Past, Individuation II-
Present, and Body Image subscales were significantly different between
those who reported being afraid to go to school as a child as com-
pared to those who did not report being afraid to go to school as a
child. In addition, mean scores on the Individuation I-Past subscale
were significantly different between those who reported missing school
an average amount or more often than most children as compared to those
who reported missing school less often than most children.

The mean rating of closeness with the twin or closest sibling was

in the order of, from high to low, identical twins, fraternal same-sex

101

twins, fraternal opposite-sex twins, and non-twins. Female twins
rated themselves as being closer than male twins. An analysis of
variance with post hoc comparisons revealed that non-twins, both male
and female, and fraternal opposite-sex males, were significantly less
close than identical female twins.

These and other findings of this study will be explored in more

detail in the discussion which follows in the next chapter.

CHAPTER V

SUMMARY AND CONCLUSIONS

In this chapter, the study on separation-individuation in twins is
summarized, and there is a discussion of the theory in relationship to
the findings, including an examination of the limitations of the study.
Finally, the implications for future research, and the implications of

the findings for counseling practice are explored.

Summary

The purpose of this study was to assess separation-individuation
between twins and non-twins, and to validate a revised objective measure
of separation-individuation. It was postulated that significant
differences between twins and non-twins, and between differing twin-
types, would provide evidence for the validity of the test itself, and
enlarge the field of knowledge concerning adult twins.

The sample in this study included 40 non-twins, 40 identical twins,
4O fraternal same-sex twins, and 40 fraternal opposite-sex twins. All
of the participants in this study were volunteers, college students, and
between the ages of 18 and 25. Each completed the separation-
individuation instrument and a background questionnaire. The separation-
individuation instrument consisted of five subscales, which had been
derived from a previous administration of the instrument to 211 college-

age students. The measure of internal consistency for each subscale, or

102

103

standard score alpha coefficients, was as follows:

Individuation I-Past .75
Individuation II-Present .84
Father .83
Family Rivalry .72
Body Image .74

The data were analyzed with a p-ratio of planned orthogonal
comparisons, with the probability of significance set at the .05 level.
A summary of the results is provided in Table 5.1. Analyses of variance
of comparisons based on (a) those who were afraid to go to school as
a child, as compared to those who were not, and (b) those who were
absent from school an average amount or more often than most children,
as compared to those who were absent less often than most children, pro-
vided some support for the validity of three of the five subscales,
including Individuation I-Past, Individuation II-Present, and Body Image.
Further analyses of the data revealed that separation-individuation was
not related to (a) residence with the twin, (b) attendance at the same
school with the twin, (c) parental emphasis of the similarities or
differences between the twins, (d) alliterative names, (e) a secret
language between the twins, (f) rated closeness to the twin, or
(g) dressing alike in elementary or high school. However, comparison of
those who dressed alike currently to those who never dressed alike
currently revealed a significant difference on the Individuation I-Past

subscale.

Discussion

 

The discussion which follows will be centered around three major

areas involved in this study. Included are the theory on which the

104

Table 5.l.--Summary of Significant Findings

 

Comparison Subscale Significance Level

 

Twins v. Non-Twins

Past N.S.
Present p < .05
Father N.S.
Rivalry N.S.
Body Image N.S.
Identicals v. Fraternals
Past N.S.
Present N.S.
Father N.S.
Rivalry N.S.
Body Image N.S.
Fraternal Same-Sex v.
Fraternal Opposite—Sex
Past N.S.
Present N.S.
Father N.S.
Rivalry N.S.

Body Image N.S.

 

105

study was based, the sample utilized in this study, the instrument
used to assess separation-individuation, and the limitations of each.

As previously stated in the review of the literature, most of the
conclusions regarding the intertwin relationship, and the separation-
individuation process as it relates to twins, are based on twins who
are in psychotherapy or undergoing psychoanalysis. While most of
these researchers utilized adult twins, thus making their findings
germane to this study, they utilized twins who were not necessarily
representative of twins in general. On the other hand, those researchers
who utilized "normal twins" in their studies had as their primary
samples, with the exception of Husén's (1959) study in Sweden, young
twins. Thus, a relative gap was left in the material available on
"normal" adult twins, which was one of the reasons this study was under-
taken.

On the whole, the authors of the case—study material concluded
that the twin relationship was unique because of the presence, from
birth, of another individual in the same developmental phase. This
factor alone, at least theoretically, can lead to separation-
individuation problems in twins, because of the necessity of not only
separating and individuating from the mother (which all children must do
for successful and normal development), but from the twin as well.

In the review of the material concerning parental reactions to
twins, it was found that parents tended to emphasize the similarities
between the twins, and that frequent splitting of the parents occurred,
in which one twin appropriated the mother, and the other the father.
However, in this study, about 50% of the twins stated that their parents

did not emphasize either the similarities or the differences between

106
them and their twin. The next most frequent response, given by about
30% of the sample, was that the parents emphasized the differences
between them and their twin, and only 12% stated that their parents
emphasized the similarities. Concerning the issue of the splitting of
the parents, three-quarters of the twin sample reported that they were
both closer to the same parent, usually the mother. Furthermore, the
responses of the non-twins resembled those of twins quite strongly, with
the exception of identical twins, who reported a somewhat lower inci-
dence of the splitting of the parents, as compared to the rest of the
sample. Both the parental emphasis of similarities and the splitting
of the parents are thought to contribute to separation-individuation
problems, and that both occurred with relatively low frequency in this
study may have contributed to the lack of significant differences, for
the most part, between twins and non-twins, and among twins.

In the review of the material concerning the intertwin relation-
ship, it was stated that dressing twins alike could also contribute to
the difficulties in separation-individuation. While most identical and
fraternal same-sex twins dressed alike in elementary school (most
fraternal opposite-sex twins did not), by the time they reached high
school, the majority of them did not. As a matter of fact, at the time
the study was conducted, a slightly higher percentage of non-twins were
dressing like their closest sibling, as compared to the percentage of
twins who were dressing like each other. This, again, may have con-
tributed to the finding of insignificant differences between the groups.

On the other hand, there were some notable differences between
twins and non-twins in this study. About 58% of the twins in this

study had alliterative names; this figure is somewhat higher than that

107

reported by Scheinfeld (1967) in his informal survey of twins. Also,
about 60% of the identical twins, 28% of the fraternal same-sex twins,
and 12% of the fraternal opposite-sex twins reported having a secret
language between them and their twin when they were young. While
Lézine (1951), Leonard (1961), and Zazzo (1978) have commented on the
potential detrimental consequences of alliterative names and a secret
language, as they may contribute to identity confusion and lack of
separateness, it appears as if the twins in this study may have over-
come these detrimental effects as they matured. A rather select sample
was used in this study, i.e., all participants were college students,
and perhaps this group of twins was able to overcome any handicaps
associated with these variables. Perhaps study of twins with less
educational background would reveal that this is not always the case.
An examination of the ratings of closeness between the twins, and
of the non-twins to their closest sibling, revealed that most, on the
average, saw themselves as being more than moderately close. There was
a distinct pattern, as was found by Koch (1966), Shields (1954), and
von Bracken (1934), with twins being closer than non-twins, and among
the twins, identicals rated themselves as being closer than fraternal
same-sex twins, who in turn rated themselves as being closer than
fraternal opposite-sex twins. The female twins rated themselves as
being closer to their co-twin than did male twins. However, the
separation-individuation subscale scores were not significantly
different from each other by twin rating of closeness. Perhaps the
measure of closeness was too crude; a rating of closeness determined
by more than one response may have been more appropriate and sensitive

to differences that existed.

