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AN INVESTIGATION OF ADAPTATION AND THE EFFECT OF
SUGGESTION ON THE ORAL READING OF

FOURTH GRADE STUTTERERS

By

ROBERT HAROLD WILLIAMS

AN ABSTRACT

Submitted to the College of Communication Arts
of Michigan State University in Partial
Fulfillment of the Requirements
for the Degree of

MASTER OF ARTS

Department of Speech

1960

”’W _ ..... 'j .
z ' $1!”—
Approvedi» 1 31:. (it ~K.~. Litter r A.-- -._L 49?;
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2
Robert Harold Williams

ABSTRACT

This study was designed to ascertain whether fourth grade stutterers
demonstrated an adaptation effect when orally reading the same material
five consecutive times. The study also attempted to discover whether
suggestion relative to the ease or difficulty of the reading passage
affected the frequency of stuttering moments and the degree of adaptation.

Eleven fourth grade stutterers from the Flint Public Schools and
adjacent school systems participated in the study.

The stutterers read each of two reading passages five times
consecutively. The experimenter suggested that one passage was hard to
read and the other was easy to read.

The number of stuttering moments was tabulated for each reading.
The analysis of results of this study by means of £_tests indicates no
significant difference on the mean frequency of stuttering moments between
the first readings of two equated reading passages ("hard" and "easy" ).

The reading of both the hard and easy passages produced inversely
negatively accelerated curves which were similar to those found in
adaptation studies of adult stutterers. The degree of adaptation, however,
was non-significant. The tests for both adaptation measures between the
two conditions also proved to be non-significant.

Possible explanations were advanced for the failure of significant

adaptation to occur.

AN INVESTIGATION OF ADAPTATION AND THE EFFECT OF
SUGGESTION ON THE ORAL READING OF

FOURTH GRADE STUTTERERS

BY

ROBERT HAROLD WILLIAMS

A THESIS

Submitted to the College of Communication Arts
of Michigan State University in Partial
Fulfillment of the Requirements
for the Degree of

MASTER OF ARTS

Department of Speech

1960

ACKNOWLEDGEMENT

I wish to express my sincere appreciation for the
stimulating and constructive guidance received from Dr.
Ralph Leutenegger throughout the execution of this

thesis.

ii

Chapter

TABLE OF CONTENTS

I. INTRODUCTION . . . . . . . . . . . . . . . . . . .

Statement of the Problem

Importance of the Study

Limitations of the Study

Definitions of Terms Used

History and Present Status of Problem
Selection of Subjects

_Se1ection of Reading Material

Recording the Stuttering Moments
Observational Reliability
Procedure of the Experiment
Statistical Treatment of Results

II 0 “SILTS O O O O O O 0 O O O O O O O O O O O 0 O O 0

III. DISCUSSION 0 O O I O O O O O O 0 0 O O O O O O O 0

IV. SUMMARY AND CONCLUSIONS . . . . . . . . . . . . . .

APPENDIX A

APPENDIX B

BIBLIOGRAPHY

iii

Page

29
32
33
34

35

INTRODUCTION

With the exception of a few Indian tribes, stuttering appears to
be an almost universal problem. Neither the cause nor the cure of stuttering
is definitely known. Studies of stuttering etiology indicate that the
majority of stuttering problems originate prior to the age of six.

Research in recent years has been interpreted to indicate that
stuttering may be some type of learned behavior.

In early psychological research, a phenomenon commonly called
the "power of suggestion" was described. Suggestion plays an important
part in all our lives. The business of advertising is based upon this
phenomenon.

More recently, researchers in speech pathology described a
phenomenon which they called the adaptation effect. The adaptation effect
was one of the first strong clues that stuttering may be a form of learned
behavior.

This study incorporates both of these phenomena into an experimental
design to explore the stuttering of fourth grade children.

Much stuttering research has been done in college and university
clinics. Research has been recently encouraged in public school systems
due to a recognition of possible differences between clinic subjects and
public school subjects. This study was undertaken in the Public School

System of Flint, Michigan.
Statement of the Problem

The purpose of this study was to investigate the speech behavior
of fourth grade stutterers during consecutive oral readings of the same

passage.

2
The study was also designed to determine whether suggestions about

reading difficulty would influence the frequency of stuttering moments.

Importance of the Study

 

It was believed that the results of this study might reveal an
adaptation effect in the oral reading of fourth grade stutterers similar
to that demonstrated by adult stutterers. The adaptation effect might be
used therapeutically to demonstrate to the young stutterer that his
stuttering is modifiable. This study would also indicate whether the

adaptation effect was influenced by suggestion.

Limitations of the Study

It was not the purpose of this study to determine the causes of
the adaptation effect, but rather to ascertain whether this phenomenon
was demonstrable in the oral readinguof fourth grade children. Neither
did the study purport to investigate the causes of possible relationships
between the adaptation effect and stutterer's suggestibility, but simply

to determine whether or not such a relationship existed.

Definitions of Terms Used

Stuttering. "Stuttering may be defined functionally as a transient

 

disturbance in communicative, propositional language usage. The disturbance
is characterized overtly by hesitations, repetitions, prolongations, and
hypertension. Covert reactions include apprehension, anxiety, and avoidance

drives related to the act of speaking."1

 

1Mack D. Steer, "An Objective Study of the Relationship between
the Psychological Factors and the Severity of Stuttering," Journal of
Abnormal and Social Psychology (1936), 31:36-46.

3

Stuttering moment. A stuttering moment is that duration of time

 

during which overt stuttering is judged to occur in spontaneous speech or
in oral reading.

Adaptation effect. "The decrease in stuttering as measured with

 

reference to its frequency or severity that occurs when a stutterer reads

the same passage a number of times consecutively.”1

Suggestion. "Suggestion is a process of communication resulting

 

in the acceptance with conviction of the communicated proposition in the
absence of logically adequate grounds for its acceptance.”2

Suggestability. Suggestibility is the tendency to respond to

 

suggestion.

History and Present Status of Problem

 

". . . They [stutterers] are one of the very largest contingents
of the disadvantaged, and since their predicament was recorded by the
ancients it has been held to be among the more baffling of mankind's
woes."

