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thesis entitled
THE EFFECTS OF UNILATERAL FACIAL MANIPULATIONS

ON THE EXPERIENCE OF EMOTIONS IN RIGHT- AND
LEFT-HANDED UNDERGRADUATE MEN

presented by

TRAVIS GEORGE FOGEL

has been accepted towards fulfillment
of the requirements for

 

 

 

 

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1

THE EFFECTS OF UNILATERAL FACIAL MANIPULATIONS
ON THE EXPERIENCE OF EMOTIONS IN RIGHT- AND
LEFT-HANDED UNDERGRADUATE MEN
By

Travis George Fogel

A THESIS

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

MASTER OF ARTS

Department of Psychology

1996

ABSTRACT
THE EFFECTS OF UNILATERAL FACIAL MANIPULATIONS
ON THE EXPERIENCE OF EMOTIONS IN RIGHT- AND
LEFT-HANDED UNDERGRADUATE MEN
By

Travis George Fogel

An extensive literature has documented handedness differences in lateral cerebral
organization for language and visuo-spatial functions. The current study investigated
handedness differences in cerebral organization of emotion, in particular, the valence
hypothesis, according to which the right hemisphere is dominant for the experience and
expression of positive emotions, the left hemisphere for positive emotions. It followed
Schiff and Lamon’s (1989) method of using unilateral facial contractions to induce
positive and negative moods. Seventy-eight right- and left-handed men performed four
alternating contractions (LRLR or RLRL) and completed the Depression Adjective
Checklist after each. A repeated measures ANOVA failed to reveal main effects for
handedness or side of facial contraction or any interactions between them. It did show
that, regardless of side of contraction, participants’ general sense of well-being decreased
significantly over time. Lastly, mood changes were significantly correlated with the

reported level of difliculty for contracting one side of the face.

ACKNOWLEDGMENTS
I would like to thank Lauren Harris, Ph.D., chairman of this thesis committee,
for introducing me to the literature on the neuropsychology of emotion. Dr. Harris is a
true scholar in every sense of the word and has served as an excellent role model for how
to conduct honorable research. I would also like to thank my other committee members,
Anne Bogat, PhD. and Robert Caldwell, Ph.D., for their support and insightful criticism.

Lastly, I am indebted to Kenneth Brown for offering his statistical expertise.

iii

TABLE OF CONTENTS

LIST OF TABLES .................................................................................................... vi
LIST OF FIGURES ................................................................................................... vii
INTRODUCTION ..................................................................................................... 1
Cerebral Organization for Speech and Language in Right- and Lefi-Handers .............. 2
Cerebral Organization for Visuo—Spatial Functions in Right- and Left-Handers .......... S
Left-Handedness Phenotype ....................................................................................... 6
Preference Questionnaires and Performance Tests ............................................. 7
Hand Writing Posture ....................................................................................... 10
Neuropsychology of Emotion .................................................................................... 10
Evidence for the Right Hemisphere Hypothesis ................................................. 12
Perception ................................................................................................ 14
Expression and Experience ....................................................................... 15

Evidence for the Valence Hypothesis ................................................................. 18
Expression and Experience ....................................................................... 18

Schifl‘ and Lamon's (1989) New Mood Induction Technique ...................................... 23
Cerebral Organization for Emotion in Right- and Lett-Handers .................................. 29
Studies of Handedness and Psychological Tests of Emotion .............................. 29
Handedness and Lateralization for Emotion ....................................................... 31
Perception ................................................................................................ 31
Expression ................................................................................................ 33
Experience ............................................................................................... 34

Rationale and Predictions ........................................................................................... 37
Replication of Schifi‘ and Lamon’s (1989) Mood Induction Procedure ............... 37

Test of the Valence Hypothesis for the Experience of Emotion .......................... 39

Test of Handedness Differences in the Control of the Experience of Emotion 39
Prediction #1: Mood and Side of Facial Contraction .......................................... 4O
Prediction #2: Mood and Handedness ............................................................... 40
Prediction #3: Handedness and Pre-mood Measures .......................................... 41
METHOD ................................................................................................................. 42
Participants ................................................................................................................ 42
Design ....................................................................................................................... 42

iv

Materials ................................................................................................................... 44