108

In an attempt to explore the rivalry, competition, and ambivalence
that seem inherent in the twin relationship (Arlow, 1960; Joseph &
Tabor, 1961), the twin sample was queried as to their feelings about
being a twin when they were young. The most frequently checked response
was, "I liked some things about being a twin, but not others." While,
in hindsight, the researcher realizes that more specificity would have
been desirable in the phrasing of this question, responding to this
question does indicate some ambivalence about being a twin. Overall,
however, there seemed to be more frequent responses to the positive
items than to the negative ones. More than half of the respondents
indicated that their twin was their best friend, and that being a twin
offered a closeness that could not be found in any other relationship.

The responses to the items did vary by twin-type, and it was
found that fraternal same-sex twins were more competitive with their
twin than were identicals, as was found by Koch (1966), Husén (1959),
and von Bracken (1934). Fraternal same-sex twins checked, more fre-
quently than identicals, that they (a) got tired of the comparisons
that were made between them and their twin, (b) felt they had to
achieve more than their twin, and (c) felt too competitive with their
twin. Overall, as judged by responses to these eleven statements con-
cerning feelings about being a twin, the fraternal same-sex twins
generally reported more negative feelings about being a twin, the
identicals reported more positive feelings about being a twin, and the
fraternal opposite-sex twins reported general indifference to being
a twin. It is interesting that despite the more frequent response of
fraternal same-sex twins to the negative feelings, they still rate

themselves as being closer to each other than fraternal opposite-sex

109

twins, and almost as close as identical twins. Perhaps the passage of
time accounts for these changes; they were asked about their feelings
that they had as youngsters, but were asked to rate their closeness to
their twin at the current time.

Overall, there seems to be some discrepancy between the case study
material as gathered from past researchers, and the researcher's
material on twins as gathered in this study. The theory on which
separation-individuation in twins and the intertwin relationship is
based seems to come from a pool of subjects who have multiple problems;
parents initially had difficulty distinguishing one twin from the
other, and encouraged the similarities between the twins, giving them
alliterative names and dressing them alike. Between the twins, there is
much rivalry and competition, feelings of being one-half of a whole,
and an inability to separate from the twin. However, the parents of
the twins used in this study apparently emphasized the differences
rather than the similarities between the twins when they were young;
most of the twins do not dress alike currently, although they did when
they were younger; and most are not living with the twin or attending
the same school as the twin. In brief, the twin sample used in this
study appears to suffer from the lack of complicating and diverse
psychological difficulties that were evidenced by the individuals
discussed in the literature review.

Naturally, the question must be raised as to why this sample
failed to be useful in substantiating the theory of separation-
individuation in twins. First, this was a homogeneous sample of
college students 18 to 25 years old who were attending a large Mid-

western university. The twin sample consisted, then, of people who

110

probably would not have the range of problems that might be found in a
more heterogeneous sample. The twin sample consisted entirely of
volunteers; thus only those who had some interest in being a twin, or of
helping a twin (the researcher stated in the advertisements that she was
a twin doing research on twins) would probably be inclined to partici—
pate. (The researcher did obtain about 20% of the subjects used in this
study from twins who knew other twins, or from people in the dormitories
who knew of twins in residence halls throughout campus. These people
were contacted by phone, but they were still volunteers in the study.)
While the researcher does not regret, because of both time and financial
considerations, conducting the study in this manner, a more representa-
tive and random sample could have been obtained by, for instance,
obtaining a directory of members in twin organizations, and randomly
selecting a cross-section of twins to participate in the study. How-
ever, this would have been a biased sample, too, in that it would include
only those twins in such organizations, and again would probably include
only twins who had some special interest in their status as a twin.

The non-twin sample was obtained from classes being conducted
at Michigan State University during Spring Term, 1980, so this sample
did not consist of volunteers. Thus, the twins were volunteers, and
the non-twins were taken from classes; it is not known what effect
this had on the study, but there do not appear to be any substantial
or noticeable differences between the two samples.

The last issue to be discussed includes the instruments used in
this study, their validity, and their sensitivity in detecting
differences between the groups studied. The separation-individuation

instrument subscales were derived from a clustering of the items based

111

on the responses of 211 college students. Because school phobia is
one of the initial indicators of separation-individuation problems,
items which discriminated between those who were afraid to go to
school and those who were not afraid to go to school were retained.
Those items which failed to discriminate between these groups were
discarded; items which failed to discriminate between individuals were
discarded (for example, if an item was answered by almost the entire
sample as "completely true" or "completely false"); and items which
did not cluster with any of the other items were eliminated. Thus,
the subscales were constructed with a marked reliance on school
phobia as an indicator of separation-individuation difficulties.

In this study, three of the five subscales were able to detect
differences between school phobic individuals, but generally, the
instrument was not sensitive enough to detect differences between
twins and non-twins, if in fact these differences exist. The only
exception to this finding was that it was able to detect a difference
between twins and non-twins on the Individuation I-Present subscale.
Currently, then, twins appear to have slightly more difficulty than
non-twins in the areas of rejection, attachment, and jealousy.

Overall, however, the study did not help to validate the instru-
ment to the extent that had been anticipated. It may be an instrument
designed to assess separation-individuation problems as it relates to
only one indicator, school phobia. It may be that it is not sensitive
enough to be able to discriminate between twins and non-twins, or
that there are no differences between twins and non-twins. Certainly,
additional administrations of the instrument to other groups, including

twins, would be helpful in clarifying those issues.

112

Concerning the background questionnaire, it was unfortunately
necessary to limit it in length, although there were more questions
concerning the twin relationship left unanswered than answered. It
was useful in that it did provide information about behaviors or
attitudes among adult twins as compared to non-twins, and uncovered
some of the similarities and differences between the two groups.
Many of the twins stated that they found the Twin Background
Questionnaire to be quite interesting, as it prompted them to think
about being a twin and their reactions to it. It was limited, how-
ever, because only rough estimates could be made of any of the
characteristics of the twin relationship; the depth or any nuances of
the relationship were not addressed.

A factor which no doubt affected the results of the entire study
was that all of the information obtained was based on self-report,
with no outside criteria to evaluate the validity of any of the
responses. Even though the responses to all questionnaires were
anonymous, social desirability of response was probably a factor in
this study. Many of the questions concerned past events, and there
may have been some forgetting about what happened or how respondents
felt when they were younger. Despite the fact that the instruments
used were "objective" pencil and paper ones, there is still a high
degree of subjectivity involved in this study. As a simple example,
most of the twins reported that they had alliterative names, but
most also stated that their parents, if they stressed either simi-
larities or differences between the twins, stressed the differences,
not the similarities. However, most of the twins dressed alike in

elementary school. Parental stress on differences, yet encouraging

113

like dress, appears to be a contradiction. Further elaboration on
the questions asked appears to be necessary.