Stuttering, because it appears to be a form of learned behavior,
may be found in almost every population regardless of social status, race,
creed, color, financial status or the individual's educational level.

Stuttering is inconsistent in it's severity over a long period of time.

 

1Charles Van Riper and Catherine J. Hull, "The Quantitative
“Measurement of the Effect of Certain Situations on Stuttering," Stuttering
in Children and Adults, ed. Wendell Johnson (University of Minnesota
Press, 1955), pp. 199-206.

2William McDougall, An Introduction To Social Psychology (rev. ed.;
Boston: J. W. Luce, 1926), p. 377.

3WendellJohnson,‘.editor, Stuttering in Children and Adults (Minnea-
polis; :University of.Minnesota Press, 1955)

 

 

4
It can originate early in life or suddenly begin in later years. Stuttering
behavior can cease after several years duration or be a millstone for life.

"Stuttering, which affects approximately six to ten out of every
thousand school children, is, from many points of view, the most
challenging of all speech defects, not only to the speech correctionist
but also to the classroom teacher."1

Not until the twentieth century has the problem of stuttering been
subjected to the experimental techniques of the scientific method.

The first systematic studies leading towards the discovery of
certain phenomena exhibited during the oral reading by stutterers were
done after the turn of the twentieth century.

The first record of counting moments of stuttering was done by
Sara Stinchfield and reported in the M.A. thesis by M. D. Steer. This
study, completed in 1933, opened a new field for research-~that of
investigating stutterers' patterns of speech. "The concept of the
moment of stuttering almost immediately suggested the feasibility of
measuring the amount of stuttering and the variations in it by the rather

obvious means of counting the moments of stuttering in systematically

obtained samples of speech."2

 

1Wendell Johnson et al. Speech Handicapped School Children
(New York: Harper & Bros., 1948), Chapter V., "Stuttering."

2W. Johnson, editor, loc. cit.

5

Numerous studiesl’

2’ 3’ 4’ 5 have verified the adaptation effect.
This phenomena was first reported in 1937,6 but apparently was preceded
by another experiment written about the same time but not published until
recently.7 Another early investigation, done between 1935 and 1937

by Spencer F. Brown, dealt with the frequency of stuttering. His

findings were published in a series of articles for the 1945 Journal of
8

 

Speech Disorders.
Three basic findings emerged from these early studies. These
were the adaptation effect, the consistency effect, and Spontaneous recovery
of the strength of the stuttering response.
These basic findings have been interpreted to indicate that

stuttering responses are similar in behavior to learned conditioned responses.

 

1G. J. Wischner, "Stuttering Behavior and Learning: A.Preliminary
Theoretical Formulation," Journal of Speech and Hearing Disorders (1950),
15:324-335.

2Wendell Johnson and Marjorie Inness, "Studies in the Psychology
of Stuttering: XIII. A Statistical Analysis of the Adaptation and Consistency
Effects in Relation to Stuttering," Journal of Speech Disorders (1939)
4:79.86. “

 

3W. Johnson and John R. Knott, "Studies in the Psychology of
Stuttering, I: The Distribution of Moments of Stuttering in Successive
Readings of the Same Material," Journal of Speech Disorders, 2 (1937),
17-19.

4E. L. Jones;"Explorations of Experimental Extinction and
Spontaneous Recovery in Stuttering," Stutteringgin Children and Adults.

5.1. Maddox, "Studies in the Psychology of Stuttering, VIII.
The Role of Visual Cues in the Precipitation of Moments of Stuttering,"
Journal of Speech Disorders, 3 (1938), 90-94.

 

6Johnson and Knott, loc. cit.

7Van Riper and Hull, loc. cit.
8Spencer F. Brown, "The Loci of Stutterings in the Speech Sequence."
Journal of Speech Disorders, X (1945), pp. 181-92.

 

Further interpretations have suggested that the adaptation effect was

due to a reduction of anxiety. Additional interpretations have indicated
that the adaptation effect is due to the decreasing intellectual significance
of the reading material.

In Stuttering in Children and Adults, Johnson notes that:

This effect [spontaneous recovery may be looked upon as a
laboratory model, so to speak, of the process that is recognized
clinically as a relapse. Like the adaptation effect, it can be
investigated under controlled conditions with a view to identifying
and evaluating the factors associated with increase and decrease in
its rate and extent.

The most important finding of research to date have been the
phenomenon found in the consecutive oral reading of stutterers. These
phenomena of adaptation, consistency and spontaneous recovery not only
provide laboratory models for the study of stuttering, but also indicate
that stuttering behaves like a learned conditioned response or learned
behavior rather than disorders or incoordinations of neurophysiological
mechanisms which subserve the speech process.

It has been thought that results of previous studies have been
influenced by stutterers' mental attitudes. Some of these mental attitudes
have been variously designated readiness, determining tendency, preparatory
set, set to respond and mental set.

Van Riper's "preparatory set" therapy is based on the fact that
stuttering is anticipated during the act of speaking. In Oliver Bloodstein's

article, "Hypothetical Conditions under which Stuttering is Reduced or

Absent,"1 he concludes that stuttering is diminished when the stutterer's

 

1Oliver Bloodstein, "Hypothetical Conditions under which Stuttering
is Reduced or Absent," Journal of Speech and“Hearing Disorders, Vol. 15
(1950), pp. 142-53. ‘

7
anxiety about his speech is reduced and he has less desire to avoid stuttering.
The "preparatory sets," anticipations, or anxieties are formed because the
stutterer has specific sound or word fears.