Informed Consent Form .................................................................................... 44
Participant Identification Form .......................................................................... 45
Medical History Questionnaire .......................................................................... 45
Personal Information and Background Questionnaire ........................................ 45
The Laterality Questionnaire ............................................................................. 45
The Profile of Mood States - Bipolar (POMS-BI) ............................................. 46
The Depression Adjective Checklist (DACL) .................................................... 49
Procedure ......................................................................................................... 50
RESULTS ................................................................................................................. 53
The Laterality Index Score ......................................................................................... 53
Consistency of Handedness ........................................................................................ 53
POMS-BI Principle Components Analysis and Exploratory Factor Analysis ............... 56
Statistical Analyses .................................................................................................... 59
Mood and Side of Facial Manipulation .............................................................. 66
Mood and Handedness ...................................................................................... 67
Handedness and Pre-mood Measures ................................................................ 68
Mood and Time of Facial Manipulation ............................................................. 68
Supplemental Analyses ...................................................................................... 70
DISCUSSION ........................................................................................................... 75
The Failure to Replicate Schiif and Lamon’s Study .................................................... 7S
Unilateral Facial Contractions and the Induction of Mood ................................. 75
Insensitivity of the Current Study’s Measures of Mood ..................................... 75
Over-Sampling of Moods .................................................................................. 77
Physical Difficulty of Facial Manipulations and Mood ........................................ 77
Procedural Differences ...................................................................................... 78
The Use of Different Statistical Analyses ........................................................... 79
Statistical Analyses Revisited ............................................................................ 81
Conclusions ...................................................................................................... 83
Handedness Differences ............................................................................................. 83
General Conclusions and Future Directions ................................................................ 85
APPENDICES
Appendix A: Informed Consent Form ................................................................ 90
Appendix B: Participant Identification Form ...................................................... 92
Appendix C: Medical History Questionnaire ...................................................... 93
Appendix D: Personal Information and Background Questionnaire .................... 94
Appendix E: Laterality Questionnaire ................................................................ 95
Appendix F: Profile of Mood States-Bipolar (POMS-BI) .................................. 97
Appendix G: Depression Adjective Checklist (Forms A, B, C, D, and G) ........... 98
REFERENCES .......................................................................................................... 103

LIST OF TABLES

Table 1- Participant Demographic Information for Right- and Lefi-Handers ............... 43
Table 2 - Means, Standard Deviations and Tests for the Homogeneity of Variances

for the Eight Items Comprising the Laterality Index Score .................................. 55
Table 3 - Principle Components Analysis for the Six Subscales of the

POMS-BI (n = 118) ........................................................................................... 58
Table 4 - Correlations Among Mood Scales for the POMS-BI (n = 118) .................... 58

Table 5 - Principle Components Analysis with Varimax Rotation for the
POMS-BI Using a Two-Factor Solution (n = 118) .............................................. 60

Table 6 - Inter-item Coefficients, Reliability Analysis and Item-Total Statistics
for the Positive Mood Scale Creating Using Selected Items fiom the
POMS-BI Two-F actor Solution (11 = 118) .......................................................... 62

Table 7 - Inter-item Coefficients, Reliability Analysis and Item-Total Statistics
for the Negative Mood Scale Creating Using Selected Items fi'om the
POMS-BI Two-Factor Solution (n = 118) .......................................................... 64

Table 8 - Correlation Coefficients for Composite Mood Change Score and
Reported Difficulty or Ease of the Facial Manipulation ....................................... 72

vi

LIST OF FIGURES

Figure 1 - Neuropsychological theories of emotional processing: The right

hemisphere hypothesis and the valence hypothesis ............................................... 13
Figure 2 - Distribution of laterality index scores for right— and lefi-handers ................. 54
Figure 3 - Scree plot of principle components analysis of first POMS-BI

administration ..................................................................................................... 57
Figure 4 - Changes in mood over time collapsing order (LRLR and RLRL) ................ 69
Figure 5 - DACL t-scores for ‘lefi-face more ditfrcult’ by order ................................. 73
Figure 6 - DACL t-scores for ‘right-face more diflicult’ by order ............................... 74

vii

INTRODUCTION

Speech, language and visuo-spatial abilities are conventionally seen as cognitive
functions. In recent years, there has also been increasing evidence for lateral specialization
in the control of emotions (Silberman & Weingartner, 1986; Davidson, 1983). Given the
evidence for handedness differences in cerebral organization for language and visuo-spatial
fimctions, the question thus arises whether there also are handedness differences in the
control of emotion. There has been little study of this. If there are such differences, then
examining them may allow us to better see how emotion is processed by the brain. In
other words, if we can show that right and left-handers also differ in other skills (e.g., the
experience of emotion), we then have the means to ask the functional utility of lateral
specialization for those skills. The major aim of the current study is to examine this
possibility by comparing right- and lefi-handers on a test designed to study laterality of
function in a new way. The new method uses unilateral facial contractions to induce
mood. By using unilateral facial contractions, one can selectively stimulate the
contralateral hemisphere of the brain. Before turning to the current study, I shall begin
with a review of research on handedness differences in lateralization of speech and
language and visual-spatial fimctions, then present a review of two major
neuropsychological hypotheses about laterality and emotion, followed by a review of

prior studies of emotion and handedness.