In summary, this researcher suggests not that the theory is
necessarily wrong (certainly there are twins who do have difficulties
in the separation-individuation process), but that perhaps generaliza-
tions have been over-extended to include most twins, when such may not
be the case. In the interpretation of the findings, there is the
possibility that Leonard (1961) suggests, i.e., that the identity
3 deux substitutes for an individual identity, and that this unit
identity may be masking any separation-individuation problems that
exist in this twin sample. However, it is the researcher's opinion
that the findings relate in a more consistent manner to Joseph's
(1961) comment.

Further analytic research with more apparently healthy

and successful twin individuals may reveal the useful

adaptations that can come out of the circumstances of

being a twin, rather than maintain the (unfortunate)

emphasis on special problems and pathology that arise from

the investigation of psychopathological material only.

(p. 166)

This study was undertaken as a step in this direction.

The sample used was a non-random, non-representative homogeneous
group of twins who were college students between the ages of 18 and 25.
In many instances, they did not appear to have the problems in
separation-individuation that were cited by the researchers on the
intertwin relationship. With the exception of the difference found
between twins and non-twins on the Individuation I-Present subscale,
no differences were found between twins and non-twins, between identicals

and fraternals, or between fraternal same-sex and fraternal opposite-

sex twins. This result may have occurred because the instruments used

114

were not sensitive enough to detect the differences, if in fact they
do exist. Specific recommendations and implications for further
research are considered in the next section to improve upon research

in this area.

Implications for Further Research

 

Based on a consideration of the limitations of this study, and
an analysis of its strengths and weaknesses, there are a number of
recommendations that can be made to improve upon research in this
area. Perhaps the first and most important recommendation is that
more needs to be known about separation-individuation in normal twins,
both as youngsters and as adults. Too many of the conclusions regard-
ing not just separation-individuation, but many psychodynamics, are
based on the study of a small and limited number of case studies, or
on samples which include people who are having some degree of diffi-
culty in coping with their current life situation. This is certainly
the case with twins. Most researchers have focused on the negative
aspects of the twin relationship, very few on the positive aspects.
Some twins may not have participated in this study, and perhaps would
not in other studies, because of this bias in the literature on twins.

Part of the investigation of separation-individuation in normal
twins should include a comparison of these individuals with non-twins.
The perceived "uniqueness" of the twin relationship may be the result
of only looking at the twin relationship and a lack of consideration
of the fact that twinning can occur in non-twins as well as in twins.
Koch (1966) was one of the few researchers who included non-twins in her
study on twins, and while she did find that twins were closer than

non-twins, she did not find that twins, as compared to non—twins, had

115

more problems. It does not seem that it would be that difficult to
obtain a sample of non-twins to use as a comparison or a control group.
It is also recommended that future research on twins be broadened to
include a random, representative group of twins. The use of a homo-
geneous group makes it difficult to detect differences, and a more
heterogeneous group would perhaps enable researchers to find any
differences that might exist.

In addition to the above recommendations, the instrument used to
assess separation-individuation requires further exploration. This was
only the third time that it was used. Further use and refinement of the
subscales would improve both their reliability and item content. In
particular, both the Family Rivalry and Father subscale appear to need
revisions. It is not known whether this is an instrument that is use-
ful to assess only one aspect of separation-individuation, i.e.,
school phobia, or if it is useful to assess the entire process. Thus,
more studies of the validity of this instrument, which incorporate
external criteria for evaluating separation-individuation, are needed.

Further refinement of instruments used to acquire specific informa-
tion about the twin relationship is also needed. The items used on the
background questionnaires in this study could only provide a rough
indication of how close twins were to each other, or how they felt
about being a twin. A longer questionnaire, while it would require more
time to complete, would also provide more information about the inter-
twin relationship.

In sum, the researcher believes that more research on separation-
individuation in twins and non-twins would be appropriate. With further

revision of instruments, and with the use of random and representative

116

samples, more would be known about separation—individuation in both

groups, and whether the twin relationship is indeed unique.

Implications for Counseling and Counseling Practice

 

Despite the fact that few significant differences between twins
and non-twins were found in this study, some twins seem to have
difficulty in the separation-individuation process as it relates to the
twin. Counselors might well help twins to clarify their feelings about
their twin, to dissolve the twin symbiosis, and to establish their own
identity. The latter may be particularly difficult because to "be a
person in your own right" may mean only one thing, i.e., to be without
the twin.

In the treatment of twins, it is important for counselors to be
aware of cultural stereotypes. Some counselors may have, just as other
people do, a particular stereotype of what twins and the twin relation-
ship is like. The twins in this study, for the most part, stated that
they did not like having people think of them as being a unit, and that
people were, in general, insensitive to twins and their particular needs.
For example, one identical female stated, "Parents and teachers thought
we should be alike in gyg£y_way. They didn't look upon us as individuals
and having individual interests." Fraternal same-sex twins in particular
stated that they didn't like the comparisons that were made between
them and their twin as to who was the smarter, the taller, the older,
the heavier, or the more social. A female fraternal same-sex twin said,
"We both resented the black and white contrasts of our personalities--
my twin was always the 'emotional' one, and I was forced to play the part

of the 'rational' shy twin." It is important for counselors to be

117

aware of these issues, and to not treat twins, as some do, as objects
of curiosity, or as individuals who are a unit.

Another issue in the treatment of twins concerns Steele's
(unpublished, cited by Joseph, 1961) comment that the counseling rela-

tionship is a situation par excellence for recreating the twinship. In

 

some twins, there is a need to recreate the twinship with friends,
spouses, and even counselors. Problems in terminating the therapy may
result because of the desire, on the part of the twin, for perpetual
treatment with the "twin-therapist."

Coupled with this need to recreate the twinship with the counselor
is the problem of twins wanting to see the same counselor at the same
time. For example, it is not infrequent for one twin to seek therapy,
only to have the other twin immediately follow this step. As Joseph &
Tabor (1961) and Burlingham (1963) found, the feeling is, ”If my twin
needs therapy, I must need it too." If the goal of therapy is to
assist each twin in developing a separate identity, it would be unwise
for both to share the therapy hour, or the same therapist.

The implications of this study for counselors and the counseling
practice need not be restricted to twins themselves. As was noted in
the discussion of the intertwin relationship, the phenomenon of twinning
can occur in people who are not twins, e.g., between siblings, close
friends, or husbands and wives. As an example, a non-twin, after seeing
the newspaper advertisement, called the researcher and was insistent
about participating in this study because, she said, she and her cousin
had been raised as, and were just like, twins.

However, important as the twinship is in personality development,

counselors would be well advised to recall Hartmann's (1934-35/1964)

118

warning against attributing too much to it. Not all problems result
from the twinship itself. This study gives the preliminary, and perhaps
accurate, impression that twins show as much variation in handling the

separation-individuation process as do single individuals.

In Retrospect

 

In retrospect, although for the most part the null hypotheses
in this study could not be rejected, it appears to be premature to state
that there are no differences between separation-individuation in twins
and non—twins. For the most part, no significant differences were found
between non-twins and twins, nor between the different twin-types, but
the null hypotheses can only "not be rejected," not "accepted." Thus,
there may be some differences between the non-twin and twin separation-
individuation process that were not detected in this study. There are
many issues which are unresolved; there is a wealth of information stat-
ing that twins have a "unique" relationship, and some information which
finds few differences between twins and non-twins, with the exception
of closeness between twins and non-twins.