The stutterer may also have a general situation fear which forms
these anxieties and preconceptions into mental attitudes prior to the
act of speaking. The nature of the task, the experimenter, the materials
used or the written or verbal instructions for the task, may have directed
the stutterer to form such a mental attitude. Rees and Israel in their
study, "An Investigation of the Establishment and Operation.of Mental
Sets,"1 noted that "this direction appears as a prominent feature of thinking
and behavior. This directipn may be a consequence of experimental instructions
or it may emerge from the subjectis interpretation of the properties of
the task itself."2

In further consideration of mental attitudes it should be noted
that attitude scales reflect the possibility of the subject's interpretations
of the properties of the task, in that the attitude scales attempt to
register these preconceived self-evaluations of the individual's speech.
These evaluations or attitudes may be altered by several factors such as
physical environment, punishment for failure, or the anxiety of producing
non-fluent speech during the communicative process. Psychologists have
explored attithdes which are subjected to change due to a process known

as "suggestion." "Suggestibility," the tendency for this process to occur,

 

1Hulda J. Rees and Harold E. Israel, "An Investigation of the
Establishment and Operation of Mental Sets," Psychological Monographs.2;g,
pp. 1-26.

21bid.

8
has also been studied. Suggestion and suggestibility have been studied
in an attempt to discover their influence upon various types of response
such as physical labor, gross and fine discrimination of the five senses
and mental activities such as memory, recognition, imagination and estimation.

The anticipation and expectancy to stutter due to word, sound or
situational fears may be influenced by suggestion and the suggestibility
of the stutterer, if anticipation and expectancy can be classified as
predetermined attitudes.

"In the field of stuttering the words 'expectancy' (expectation),
'anticipation,’ 'fear' and related terms have beenmemployed by different
investigators, if not always synonymously, at least in a content suggesting
that the referents of these terms are highly interrelated."

Anticipation and expectation appear to play a strong role in
disrupting the stutterer's speech. In a study by Knott, Johnson and
Webster,2 it was found that the stutterer can anticipate the words on
which he will have verbal difficulty, with an accuracy of 94 to 96 percent.
Johnson and Sinn3 found that 98 percent of stuttered speech was eliminated
when the subjects were instructed to omit words that they anticipated

4

would be stuttered. In the Van Riper and Milisen study, the sthtterers

 

1G. J. Wischner, "An Experimental Approach to Expectancy and
Anxiety in Stuttering Behavior," Journal of Speech and Hearing Disorders
(1952), 17:139-54.

2John R. Knott , Wendell Johnson, and Mary J. Webster, "Studies
in the Psychology of Stuttering II. A Quantitative Evaluation of Expectation
of Stuttering in Relation to the Occurrence of Stuttering," Journal of
Speech and Hearing DiSorders, Vol. 2 (1937) pp. 20-22.

 

3W. Johnson and A. Sinn, "Studies in the Psychology of Stuttering:
V. Frequency of Stuttering With Expectation of Stuttering Controlled."
Journal of Speech Disorders, Vol. 2 (1937), pp. 98-100.

4C. Van Riper and R. L. Milisen, "A Study of the Predicted Duration
of the Stutterer's Blocks as Related to Their Actual Duration." Journal
Speech Disorders, Vol. 4 (1939), pp. 339-45.

could not only predict the moment of stuttering but could apparently
predict its duration as well. The stutterers in these studies had pre-
conceived attitudes as to the frequency and duration of their stuttering.
Experimenters have hypothesized that propositionality or intellectual
significance of reading material have influenced the quantity of stuttering
moments. Instructions to the stutterer may have also influenced the
frequency (and severity) of these moments. In the Parley W. Newman
study, the instructions suggested that the speaking task would be very
difficult. ". ... descriptions would be recorded and later presented to
a number of different listeners who would attempt to draw the figures
described solely from the recorded directions. It was explained that
measures based on the accuracy with which the figures were reproduced by
the listeners would be used for the purpose of studying the communicability

1 In this explanation of the instructions it was

of stuttered speech."
apparent that several factors were being used as suggestions to the

stutterer that this task was difficult. The suggestions of difficulty

were, firstly, that the stutterer was to tape record his message, secondly,
that his message must be highly intelligible to the listener, and thirdly,
the stutterer would be rated upon the listener's preformance which was
dependent upon the stutterer's speech. Newman thereby attempted to influence
attitudes in each stutterer prior to the experiment.

"It is rather widely agreed that effective therapy for a stutterer

should include techniques effecting a change in the stutterer's evaluation

 

1Parley W. Newman, "A Study of Adaptation and Recovery of the
Stuttering Response in Self-formulated Speech," Jourhal of Speech and
Hearing'Disorders,(l954),-l9:450-58.

10

"1 It has been clearly indicated by stuttering self-

of speech situations.
inventory scales and related research that stutterers fear not only the
speaking situations and form attitudes from their fear, but that they also
form attitudes about stuttering on particular words and syllables and sounds.

In the study by Maribel H. Connett,2 a deliberate attempt was made to
induce or alter an attitude by suggestion. The attitude that was to be devel-
oped was the perceived difficulty of the [t] sound. The results of this study
suggested that attitudes can be induced or influenced since the stutterers in
this study did tend to have more difficulty with the [t] sound after such
difficulty was suggested.

In the study, "Frequency of Stuttering in Relation to Induced Modifi-
cation following Expectancy of Stuttering" by Eloise Oxtoby,3 it was found
that modifying the stutterer‘s reaction to his expectation of stuttering
produced changes in the anticipatory, consistency and adaptation aspects of
his speech. Oxtoby found that increased frequency of Stuttering is more
likely to occur when the anxiety level increases, and that there was no

appreciable difference in frequency of stuttering when given directions to

stutter in a customary pattern, then to stutter in a customary pattern

 

1Irene C. Shumak, "A Speech Situation Rating Sheet for Stutterers,"
Stutteringyin Children and Adults, ed. Wendell Johnson (University of Minne-
sota Press, 1955), pp. 341-47.

 

2Maribel Happer Connett, "Experimentally Induced Changes in the
Relative Frequency of Stuttering on a Specified Speech Sound," Stuttering in
Children and Adults, ed. Wendell Johnson (University of Minnesota Press, 1955),
472:268-74. '

3Eloise T. Oxtoby, "Frequency of Stuttering in Relation to Induced
Modification following Expectancy of Stuttering," Stuttering in Children and
Adults, ed. Wendell Johnson (University of Minnesnta Press, 1955), pp. 218-25.

11
but with as little effort or tension as possible. This experimenter also
found that greater adaptation was achieved with the customary stuttering
pattern and easy stuttering pattern than with the avoidant stuttering
pattern that increase the anxiety level.

The general conclusions of the Oxtoby study were postulated seven
years earlier by Porter1 who surmised that stutterers have assumptions
which areprojected on to the situation. Porter further noted that the
stutterer seemed to base his actions upon these assumptions rather than
the actualities. Porter concluded that the stutterer's assumptions appeared
to be significantly related to the frequency of stuttering.

Researchers have studied "suggestion" and "suggestibility" to
ascertain how they functioned and under what conditions they functioned.
Hollingworth and Poffenberger2 in discussing suggestion emphasized the
fact of "uncritical acceptance of an idea coming from another person."
Woodworth hypothesized that "suggestion works when a particular stimulus
(what is suggested) arouses response without other stimuli being able to
contribute to the response."3

In investigating to find how suggestion functioned, Binet and Fére4

 

1H. V. K. Porter, "Studies in the Psychology of Stuttering: XIV.
Stuttering Phenomena in Relation to Size and Personnel of Audience."
Journal of Speech Disorders, Vol. 4 (1939), pp. 323-33.

2Harry Levi Hollingworth and A. T. Poffenberger, Applied Psychology
(new ed., enl. and rev. New York, London: D. Appleton and Co., 1923).

3Robert S. Woodworth, Psychology: A Study of Mental Life (New
York: Henry Holt and Company, 1921), p. 580.

4Alfred Binet and Charles Fore, Animal Magnetism (New York:
D. Appleton and Company, 1888, 1901).

12
found that suggested images behaved not unlike real images. The suggested
images followed the laws of optics, contrast, color mixture and retinal

1 found that digestive reaction and metabolism changed

rivalry. Hansen
with suggestions of heat, cold and eating food, like the real stimuli.

In W. Brown's study of ”Differences in Suggestibility," individual
differences were emphasized. ”It must be said at once that there are no
individual differences which are sufficiently conspicuous to justify the

"not

experimenter in calling one person "very suggestible" and another
suggestible."2 Brown noted that ". . . the most skeptical individual will
yield at times with surprising readiness to suggestions, while a person
who has yielded to some test [pf suggestion] with very little apparent
resistance will unexpectedly become very recalcitrant."3 Brown, however,
maintained that the absence of conspicuous cases of high or low suggestibility
consistently maintained throughout a number of tests can not be taken as
proof that there may not be a tendency in some individuals to be suggestible
or to resist suggestion.

In a study by Margaret Otis,4 "A Study of Suggestibility of Children,"
of grades three to six, it was found that the tendency of suggestibility

did not vary appreciably through several grades, but the range in the case

of third and fourth grade children indicated that they may respond more to

 

1K. Hansen, "Zur Theorie der Symptomenbildung in der Neurose,"
Der Nervenarzt, Vol. 1 (1928), pp. 21-26.

2Warner Brown, Individual and Sex Differences in Suggestibility
(Berkeley: University of California Press, 1916), p. 430.

3Ibid.

4Margaret Otis, "A Study of Suggestibility of Children," Archives
of Psychology, No. 70 (May, 1924).

l3
suggestion. She also noted that direct suggestions were easy to resist.

The findings of the Otis study were substantiated several months
later by Irene Case Sherman, who noted that suggestibility tends to decrease
with the increasing age in normal children. Sherman1 also noted that
suggestability depends upon the type of test used to measure suggestability.

The term suggestion has been used in abnormal psychology to describe
responses found in conditions such as hysteria and hypnosis; it has been
used in social psychology as a concept to explain in part the process of
acquisition or change of attitudes; and it has been used in experimental
(laboratory) psychology in ways which seem to be efforts to measure the
first two conceptions.

The older theories dealf with the response to suggestion as a special
type of response, and with suggestibility as a trait. Later studies, such
as those of Krech and Crutchfield,2 rejected this conception and stressed
perceptual and cognitive factors in suggestion. “A number of these later
experiments found that perception and cognition play a significant role in
suggestion and suggestibility. However, many of these experiments had
disregarded motivational and experiental factors.

The basic assumption of Herbert Kelman's3 study entitled "Effects

of Success and Failure on 'Suggestibility' in the Autokinetic Situation,"

 

1Irene Case Sherman, "The Suggestibility of Normal and Mentally
Defective Children," Comparative Psychological Monographs, Vol. II,
Serial No. 9 (August, 1924), pp. 1-34.

2D. Krech and R. S. Crutchfield, Theory and Problems of Social
Psychology (New York: McGraw-Hill, 1948), p. 332f. '

 

3Herbert C. Kelman, "Effects of Success and Failure on 'Suggestibility
in the Autokinetic Situation," Journal of Abnormal and Social Psychology,
Vol. 45 (1950), pp. 267-85.

14
was that the response made to suggestion followed the same laws of
learning as any other response; that it was learned through the process of
differential reinforcement. Kelman observed by experiments and by relevant
personality inventories that suggestibility reflects an individual's previous
experiences.

In the study by G. M. Whipple,1 it was noted that suggestion was
a process that occurred in the normal consciousness which could create
belief or affect judgment.

Experiments have shown that the efficiency and amount of physical
work can be effected by suggestion. Strong,2 used a hand dynamometer and
found that positive suggestion was superior to negative, visual to auditory,
and that when the subject voiced the suggestion, it was the most effective.
He also noted that the amount of work was increased, but that the accuracy
was disturbed. Manzer,3 found similar results with his study which
emphasized verbal suggestion.

Brown,4 attempted to determine the ability of suggestion to change
performance of several types of behavior. His study is representative of
many previous studies mentioned above. Brown tested eight areas of

behavior: the five senses, for sensation and change; memory; recognition;

 

1G. M. Whipple, Manual of Mental and Physical Tests. Pt. II
(Baltimore: Warwick and York, 1924), 336 pp.

2E. K. Strong, "The Effect of Various Types of Suggestions on
Motor Activity,” Psychological Review, Vol. 17 (1910), pp. 279-93.