Based on the review of the literature, there seems to be a void
in the knowledge concerning the connection between early separation-
individuation in twins, and how adult twins cope with and adapt to inter-
personal relationships involving attachment and separation. Given the
view of many researchers, and some twins used in this study, that the
twin relationship is one of the closest relationships that exist between
two people, it could serve as a paradigm for investigating the

separation-individuation process throughout the life cycle.

APPENDICES

APPENDIX A

POSTED SIGN TO RECRUIT TWINS
FOR THE STUDY

TWINS

I AM A TWIN WHO IS DOING RESEARCH ON TWINS, AND I NEED

YOU

WHETHER YOU ARE IDENTICAL OR FRATERNAL, MALE OR FEMALE.

IF YOUR TWIN IS NOT IN TOWN, DON'T WORRY AS I DON'T HAVE

TO HAVE TWIN PAIRS. CALL JILL AT 353-3726 OR 332-2912.

TWINS

119

APPENDIX B

NEWSPAPER ADVERTISEMENTS TO RECRUIT TWINS FOR THE STUDY

This advertisement appeared in the State News on April 29, 1980, p. 5.

 

I am a twin who is doing research on the
Psychology of Twins, and I need ‘

YOU

Whether you are fraternal or Identical, male or
female (if your twin is not in town, don't
worry as I don't have to have pairs.) Please
call Jill at 353-3726 or 33229] 2.

 

 

 

This advertisement appeared in the State News on May 8, 1980, p. 2.

Twins

I am a twin who is doing research
on the psychology of twins, and I
need

You

Whether you are fraternal or identical, male

or female (if your twin is not in town,

don't worry as I don't have to have pairs.)

Please call Jill at 353-3726 or 332-2912.
Male Min: —I need you, too!

 

120

APPENDIX C

SEPARATION-INDIVIDUATION INSTRUMENT, FORM A

PLEASE NOTE:

Copyrighted materials in this document
have not been filmed at the request of
the author. They are available for
consultation, however, in the author's
university library.

These consist of pages:

lZl-l59

 

 

 

 

 

Universny'
Microfilms
International

300 N. ZEEB RD., ANN ARBORMI 481061.313} 761-4700

Please respond to the following statements as quickly and as accurately
as you can. Please do not omit any items. Read each statement, then
select one of the four responses listed below, according to whether you
think the statement is completely false, mostly false, mostly true, or
completely true.

If you were raised primarily by someone other than your mother-—for
example, by a stepmother, grandmother, older sister, or aunt--p1ease
answer the "mother" items with that person in mind. Do the same with
the "father" items.

Completely Mostly Mostly Completely
True True False False
l 2 3 4

1. In most situations there is no clear right or wrong.

2. When I was growing up I didn't know if my parents had sexual rela-
tions or not.

3. I am not a jealous person.

4. When I was a child I felt nervous about returning to school after
a vacation, even when I really wanted to go.

5. I am not very concerned with whether people like me or not.

6. If someone I care about very much is upset or hurt, I seem to feel
their pain almost as if it were my own.

7. When I was a child I didn't have to check everything with my
parents before I did it.

8. I have often felt that my father needed me as much as I needed
him.

9. My brother(s) or sister(s) and I fought quite often when we were
kids.

10. I have had older women friends or relatives who were like mothers
to me.

11. When I was a child I sucked my thumb.

12. When someone I like doesn't like me or want to be around me I try
and figure out why.

13. I used to wish I had a different father.
14. I can't bear the thought of failing at anything.

15. I think I was tied to my mother's apron strings.

121

122

Completely Mostly Mostly Completely
True True False False
l 2 3 4

16. My parents were so busy working and raising a family that they
didn't go out much on weekends.

17. My mother or father is my best friend.

18. I usually know when to quit.

19. I am neither too tall nor too short.

20. I feel guilty when I leave someone.

21. I don't hide very much about myself from others.

22. Neither I nor anyone in my family has asthma. (Answer either 1
or 4).

23. I am not sure of what I want to do with my life.
24. I hate to make mistakes, because I am so hard on myself when I do.
25. I don't feel guilty as often as most people do.
26. I don't think I should take care of other people.
27. I do not catch colds easily.

28. I have often felt that my mother needed me as much as I needed
her.

29. I'm slow to let people know how much I like them because I'm
afraid I'll come on too strong.

30. I am not a stubborn person.
31. I don't mind taking orders from my superiors.
32. I am afraid of my father.

33. My mother listens and doesn't get upset when I tell her my
problems.

34. As a child, I never felt uneasy about going to the movies.
35. People think I am just like my mother or my father.

36. The thought of committing suicide over failing at something does
not occur to me.

37. From the very first day of kindergarten I enjoyed school and
couldn't wait to go.

123

Completely Mostly Mostly Completely
True True False False
l 2 3 4

38. I usually express my anger or irritation when I feel it.
39. I am a capable person.

40. My parents encouraged me to bring along my brother or sister when
I went out with my friends. (If only child, leave blank)

41. I get frightened when one of my parents gets sick.
42. I am very close to my father.

43. Most people will not let you down.

44. I like the way my face and body look.

45. I always felt that my parents would be very unhappy if I moved
away from home when I grew up.

46. I have never been shy.

47. If I had to choose, I would rather be taken care of than take
care of others.

48. Some people think I am aggressive.

49. When people I am close to go away on a trip, I worry that some—
thing might happen to them.

50. My father likes to tell me what to do.

51. I never really give up, even when I should.

52. I like less physical affection than most people.

53. My mother was less critical of me than my father.

54. I eat when I feel upset.

55. As a child I was told more about sex than most children my age.
56. I think I am lovable.

57. My parents think it is awful if I get into a fight with my
brother(s) or sister(s). (If only child, leave blank)

58. I used to regularly have big fights with my mother.

59. My father's children are his life.

124

Completely Mostly Mostly Completely
True True False False
l 2 3 4

60. It doesn't really bother me when people refuse to admit they are
wrong.

61. I enjoy spending time in the house alone.

62. I feel scared when someone I am close to goes away.
63. I feel foolish when I cry.

64. As a child I was not absent from school very often.
65. My father is not overprotective towards me.

66. I am a talkative person.

67. I have never had trouble with my weight.

68. I enjoy sex more than most people.

69. I get attached to people easily.

70. My mother likes to tell me what to do.

71. When I am involved in a romantic relationship, I do not usually
think that my partner will cheat on me.

72. My father listens and doesn't get upset when I tell him my
problems.

73. I feel guilty when I think negative things about my mother.

74. I expeCt much more of people in authority than of people in
general.

75. I am a self-conscious person.

76. Most people do not take advantage of others.

77. When my parents raised me, they hardly ever yelled at me.
78. I can take care of myself in any situation.

79. My expectations for myself are tremendous.

80. When I was growing up, my father didn't mind if I wasn't home for
dinner.

81. You should take care of yourself more than other people.

125

Completely Mostly Mostly Completely
True True False False
1 2 3 4

82. When I was a child and got into arguments and fights, my parents
didn't get involved unless someone might get physically hurt.