3C. W. Manzer, ”The Effect of Verbal Suggestion on the Output and
Variability of Muscular Work,9 Psychological Clinic, Vol. 22 (1934), pp. 248-56.

 

4Warner.B‘rown, loc. cit.

15

imagination; illusion; estimation; proportion; and esthetic preference.

The aforementioned studies have been designed to test the effects
of suggestion and suggestibility. Additional studies concentrated upon
the factors which determined the acceptance of suggestion, and the contributing
factors that determined the tendency of suggestibility.

In Thomas Coffin's studyl "Some Conditions of Suggestion and
Suggestibility: A Study of Certain Attitudinal and Situational Factors
Influencing the Process of Suggestion" the earlier and later studies of
suggestion were grouped into four classifications. The first classification
consisted of those studies of ideomotor suggestion. These studies were
based upon the premise that suggestion was influenced by sensory perseveration,
simple repetition of a previous response, suggestion by sensory set,
expectancy induced by non-verbal stimuli, verbal-motor suggestion and verbal
suggestion which touched off an attitude or set. The second classification
consisted of prestige suggestion which dealt with the emotional aspect of
suggestibility which included prestige by personal influence and negative
suggestibility to prestige. The third general claSSification was
suggestibility as a trait. This classification included studies which
dealt with individual differences, and which compared the results of
different suggestibility tests to determine whether suggestibility can be
.established as a consistent character or personality trait. The last
Classification included studies which dealt with the particular conditions

. under which suggestion and suggestibility occurred. The results of these

 

1Thomas E. Coffin, "Some Conditions of Suggestion and Suggestibility:
A Study of Certain Attitudinal and Situational Factors Influencing the
Process of Suggestion," Psyphological Monographs, Vol. 53, No. 4 (1941).

16
studies indicated that the conditions of investigation seem almost as
important as the types or individuals or groups being tested.

Coffin sununarized that suggestion seemed to be a general term
that included many psychological processes. Coffin indicated that the
evidence of previous research had not pointed conclusively to any uniform
differences between the sexes or individuals. He also noted that
suggestibility was not a matter of degree, and for this reason the conditions
under which suggestibility occur must be specified.

The results of the studies of suggestion and suggestibility indicate
several pertinent factors for the design of this study. Response may be
modified by suggestion. The five senses, cognitive behavior, non-symbolic
responses and symbolic responses have been modified by suggestion in past
studies. It is pertinent to this study that third and fourth grade
children were found to be more suggestible than older children. It is also
pertinent that suggestion has no uniform difference in effecting response
between individuals of the same age and grade level and that opposite
sexes of the same age and grade respond equally well to suggestion. It
is further noteworthy that suggestion is not dependent upon I.Q. per se
but dependent upon the acquired knowledge of the individual.

"In addition, the favorable effects of suggestion on stuttering .
are probably due, ultimately, to the reduction of anxiety upon stuttering."l

In view of the aforementioned data, the experimenter has chosen
fourth grade children for this study, as age and knowledge in one grade
level would be fairly consistent. Children of this age and grade would

also have a greater tendency to respond to suggestion.

 

1Bloodstein, loc. cit.

17
The experimenter attempted to determine whether suggestion would
affect the stutterers' frequency of stuttering by suggesting that two_equated
reading passages were of different difficulties, i.e., one was hard and

the other was easy.

Selection of Subjects

 

Eleven subjects, ten male and one female, were selected from the
fourth grade of the Flint Public Community Schools and from classes of the
Mott Foundation Speech Correction Program in Genesee County, Michigan.

The Mott Foundation Speech Correction Program has been established to serve
the speech correction needs of the parochial and county school systems.

The criteria for the subjects were as follows: no articulation problem

so severe as to render the subjects' speech incomprehensible; a previous
diagnosis of "stutterer" by a speech correctionist certified to teach in
the state of Michigan; and a minimum of eight speech non-fluencies regarded
as stuttering when reading 150 words of fourth grade reading material.

It was presupposed that a child in the fourth grade could read fourth grade
material. No extremely dull or mentally retarded children were accepted
for the study. The classroom teacher's judgment was accepted as valid

for this last criterion.

Selection of ReadingfiMaterial

 

Two reading passages, 150 words in length, were composed by the
experimenter with the assistance of an elementary school classroom
consultant and remedial reading teacher of the Flint Public Schools.

These passages constitute Appendices A and B of this study.

18

Both reading passages were adopted from a fourth grade reading
text previously read by the subjects a minimum of one month prior to the
experiment. It was assumed that a one month or longer interval between

readings would minimize the children's familiarity with the reading

passages.

Reading Passage I (in Appendix A) was equated with Reading Passage

II (in Appendix B) using Brown's word-weights.1

Every word in each passage was assigned a weight from zero
to four. The weight assigned to a word depended on how many of the
following conditions it met: (1) first, second, or third word in
a sentence; (2) beginning with an initial consonant; (3) five or
more letters in length; (4) noun, verb,tadjective, or adverb in grammatical
function. If none of the above conditions were met, it received a
weight of zero. Thus each word was placed in one of five weight

categories.2

The reading passages were also equated by using Flesch's formula

for "Ease of Readability."3

Both reading passages were judged to be non-emotional in content.
Recording the Stuttering Moments

The experimenter recorded as moments of stuttering all repetitions
of syllables, words, or phrases. Hesitations between words or sentences
and during words judged to be abnormally long to the experimenter also were
recorded as moments of stuttering. Interjections preceding or during the
reading passage were classified as moments of stuttering. Undue prolongations

of any syllable were recorded as moments of stutterings.

 

Spencer F. Brown, 10c. cit.

2W. Ed Johnson, loc. cit.

3R. Flesch, How to Test Readability (New York: Harper and
Brothers, 1951).