83. I am afraid of my mother.
84. I want more affection from people than I have a right to expect.

85. I get jealous when I see a close friend of mine having a really
good time with someone else.

86. I am a calm and relaxed person.
87. I feel guilty when I think negative things about my father.
88. It is possible to feel both love and hate for the same person.

89. I threw tantrums when I was younger if I didn't get what I
wanted.

90. I have sometimes been homesick.

91. As a teenager I picked my own clothes.
92. I am not very critical of myself.

93. Eating usually makes me feel better.

94. I am never positive that I have done a good job until someone
else tells me that I have.

95. I get very frightened when I think that someday my parents will
die.

96. I used to regularly have big fights with my father.
97. I have never smoked a pipe, cigarettes, or cigar regularly.
98. I have an active social life.

99. I enjoy it when my friends and family are physically affectionate
towards me.

100. I am very close to my mother.

101. When I was younger I carried around a teddy bear, blanket, or
favorite toy.

102. I like my looks just the way they are.

126

Completely Mostly Mostly Completely
True True False False
l 2 3 4

103. Caring for others makes me feel good.
104. I am a quiet person.

105. I, or someone in my family, get migraine headaches.
(Answer 1 or 4)

106. I am often afraid that someone I care about very much will find
another person who they will like better than me.

107. My parents encouraged me to make my own decisions.
108. I was a late bloomer.
109. Ending a relationship is not particularly difficult for me.

110. I have had older men friends or relatives who were like fathers
to me.

111. I have said terrible things to my mother.
112. My mother is not overprotective towards me.

113. Sometimes I think I need more love than anyone could possibly
give me.

114. I used to wish I had a different mother.

115. I used to get an upset stomach before I left for school in the
morning.

116. I have not dated as often as I would have liked to.

117. When I was in elementary school one of my parents would want to
take me to school.

118. I like the idea of living alone.

119. I have said terrible things to my father.

120. I like my friends to be like me.

121. When someone rejects me I get very angry inside.

122. It doesn't bother me if someone close to me disagrees with me on
an important matter.

123. If I ever let out all the anger in me I might really damage
someone.

127

Completely Mostly Mostly Completely
True True False False
l 2 3 4

124. My mother has said that my father's relatives sometimes seem to
mean more to him than we do.

125. As a child in school, it was very important to me to please the
teacher and have him/her like me.

126. I do not hide the little kid in me.

127. I can take criticism without feeling hurt or upset.

128. I love to sing or whistle.

129. As a child I spent a lot of time with my parents.

130. People like to come to me with their problems.

131. I am neither too fat nor too thin.

132. No one will ever love me as much as members of my family do.
133. I am an independent person.

134. I, or someone in my family, have ulcers. (Answer either 1 or 4)
135. When I was very young I was afraid of strangers.

136. I rarely let people get close enough emotionally to hurt me.
137. I don't feel responsible for my mother's happiness.

138. When I was growing up, my mother didn't mind if I was not home
for dinner.

139. My family is not exceptionally close.

140. My mother's children are her life.

141. During some period in my life I was convinced I would die young.
142. I sometimes go on eating binges.

143. As a youngster, I did not take trips away from home by myself
very often, such as going away to camp.

APPENDIX D

SEPARATION-IDNVIDUATION INSTRUMENT, FORM B

Please respond to the following statements as quickly and as accurately
as you can. Please do not omit any items. Read each statement, then
select one of the four responses listed below, according to whether you
think the statement is completely true, mostly true, mostly false, or
completely false.

If you were raised primarily by someone other than your mother, for
example, by a stepmother, grandmother, older sister, or aunt, please
answer the "mother" items with that person in mind. Do the same with
the "father" items.

Completely Mostly Mostly Completely
True True False False
l 2 3 4
1. My father's children are his life.
2. When I get angry I feel like smashing things.
3. I'm not very concerned about pleasing other people.
4. During some period in my life I was convinced I would die young.
5. Generally, I would say that sex is over-rated.
6. I used to regularly have big fights with my mother.
7. My sex life is very satisfactory.
8. When I was growing up, my father didn't mind if I wasn't home for
dinner.
9. When I was a child I didn't have to check everything with my
parents before I did it.
10. I wish that my father would have supported me more often when I
disagreed with my mother.
11. I get very frightened when I think that someday my parents will
die.
12. I don't pay as much attention to my physical appearance as I
probably should.
13. I am not attracted to members of the opposite sex who are some-
what older than I am.
14. My mother always put her children's needs ahead of her own.
15. When I think about giving a party I worry that people won't come.
16. When I was very young I was afraid of strangers.

128

129

Completely Mostly Mostly Completely
True True False False
1 2 3 4

17. My father listens and doesn't get upset when I tell him my
problems.

18. I have said terrible things to my mother.

19. It takes me less time than most people to "loosen up" in a
social situation.

20. I am afraid of my mother.

21. When I was in elementary school one of my parents would want to
take me to school.

22. I think pets can provide companionship almost like people.
23. I am not too fat or too thin.

24. My mother has said that my father's relatives sometimes mean
more to him than we do.

25. I have never been shy.

26. I am never positive that I have done a good job until someone
else tells me that I have.

27. I think I was tied to my mother's apron strings.
28. I don't usually pull for the underdog.

29. I threw tantrums when I was younger if I didn't get what I
wanted.

30. I fill the gap in a conversation even when I don't feel like
talking.

31. I fear that I will be rejected by people I really care about if
I express hostility toward them.

32. Sometimes I just feel empty.

33. I am often afraid that someone I care about very much will find
another person who they will like better than me.

34. I am very close to my father.
35. I usually know when to quit.

36. I believe that expressing hostility does more harm than good.

130

Completely Mostly Mostly Completely
True True False False
l 2 3 4

37. I have sought out parent substitutes at some time in my life.
38. Most people will not let you down.
39. I am a capable person.

40. I used to get an upset stomach before I left for school in the
morning.

41. My father was not at home as much as my mother wanted him to be.
42. As a child I was not absent from school very often.

43. I get attached to people easily.

44. When I love someone, I feel that the person is a part of me.

45. I used to wish I had a different father.

46. I am a calm and relaxed person.

47. My mother liked most of our neighbors.

48. I am a self-conscious person.

49. I have a sweet-tooth.

50. I have often felt that my father needed me as much as I needed
him.

51. When I think about growing old I don't worry about being alone.
52. My motto is, "If you want something done right, do it yourself."

53. When I was a child I felt nervous about returning to school after
a vacation, even when I really wanted to go.

54. Sometimes I think I need more love than anyone could possibly
give me.

55. Adolescence was not a particularly difficult time for me.

56. If people I care about knew how I really felt about them some-
times, they would not like me.

57. My family is not exceptionally close.

58. My parents encouraged me to make my own decisions.

131

Completely Mostly Mostly Completely
True True False False
1 2 3 4

59. If I ever let out all the anger in me I might really damage
someone.

60. It is possible to feel both love and hate for the same person.
61. When someone rejects me I get very angry inside.

62. My father likes to tell me what to do.

63. I am not afraid of failing.

64. I feel guilty when I think negative things about my mother.
65. I am a talkative person.

66. No one will ever love me as much as members of my family do.
67. I like being held as much as I like sex.

68. My father is not overprotective towards me.

69. When people I am close to go away on a trip, I worry that some-
thing might happen to them.

70. I react strongly to being rejected, even by people that I don't
know very well.

71. The thought of committing suicide over failing at something does
not occur to me.

72. I used to regularly have big fights with my father.
73. I don't feel responsible for my mother's happiness.
74. I love to eat.

75. I have never been shy.

76. I am afraid of my father.

77. For most of my life I was an underachiever.

78. When someone is late for an appointment with me I immediately
think that they are not going to show up.

79. My father was deeply involved in the emotional life of our
family.

80. My mother is not overprotective towards me.

132

Completely Mostly Mostly Completely
True True False False
l 2 3 4

81. I feel scared when someone I am close to goes away.

82. It doesn't bother me if someone close to me disagrees with me on
an important matter.

83. I think I am sexy.

84. My parents never discouraged me from moving away from my home—
town .

85. I get jealous when I see a close friend of mine having a really
good time with someone else.

86. I have almost always worked up to my potential.

87. I like the way my face and body look.

88. I feel guilty when I think negative things about my father.
89. I don't depend on others too much for my happiness.

90. There was hardly any sibling rivalry in my family. (If only
child, leave blank)

91. I don't get angry when other people try to tell me what to do.
92. I am not prone to depression.

93. As a child I spent a lot of time with my parents.

94. My mother likes to tell me what to do.

95. I don't think I'm very attractive.

96. I feel guilty when I leave someone.

97. It's not hard for me to really let go.

98. I tend to overexplain things to people.

99. From the very first day of kindergarten I enjoyed school and
couldn't wait to go.

100. My father had no difficulty expressing his true feelings.

APPENDIX E

BACKGROUND QUESTIONNAIRE USED WITH
SEPARATION-INDIVIDUATION
INSTRUMENT, FORM B

BACKGROUND QUESTIONNAIRE

Please check the appropriate response to the following questions.
Numbers following responses are for coding purposes only, so you can
ignore them.

1.

10.

11.

Age 17—23 (1)
24-30 (2)
31-40 (3)
41-50 (4)
50 or over (5)

Sex Female (1)
Male (2)

Race Black (1)
White (2)
Other (3)

Marital status Single (1)
Married (2)
Separated (3)
Divorced (4)
Widowed (5)

Religious background Protestant (1)
Catholic (2)
Jewish (3)
Other (4)
I currently live at home with my parents Yes (1)

No (2)

There were times when I was afraid to go to school as a child

Yes (1)
No (2)
I have had or currently have asthma Yes (1)
No (2)
I get severe or migraine headaches Yes (1)
No (2)
I get more than two colds a year Yes (1)
No (2)

When I get upset the physical symptom I experience most often is
(check only one)

upset stomach (I) backaches (4)
diarrhea (2) constipation (5)
headaches (3) other (6)

 

133

12.

13.

14.

134

As a child I missed school less often than most children (1)
an average amount (2)
more often than most children (3)

My father owns his own business or worked in a business owned by

someone in our family Yes (1)
No (2)

My father is more than five years older than my mother Yes (1)
No (2)

APPENDIX F

CLUSTERS DERIVED FROM SEPARATION-INDIVIDUATION
INSTRUMENT, FORM B

Cluster 1, Individuation I-Past

2.
4.

11.

16.

21.

25.
38.

40.

42.
47.

53.

55.

59.

77.

99.

When I get angry I feel like smashing things.

During some period in my life I was convinced I would die young.
I get very frightened when I think that someday my parents will
die.

When I was very young I was afraid of strangers.

When I was in elementary school one of my parents would want to
take me to school.

I have never been shy.*

Most people will not let you down.*

I used to get an upset stomach before I left for school in the
morning.

As a child I was not absent from school very often.*

My mother liked most of our neighbors.*

When I was a child I felt nervous about returning to school
after a vacation, even when I really wanted to go.

Adolescence was not a particularly difficult time for me.*

If I ever let out all the anger in me I might really damage
someone.

For most of my life I was an underachiever.

From the very first day of kindergarten I enjoyed school and

couldn't wait to go.*

 

*Item is reflected (reverse-scored).

135

136

Cluster 2, Individuation II-Present Status

 

3.

26.

31.

32.

33.

43.
48.
51.

54.

61.
63.
64.

70.
73.
81.

82.

85.

I'm not very concerned about pleasing other people.*

I am never positive that I have done a good job until someone
else tells me that I have.

I fear that I will be rejected by people I really care about if
I express hostility toward them.

Sometimes I just feel empty.

I am often afraid that someone I care about very much will find
another person who they will like better than me.

I get attached to people easily.

I am a self-conscious person.

When I think about growing old I don't worry about being alone.*
Sometimes I think I need more love than anyone could possibly
give me.

When someone rejects me I get very angry inside.

I am not afraid of failing.*

I feel guilty when I think negative things about my mother.

I react strongly to being rejected, even by people that I don't
know very well.

I don't feel responsible for my mother's happiness.*

I feel scared when someone I came close to goes away.

It doesn't bother me if someone close to me disagrees with me on
an important matter.*

I get jealous when I see a close friend of mine having a really

good time with someone else.

 

*Item is reflected (reverse-scored).

137

89. I don't depend on others too much for my happiness.
96. I feel guilty when I leave someone.

98. I tend to overexplain things to peOple.

138

Cluster 3,¥Father

1.

17.

34.
45.

50.

57.

76.

79.

93.

My father's children are his life.*

My father listens and doesn't get upset when I tell him my
problems.*

I am very close to my father.*

I used to wish I had a different father.

I have often felt that my father needed me as much as I needed
him.*

My family is not exceptionally close.

I am afraid of my father.

My father was deeply involved in the emotional life of our
family.*

As a child I spent a lot of time with my parents.*

 

*Item is reflected (reverse-scored).

139

Cluster 4, Family Rivalry

 

6. I used to regularly have big fights with my mother.

10. I wish that my father would have supported me more often when I
disagreed with my mother.

18. I have said terrible things to my mother.

20. I am afraid of my mother.

29. I threw tantrums when I was younger if I didn't get what I
wanted.

46. I am a calm and relaxed person.*

60. It is possible to feel both love and hate for the same person.

84. My parents never discouraged me from moving away from my hometown.*

90. There was hardly any sibling rivalry in my family. (If only

child, leave blank.)*

 

*Item is reflected (reverse-scored).

140

Cluster 5, Bodinmage

7. My sex life is very satisfactory.*

12. I don't pay as much attention to my physical appearance as I
probably should.

23. I am not too fat or too thin.*

66. No one will ever love me as much as members of my family do.

83. I think I am sexy.*

87. I like the way my face and body look.*

95. I don't think I'm very attractive.

 

*Item is reflected (reverse-scored).

APPENDIX G

STANDARD SCORE COEFFICIENT ALPHAS AND COMMUNALITIES IN THE
DIAGONAL FOR THE FIVE CLUSTERS

Communality in the Diagonal,f§lusters 1-5

 

For ease of presentation, Cluster 1 = Individuation I-Past
Cluster 2 = Individuation II—Present Status
Cluster 3 = Father
Cluster 4 = Family Rivalry
Cluster 5 = Body Image

1 .2. a f: ,5.