19
The inclusion of reading errors in the tabulation of stuttering
moments was minimized by presenting the subject with a list of all the
words found in both reading passages prior to reading them. The experimenter
clarified for the subject any words with which he was unfamiliar. The
experimenter clarified these words by using a synonym and by using the

synonym or word in simpler context.
Observational Reliability

In order to determine the experimenter's observational reliability,
the experimenter marked words stutterediin tape-recorded speech samples of
two stutterers on two separate days, one week apart. . A

By using the formula "Reliability = C/WJ;-," in which C represents
the number of words marked as stuttered on both days, and x and y represent
the number of words marked on each of the two days, respectively, the
experimenter's reliability was computed to be .90. The ratio of the
words marked on both days to the total number of different words marked
on either day was determined as .87.. The experimenter's consistency index,
obtained by dividing the total number of words marked on the first day by
the total number of words marked on the second day, was .94. “These three
scores of reliability compare favorably with the mean values of .72,

.57, and .87 respectively, obtained by Tuthill for a group of experienced

speech clinicians.1

 

1C. E. Tuthill, PA Quantitative Study of Extensional Meaning With
Special Reference to Stuttering,” Speech Monographs (1946) [13:81-98.

 

20

Procedure of the Experiment

The experimental study was conducted in the elementary Flint Public
Schools of Flint, Michigan. Children in the Mott Foundation Speech
Correction Program were transported to the Flint Public Schools by their
parents. These children were tested at the Durant Tuuri-Mott Special
Education Building of the Flint Public Schools.

Letters seeking cooperation were sent to the principals of the
schools involved in the study. A letter was also sent to the parents of
the children asking their permission to have their children participate in
the study.

The experimental environment was quite variable due to the varied
facilities available in the schools. The criteria for selection of the
testing room were that the room be available for at least 30 minutes
with no interruptions; that the room have one electrical outlet and that
.the room be sufficiently lighted and moderately quiet. The experiment
was conducted after the normal school hours. The experimenter traveled
to the various schools with the appropriate equipment for testing,

i.e., the tape recorder, music stand, reading materials and electrical
extension cord.

The subjects were tested individually. The subject was seated in
a chair directly facing the experimenter. The experimenter read the
following directions to each subject:

WILL YOU PLEASE LOOK AT THE LIST OF WORDS IN FRONT OF YOU AND TELL
ME WHICH WORDS YOU DO NOT KNOW.

The experimenter then clariffed for the subject any words be

designated. These words were noted on the experimenter's copy of the

21
reading passage. Upon completion Of the word-classification, the directions
continued as follows:

PLEASE HAND ME THE LIST OF WORDS THAT YOU HAVE JUST LOOKED AT.
THANK YOU . . . . . HERE IS A FOLDER WITH A READING INSIDE, BUT PLEASE DO

NOT OPEN IT YET. IN THE FOLDER IS SOMETHING VERY hard TO READ. I WOULD

easy

LIKE YOU TO READ ALOUD TO ME THIS 22:; READING, BUT DO NOT STOP TO ASK
QUESTIONS ONCE YOU HAVE BEGUN TO READ. WHEN I POINT MY FINGER AT YOU,
OPEN THE FOLDER AND READ. WHEN YOU HAVE FINISHED READING, CLOSE THE
FOLDER AND LOOK AT ME. EVERY TIME I SIGNAL BY POINTING AT YOU, RE-OPEN THE
FOLDER AND READ AGAIN WHAT IS ON THE PAGE. PLEASE REMAIN QUIETLY IN YOUR
CHAIR WHEN YOU ARE NOT READING. DO YOU HAVE ANY QUESTIONS ABOUT WHAT YOU
ARE TO DO?

After a short pause to answer any questions and to see whether the
subject was comfortably seated, the directions continued as follows:

HERE Is THE hard PASSAGE FOR YOU TO READ.

easy
(hard) TAKE ALL THE TIME YOU NEED, SINCE THE PASSAGE IS QUITE DIFFICULT
AND I THINK YOU WILL FIND IT HARD TO READ. (easy) YOU MAY TAKE ALL THE
TIME YOU NEED, BUT I THINK YOU WILL FIND THE READING IS QUITE EASY.

As explained in the preceding instructions, the reading material
was placed in a manila folder which was Opened and read by the subject
when instructed by the experimenter. A duration Of approximately ten
seconds elapsed between trials. A trial shall be interpreted to mean one
complete reading of the reading passage.

Subjects for whom eight or more stuttering moments were recorded
for the first trial, were instructed at the end of their fifth trial to

read the other reading passage and the following additional instructions

were given:

22

PLEASE HAND ME THE FOLDER THAT YOU HAVE JUST FINISHED READING. I
AM ABOUT TO GIVE YOU A DIFFERENT FOLDER. IN THIS FOLDER IS A PAGE QUITE
A BIT DIFFERENT FROM THE ONE YOU HAVE JUST READ. THIS PAGE IS VERY
:::§ TO READ. PLEASE KEEP THE FOLDER CLOSED UNTIL I SIGNAL YOU BY POINTING
MY FINGER: THEN, OPEN THE FOLDER AND READ ALOUD TO ME THE :::: PASSAGE.
WHEN YOU HAVE FINISHED READING, CLOSE THE FOLDER AND LOOK AT ME. EVERY
TIME I SIGNAL, BY POINTING, OPEN THE FOLDER AND RE-READ WHAT IS ON THE
PAGE. PLEASE REMAIN QUIETLY IN YOUR CHAIR WHENgYOU ARE NOT READING.

DO YOU HAVE ANY QUESTIONS ABOUT WHAT YOU ARE TO DO?

After a short pause to answer any questions, the directions
continued as follows:

easy

HERE IS THE hard PASSAGE FOR YOU TO READ.

(easy) YOU MAY TAKE ALL THE TIME YOU NEED, BUT I THINK YOU WILL FIND THE
READING IS QUITE EASY.

(hard) TAKE ALL THE TIME YOU NEED, SINCE THE PASSAGE IS QUITE DIFFICULT AND
I THINK YOU WILL FIND IT HARD TO READ.

The instructions to the subject contain alternate words and phrases.
When the subject was to read the easy passage, the words and phrases
denoting easy were read by the experimenter. When the hard passage was
to be read by the subject, the alternate words and phrases denoting hard
or difficult were read by the experimenter.

In order to guarantee a sufficient number of subjects, a tape
recorder was used to record the subject's reading, in theihopes that it would
raise anxieties and hence increase stuttering. The microphone was placed
in an observable position near the subject. The tape recorder used was
a Wollensak Dual-Speed Hi-Fi Recorder, Model T-1500. The microphone was

the standard component of this model. This microphone is a unidirectional

23
ceramic type, capable of receiving frequencies of 40 to 15,000 cycles per
second according to the manufacturers' specifications.

An interval of approximately one minute's duration occurred between
the readings of Reading Passage I and Reading Passage II.

Subjects who did not stutter the required eight or more times on
the first reading trial were dropped from the study immediately following
the completion of their first trial.

To minimize any possible effect of the order of presentation of
the two different reading passages, the order of presentation was
alternated. Every second subject read Reading Passage II first, the remaining
subjects read Reading Passage I first. All subjects read both reading
passages. Reading Passage I was designated as "easy" and Reading Passage
II as "hard" by flipping a coin.

The experimenter had mimeographed copies Of the reading material
and recorded his Observations for each successive trial on a separate
mimeographed sheet. Each mimeographed sheet as it was completed was
placed out of sight of the experimenter and the subject.

A standard collapsible portable music stand separated the experimenter
and subject. A 12 x 22 inch piece of construction cardboard was placed
on the music stand. This music stand was so positioned as to prevent the
subject from seeing the motions of writing made by the experimenter.

The experimenter recorded all stuttering moments on his mimeographed
copy with a circle for the syllable, word or phrase concerned and with a
slash mark or diagonal line for the interjections concerned.

During a practice period of two weeks, the experimenter familiarized
himself with recording moments of stuttering by using the above coding system.

The speech samples used by the experimenter for practice were tape-recorded.

24
Two sixth-grade stutterers recorded different reading passages. These
reading passages were used to determine the experimenter's observational

reliability prior to use as practice material.
Statistical Treatment of Results

The first and fifth trials and the first and second trials of
both the "hard" Reading Passage II and "easy" Reading Passage I were to be
compared separately by use of the 5 test. The 5.percent:level of
significance was used to test the hypothesis that_the value of the differences
of their respective means is zero.

The formula for the 3 test is as follows:
‘M

 

t__J__
.. SMD
‘where
LA : D ; (D = X1 - X2) :‘(X = Subject's total
I) N number of stuttering
moments on a given trial)
5 1% (NED2 - (ZD)2)
M :

 

N-l
The formula used to derive the‘g values was an adaptation of
formula 6a found on page 107 Of Psychological StatiStics by'McNemar.1
The adaptation of this formula is explained on pages 107, 108, and 109.
The number of stutterings on Trial 1 of the "hard" Reading Passage
II were compared with Trial 1 Of the "easy" Reading Passage I by use of the

£_test at the 5 percent level of significance to determine whether the

 

1Quinn,McNemar, Psychological Statistics (2nd ed.; New York:
John Wiley, 1955).

25
stutterer's "set" made an initial difference between the two reading
passages.

The adaptation scores (Trial 1 leSs Trial 5) on Reading
Passage II were compared with the adaptation scores on Reading Passage I
by use of the £_test at the 5 percent level of significance to determine
whether the stutterer's "set" affected the degree of adaptation.

These tests were also made utilizing another adaptation score.

The formula used was " Adaptation = X - Y " where X = the number of
X

stuttering moments in Trial 1 and Y = the number of stuttering moments in

Trial 5.

26

RESULTS

The mean frequency Of stuttering moments was computed for the five
trials of each of the experimental conditions. These figures are photted
in Figure 1. An inspection of the graph reveals a steady decrement from
reading to reading in both of the experimental conditions which indicates
that adaptation occurred. The frequencies recorded for the hard passage
were consistently higher than those for the easy passage.

An inspection Of the individual Scores reveals a'general tendency
of all subjects to stutter less on all Of the trials with the exception of
some minor inversions Of the first and second trial for two subjects and
the second and third trial of two other subjects on the easy reading
condition.

"Similar minor inversions are noted in inspecting the scores for
the hard condition. These inversions were not consistent for individuals
from condition to condition.

On further inspection of the raw data for individual subjects,
it would appear that the suggestion played an important role in the first
trial of the hard condition in that more than one-half of the subjects
stuttered one-third to one-half again as much in Trial 1 of the hard
condition as they did in Trial 1 of the easy condition.

Upon inspection of the raw data it was noted that all but one Of
the subjects stuttered more in the hard condition than in the easy condition.

Inspection of the adaptation (Trial 1 minus Trial 5) figures for
individual subjects reveal a "difference score" range of 0 to 14 for the

easy condition and a range of 3 to 27 for the hard condition. The

27
adaptation ratio scores yielded individual ranges from 0 to .60 for the
easy passage and .16 to .75 for the hard passage.

For purposes of more systematic comparisons a E test was run to
determine whether or not the subjects adapted between the first and fifth
trial in each of the two conditions.

The obtained-g values of 1.73 and 1.61 for the hard_and easy
conditions respectively were not significant at the 5 percent level.

Hence, although inspection of Figure 1 reveals adaptation, the size Of
this difference is not significant as tested.

Inasmuch as differences between Trials 1 and 5 were non-significant
for both conditions, no tests were made between Trials 1 and 2.

TWO tests were made of the Significance of the difference between
the easy and hard conditions. The.£ test of the differences Of adaptation
between the two conditions was based on the raw score differences between
Trial 1 and Trial 5. The £_value based on these difference scores was
.82. This difference was not significant. The second test of the difference
in adaptation between the two conditions used as its criterion measure the

ratio X - Y. The resultant E'of .48 was also non-significant.
‘ X

To determine whether the stutterer's set made an initial difference
between the two reading passages, a £_test was run comparing the number of
stuttering moments of Trial 1 of the hard condition to Trial 1 of the easy

condition. This t’of 1.08 was not significant.