.1 100 62 44 66 25

.2 100 30 58 32

_3 100 43 15

fi_ 100 20

§_ 100

Standard Score Coefficient Alphas, Clusters 1-5

 

 

Cluster Coefficient Alpha
1 .75
2 .84
3 .83
4 .72
5 .74

141

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ma

ma
ma

OH

OH
NH

mm

NH
OH

oa
ma
ma

OH

ma
NN

om

 

MM

mm

mu

mm

mm

mm

mm

mm

4m

mm

aw

NN _mm

wN mN mm

ON NH mN Mm

ON NN mN NN mm

sN NN mN on mN mm

NH ON on mm NH NN mm

NH mN on NN sN as mm mm

«N NH NN NN NN mm mm mm mm

on Nm os as mm on ma as am WM
mm mm mm mm mm. mm mm mm aw

N pmumsau .Hmaowmfiu era a“ Nuflama38500

Communality in the diagonal,

34

67

79

55

4O

57

53

45

39

144

45

51

‘33

35

38

50

57

45

39

31

38

Cluster 3

17

51

32

37

34

34

36

38

30

37

39

30

34

29

4O

4O

24

29

40

28

26

24

29

21

27

41

18

36

26

ll

18

Communality in the diagonal,

_Q

41

18

62

39

10

4O

35

34

145

20

32

22

38

25

9O

——

25

28

21

22

24

Cluster 4

29

24

29

15

18

14

ll

l9

19

23

26

12

14

19

16

28

l9

17

12

25

13

18

15

19

16

28

18

ll

Communality in the diagonal,

95

58

87

55

56

23

37

50

35

146

83

___—___

53

42

36

32

12

35

39

28

3O

25

Cluster 5

32

35

25

21

16

18

14

l6

l4

APPENDIX H

SEPARATION-INDIVIDUATION INSTRUMENT, FORM C

Please respond to the following statements as quickly and as accu-
rately as you can. Please do not omit any items. Read each statement,
then select one of the four responses listed below, according to
whether you think the statement is completely true, mostly true,
mostly false, or completely false.

If you were raised primarily by someone other than your mother, for
example, by a stepmother, grandmother, older sister, or aunt, please
answer the "mother" items with that person in mind. Do the same with
the "father" items.

Completely Mostly Mostly Completely
True True False False
1 2 3 4

1. My father's children are his life.

2. When I get angry I feel like smashing things.

3. I'm not very concerned about pleasing other people.

4. During some period in my life I was convinced I would die young.

5. Generally, I would say that sex is over-rated.

6. I used to regularly have big fights with my mother.

7. My sex life is very satisfactory.

8. When I was growing up, my father didn't mind if I wasn't home
for dinner.

9. When I was a child I didn't have to check everything with my
parents before I did it.

10. I wish that my father had supported me more often when I dis-
agreed with my mother.

11. I get very frightened when I think that someday my parents will
die.

12. I don't pay as much attention to my physical appearance as I
probably should.

13. I am not attracted to members of the opposite sex who are some-

what older than I am.

147

148

Completely Mostly Mostly Completely
True True False False
1 2 3 4

14. My mother always put her children's needs ahead of her own.

15. When I think about giving a party I worry that people won't come.

16. When I was very young I was afraid of strangers.

17. My father listens and doesn't get upset when I tell him my
problems.

18. I have said terrible things to my mother.

19. It takes me less time than most people to "loosen up" in a
social situation.

20. I am afraid of my mother.

21. When I was in elementary school one of my parents would want to
take me to school.

22. I think pets can provide companionship almost like people.

23. I am not too fat or too thin.

24. My mother has said that my father's relatives sometimes mean
more to him than we do.

25. I have never been shy.

26. I am never positive that I have done a good job until someone
else tells me that I have.

27. I think I was tied to my mother's apron strings.

28. I don't usually pull for the underdog.

29. I threw tantrums when I was younger if I didn't get what I wanted.

30. I fill the gap in a conversation even when I don't feel like
talking.

31. I fear that I will be rejected by people I really care about if

I express hostility toward them.

149

Completely Mostly Mostly Completely
True True False False

1 2 3 4

32. Sometimes I just feel empty.

33. I am often afraid that someone I care about very much will find
another person whom they will like better than me.

34. I am very close to my father.

35. I usually know when to quit.

36. I believe that expressing hostility does more harm than good.

37. I have sought out parent substitutes at some time in my life.

38. Most people will not let you down.

39. I am a capable person.

40. I used to get an upset stomach before I left for school in the
morning.

41. My father was not at home as much as my mother wanted him to be.

42. As a child I was not absent from school very often.

43. I get attached to people easily.

44. When I love someone, I feel that the person is a part of me.

45. I used to wish I had a different father.

46. I am a calm and relaxed person.

47. My mother liked most of our neighbors.

48. I am a self-conscious person.

49. I have a sweet-tooth.

50. I have often felt that my father needed me as much as I needed
him.

51. When I think about growing old I don't worry about being alone.

52. My motto is, "If you want something done right, do it yourself."

53. When I was a child I felt nervous about returning to school after

a vacation even when I really wanted to go.

150

Completely Mostly Mostly Completely
True True False False
1 2 3 4

54. Sometimes I think I need more love than anyone could possibly
give me.

55. Adolescence was not a particularly difficult time for me.

56. If people I care about knew how I really felt about them sometimes,
they would not like me.

57. My family is not exceptionally close.

58. My parents encouraged me to make my own decisions.

59. If I ever let out all the anger in me I might really damage
someone.

60. It is possible to feel both love and hate for the same person.

61. When someone rejects me I get very angry inside.

62. My father likes to tell me what to do.

63. I am not afraid of failing.

64. I feel guilty when I think negative things about my mother.

65. I am a talkative person.

66. No one will ever love me as much as members of my family do.

67. I like being held as much as I like sex.

68. My father is not overprotective toward me.

69. When people I am close to go away on a trip, I worry that some-
thing might happen to them.

70. I react strongly to being rejected, even by people whom I don't
know very well.

71. The thought of committing suicide over failing at something does
not occur to me.

72. I used to regularly have big fights with my father.

151

Completely MOstly Mostly Completely
True True False False
1 2 3 4

73. I don't feel responsible for my mother's happiness.

74. I love to eat.

75. I am afraid of my father.

76. For most of my life I was an underachiever.

77. When someone is late for an appointment with me I immediately
think that he/she is not going to show up.

78. My father was deeply involved in the emotional life of our family.

79. My mother is not overprotective toward me.

80. I feel scared when someone I am close to goes away.-

81. It doesn't bother me if someone close to me disagrees with me on
an important matter.

82. I think I am sexy.

83. My parents never discouraged me from moving away from my hometown.

84. I get jealous when I see a close friend of mine having a really
good time with someone else.

85. I have almost always worked up to my potential.

86. I like the way my face and body look.

87. I feel guilty when I think negative things about my father.

88. I don't depend on others too much for my happiness.

89. There was hardly any sibling rivalry in my family. (If only
child, leave blank.)

90. I don't get angry when other pe0ple try to tell me what to do.

91. I am not prone to depression.

92. As a child I spent a lot of time with my parents.

93. My mother likes to tell me what to do.

152

Completely Mostly Mostly Completely
True True False False
1 2 3 4

94.
95.
96.
97.