23

21
20
19

18

O—‘D—‘i—‘H
WIFWC‘

H
N

...:

Frequency of Stuttering Moments
oo .o o I:

(‘O

 

Key:

Easy reading passage E]

Hard reading passage 0

 

L

A l I

1 2. 3 4 5

Reading Trials

Figure 1. Mean frequency of stuttering moments during five

successive readings under reading conditions sug-
gested-as ”hard” or "easy. "

29

DISCUSSION

The non-significant tests for adaptation between Trials 1 and 5
in both conditions indicate, insofar as this group of subjects might be
considered an adequate population sample, that fourth grade stutterers
do not demonstrate the degree of adaptation that has been found in the
reading of many adult stutterers.1’ 2’ 3’ 4’ 5

The difference between the mean frequency of the stuttering moments
of Trial 1 Of the easy reading passage and Trial 1 of the hard reading
passage was determined to be statistically non-significant. From this
it might be inferred that suggestion did not significantly modify the
initial anxiety or anticipation Of stuttering on the hard reading passage.

The differences between the adaptation measures of the hard and
easy reading passages proved to be non-significant. The lack of significant
differences indicates that suggestion did not differentially modify
expectancy or anticipation of stuttering, and thereby the adaptation effect
of fourth grade stutterers.

Despite the non-significant findings of this study, the trend
demonstrated by this group of subjects suggests that this study might .

profitably be pursued further with a larger group of subjects and that

adaptation might be used therapeutically to demonstrate to the yohng

 

1Wischner, loc. cit.

2Johnson and Inness, lOc. cit.

3Johnson and Knott, loc. cit.

4E. L. Jones, loc. cit.

5Maddox, loc. cit.

30
stutterer that his stuttering may be decreased.

If successive studies bear out that this age group does not adapt
significantly, some of the references that could be advanced in explanation
are that (1) subjects of this age and grade do not have as high initial
anxiety levels as adults, or (2) their initial high anxiety levels do not
lower as do those of adults engaged in repeated readings of the same material,
or (3) the subjects may not be responding to the intellectual significance
of the material.

The experimenter advances several possibilities for failure to
secure significant adaptation in this study. Due to their age, the
stutterers' situational and word fears may not have been as thoroughly
conditioned as those of adult stutterers and hence their oral reading was
less susceptible to the extinction-like adaptation phenomenon. It was
the experimenter's subjective impression that some subjects appeared to
rush through the readings since the study was conducted after school hours.
In addition, the subjects were probably not sufficiently motivated to read
for the meaning of the passage. If the subjects of this study are similar
to subjects of previous studiesl’ 2’ 3’ 4 which indicated that individuals
respond differently to suggestion, it is possible that the responses
would tend to cancel each other in group averages, thereby minimizing the
possibility of group differences.

The amount of suggestion was probably inadequate for a significant

change to occur as it was given in casual oral instructions. The amount of

 

1Connett, oc. cit.
2Warner Brown, loc. cit.
3

Otis, loc. cit.

4Kelman, loc. cit.

31
suggestion might have been increased by spending more time developing the
suggestion, or by typing "hard" and "easy" on the subjects' reading
material, or by having the subjects "study" the hard reading passage over-
night, Or by forewarning the subject of the difficulty of the future task
several days in advance. The stutterer's anxiety level may have been
significantly higher if an explanation had been offered to each stutterer
stating why the passage would be hard for him in terms Of his own stuttering
patterns. Perhaps both channels of auditory and visual suggestion should
have been used simultaneously.

In retrospect it seems thcte may have been profit in asking the
subjects whether or not they felt the suggestions had affected their
attitudes toward the task.

The minimal external suggestion utilized in the study was apparently
not sufficient to alter the stutterers' current attitudes toward his speech
or to produce a new attitude. This is consistent with general knowledge

that attitudes are not quickly modified.

32

SUMMARY AND CONCLUSIONS

This study was designed to ascertain whether fourth grade stutterers
demonstrated an adaptation effect when orally reading the same material
five consecutive times. The study also attempted to discover whether
suggestion relative to the ease or difficulty of the reading passage
affected the frequency of stuttering moments and the degree of adaptation.

Eleven fourth grade stutterers from the Flint Public Schools and
adjacent school systems participated in the study.

The stutterers read each of two reading passages five times
consecutively. The experimenter suggested that one passage was hard to read
and the other was easy to read.

The number of stuttering moments was tabulated for each reading.

The analysis of results Of this study by means of‘g tests indicates no
significant difference on the mean frequency of stuttering moments between
the first readings of two equated reading passages ("hard" and "easy").

Although the reading of both the hard and easy passages produced
inversely negatively accelerated curves similar to those found in adaptation
studies of adult stutterers, the degree of adaptation was non-significant.
The tests for both adaptation measures between the two conditions also
proved to be non-significant.

Possible explanations were advanced for the failure of significant

adaptation to occur.

33

APPENDIX A
READING PASSAGE I "EASY"

When the first men and women came to America, there were no
schools. Have you ever wondered how the boys and girls in those days
learned to read and write?

In one town, a woman started a school in her house. Small
children were sent to her to learn. While the children studied, she would
spin or sew. Often she had to stop a lesson to stir or turn something
that was cooking over the open fire.

Later, some schools were built. After a time there were a good
many schools. All the people helped to build the new school.‘ The parents
of the children paid the woman for teaching them.

There was very little money in those days. Some parents gave
things to help pay the teacher. So the fathers and mothers paid the

teacher by giving her meat or fruit or some wood for her fire.

34

APPENDIX B
READING PASSAGE II "HARD"

The first schools were built of mud and logs. They had an oiled
paper for the window. There was a fireplace at one end Of the room. Each
father who sent a child to school had to send some wood for the fireplace.
There was plenty of wood in those days. The country was covered with
fOrests.

Sometimes when a father did not send his share of wood to the
schoolhouse, his children were sent home. If they were not sent home, they
were made to sit in the seats farthest from the fireplace. This was the
coldest part of the schoolroom.

People who could afford it, hired private teachers for their
children, at least for their boys. NO parents worried about giving girls
much education. However, most girls learned how to read and write. They
all learned to sew and mend. They were taught sewing at home and in

school.

35

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