98.

99.

I don't think I'm very attractive/handsome.

I feel guilty when I leave someone.

It's not hard for me to really let go.

I tend to overexplain things to people.

From the very first day of kindergarten I enjoyed school and
couldn't wait to go.

My father had no difficulty expressing his true feelings.

APPENDIX I

TWIN BACKGROUND QUESTIONNAIRE USED FOR TWIN SAMPLE

Background Questionnaire. Please check the appropriate response to
the following questions. Numbers following responses are for coding
purposes only, so you can ignore them.

 

1. Age: 18(1) 23(6)
19(2) 24(7)
20(3) 25(8)
21(4) over 25(9). Please state your
22(5) age if you are over 25:
2. Sex: Female(l)
Ma1e(2)
3. Race: Black(1)
White(2)
Other(3)
4. Marital status: Single(1)

Living with someone you are romantically
involved with, but not married(2)

Married(3)
Separated(4)
Divorced(5)
Widowed(6)
5. I am a student: Yes(1)
No(2)
6. I currently live at home with my parents: Yes(1)
No(2)
7. There were times when I was afraid to go to school as a child:
Yes(1)
No(2)
8. As a child I missed school: Less often than most children(l)

An average amount(2)
More often than most children(3)

_—

For the following questions, please pick the brother or sister in
your family that you are closest to, and answer these questions with
this person in mind. (If you are an only child, leave all of the
following questions blank--you're done.)

9. The person I am closest to is: A brother(l)
A sister(2)

10. How old is this person?

11. I currently live with this person: Yes(1)
No(2)

157

12.

13.

14.

15.

l6.

17.

18.

19.

158

This person is currently attending the same school as I am:

Yes(1)
No(2)

This person and I have alliterative names, or names which start
with the same letter (for example, Jill and Jane, Judy and Jack,
or Robert and Ronald):

Yes(1)
No(2)

During elementary school, this person and I were dressed alike:

Almost always(l)
Frequently(2)
Sometimes(3)
Hardly ever(4)
Never(5)

During high school, this person and I were dressed alike:

Almost always(l)
Frequently(2)
Sometimes(3)
Hardly ever(4)
Never(5)

Currently, this person and I dress alike:

Almost always(l)
Frequently(2)
Sometimes(3)
Hardly ever(4)
Never(5)

lllll

As youngsters, this person and I had our own secret language which
others could not understand:

Yes(1)
No(2)

I am closer to (choose only one): My mother(1)
My father(2)

The sibling that I am closest to is closer to (choose only one):

My mother(1)
My father(2)

155

 

21. How would you rate your closeness to your twin at the present
time on the following scale? Put an "X" on the line below that
indicates how close you are.

1 2 3 4 5 6 7
Not close Moderately Extremely
at all Close Close
22. The following statements may or may not describe how you felt about

being a twin when you were in elementary school. Please put a
check in front of those statements which applied to the way you
felt.
I thought that being a twin was a real drag (1)
I got tired of the comparisons that were made between my twin
and me (for example, comparisons of physical characteristics,
athletic ability, or academic achievements) (2)

I was indifferent to being a twin; it didn't affect me one way
or the other (3)

I felt that I had to do better or achieve more than my twin (4)
I like some things about being a twin, but not others (5)

I resented sharing things with my twin (for example, gifts,
time, toys, friends, and parents) (6)

I like sharing things with my twin (7)
My twin was my best friend; she/he understood me most (8)

I enjoyed being a twin; it offered a closeness that could not
be found in any other relationship (9)

I felt too competitive with my twin (10)

I liked the competition between my twin and me because it
encouraged both of us to do well (11)

Other feelings you may have had about being a twin:

 

23.

24.

My twin
a. the
b. the
c. the
d. the
e. the
I think

has:

same

same

same

same

same

I am

156

eye color as I have: Yes (1)

No (2)
body build (height and weight) as I have: Yes (1)

No (2)

blood type as I have: Yes (1)

No (2)

Uncertain (3)
hair color as I have: Yes (1)

No (2)
texture of hair as I have: Yes (1)

No (2)

a(n): Identical twin (1). (An identical twin

has the same eye color, body build, blood
type, and hair color and texture as his/her
twin. In addition, identical twins are
sometimes mistaken for one another by
teachers and casual friends. They are of
the same sex, and come from one egg.)

Fraternal twin (2). (A fraternal twin may
have the same features as his/her twin,
but the resemblance will be less than for
identical twins. While fraternal twins
may have been mistaken for one another
when they were young, as adults they
probably would not be. They can be of
either the same or different sex, and come
from two eggs.)

Uncertain (3).

159

20. How would you rate your closeness to your c
the present time, on the following scale?

losest sibling at
Put an "X" on the

line below that indicates how close you are.

 

1 2 3 4 5

Not close Moderately
at all close

6 7

Extremely
close

APPENDIX K

D IRECT ION S FOR COMPLET ION OF IN STRUMENT S

160

Thank you for responding to my request for your participation in my
research.

Enclosed you will find:

1. A 99-item questionnaire, with an answer sheet for your
answers;

2. A background questionnaire;

3. An envelope addressed to me, in which I would like to put your
questionnaires and answer sheet when you have completed them;

4. A post card addressed to me, on which I would like you to put
your name and address and phone number, so that you will be
eligible for the $50.00 lottery prize.

Directions:

 

This

1. First, complete the 99-item questionnaire, and put your
answers on the enclosed answer sheet.

2. Second, complete the background questionnaire, checking the
appropriate response on the form itself.

3. Third, insert the 99-item questionnaire, your answer sheet,
and the background questionnaire in the envelope provided
(sufficient postage is on the envelope), and mail it to me.

4. Fourth, put your name, address, and phone number on the
postcard, and mail it to me.

procedure has been designed to assure anonymity of your responses;
NO IDENTIFYING INFORMATION (NAME OR STUDENT NUMBER) IS TO GO ON THE
FORMS. The postcard, with your name and address, is sent
separately to ensure anonymity. Upon receipt of the postcard, I
will either call you (or send to you--check which you would prefer
an the postcard) to provide you with feedback on the study being
conducted.

I would also like to inform you that you have the right to withdraw from

the study at any time. If you have any questions about any of the
forms, or would like to provide me with feedback on the instru-
ments being used, please feel free to call me at 353-3726 or
332-2912. Also, if you would just like to discuss your general
reaction to being a twin, please call.

Finally, I would like to thank you once again for participating. There

Jill

are not, as you know, that many of us around (twins. that is), and
your cooperation is sincerely appreciated.

Hirt

6160 Innkeepers Court, Apt. 57

East

Lansing, MI 48823

REFERENCES

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Arlow, J. A. Fantasy systems in twins. Psychoanalytic Quarterly,
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Beit-Hallahmi, B., & Paluszny, M. Twinship in mythology and science:
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Demarest, E. W., & Winestine, M. C. The initial phase of concomitant
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Gifford, S., Murawski, B. J., Braselton, T. B., & Young, G. C.
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Jacobson, E. The self and the object world. Psychoanalytic Study of
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163

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"Illlll'lllllllllllllll