2
Cerebral Organization for Speech and Language

in Right- and Lefi-Handers

Until the 18608, the two hemispheres of the brain were widely regarded as mirror
images of each other, both structurally and functionally. There was only occasional
speculation, largely based on clinical observations of individuals with unilateral brain
damage, that the hemispheres were not functionally identical. These observations,
however, typically lacked essential detail, making it difficult to correlate lesion site to
behavioral abnormality with any degree of accuracy (Benton, 1984). It was not until the
work of the French physician Paul Broca in the 18605 that the concept of lateralization of
function began to emerge and to replace the older view of hemisphere equivalency. Based
on clinical studies of patients with unilateral lesions of the neocortex, Broca (1865; as
cited in Harris, 1991) concluded that the left hemisphere plays the leading role in language
filnctions.

Since Broca’s reports, lateral specialization of firnction has received a vast amount
of attention in new studies of clinical as well as normal populations. The research
supports Broca’s general proposition that the lefi hemisphere almost invariably plays the
leading role for language functions. It also shows that this is true for right-handers. For
left-handers, the picture is more complex. This literature will be discussed later.

The current evidence for language laterality comes from studies of clinical as well
as normal populations. For example, in the former category are studies of patients who
have undergone cortical excisions for the purpose of controlling epileptic symptoms. In

one well-known study, of 179 right-handed patients who were operated on the lefi

3
hemisphere, 124, or 69.8%, showed some form of aphasia following the operation. Of

254 right-handed patients who were operated on the right-hemisphere, 1, or 0.4%, became
aphasic (Penfield & Roberts, 1959). Other localization methods have yielded very similar
results. For example, Warrington and Pratt (1973) found that among right-handed
depressed patients who had been given ECT, 98% exhibited dysphasia following left-
hemisphere ECT, compared with only 2% following right-hemisphere ECT. Rasmussen
and Milner (1977) reported similar percentages with the Intracarotid Amobarbital
Procedure.l In 140 right-handers with late-onset epilepsy2 (without any history of early
brain damage), 96% showed speech-disruption following left hemisphere injection; 4%
following right-hemisphere injection. None had bilateral or mixed-speech dominance.3

In summary, the literature consistently shows the left hemisphere to be dominant
for language in nearly all right-handers. The evidence for lefi-handers is less clear.
Following Broca’s 1865 report, it was widely supposed that lefi-handers were reverse
dominant for speech and language, that is, that they “speak from the right hemisphere”
(Harris, 1991, 1993). Early support for this view came from clinical observations showing

that persons who became aphasic following right hemisphere damage were also

 

' This procedure is widely used prior to surgery to excise epileptogenic tissue. First one hemisphere, then
the other is anesthetized via a barbiturate, sodium amobarbital, injected into the femoral artery, thereby
anesthetizing the ipsilateral hemisphere. When the hemisphere for speech and language is anesthetized,
the patient experiences complete aphasia. The symptoms last only for a few minutes.

2 It is important to note that these individuals had late-onset epilepsy, because it suggests that their brains
developed normally. Insofar as they did, we can make inferences about speech and language organization
in right-handers. Had they had early-onset epilepsy, or a history of brain damage, it is quite likely that
reorganization of cerebral functions (e.g., language and speech) also occurred (Davidson, 1983).

3 Harris (1992) suggests that the term ‘bilaterality’ may be misleading as it is often misconstrued to mean
that both hemispheres are contributing equally to speech functions, which is currently not known. Snyder,
Novelly, and Harris (1990) suggest that the term ‘mixed spwch dominance’ replace the term ‘bilaterality’
as it is less likely to lead to the aforementioned inaccuracies. In the current paper, the term ‘rnixed
dominance’ will be used to avoid any misinterpretation.

4
left-handed. However, these early observations were questioned when others found

clinical cases where left-handers became aphasic following left hemisphere damage, also
known as ‘crossed aphasia’ (Bramwell, 1899). In contrast to the old view that right
hemisphere speech dominance and left-handedness are highly correlated, the accumulated
evidence indicates that the majority of lefi-handers are left-lateralized as well. The studies
supporting this view include those already cited, all of which had left-handed as well as
right-handed participants. For example, Penfield and Roberts (1959) found that of 67 left-
handed patients operated on the left hemisphere, 19, or 28.3%, became aphasic; of 22
left-handed patients operated on the right hemisphere, 2, or 9.1%, became aphasic.
Similarly, when Rasmussen and Milner (1977) examined left-handed patients with late-
onset epilepsy and without any history of early brain damage, 70% of left-handers showed
evidence of left-hemisphere speech, 15% showed evidence of right-hemisphere speech,
and 15% showed evidence of mixed-speech dominance. Segalowitz and Bryden (1983)
found similar percentages from studies of left-handed aphasic patients. They estimated
that 61.4% are left-lateralized for speech, 18.8% are right-lateralized, and 19.8% have
mixed-speech dominance. Warrington and Pratt (1973) reported similar percentages in
their study of dysphasia and ECT. In left-handers, 70% showed dysphasia following left
ECT, 23% following right ECT, and 6% following both left and right ECT (suggesting
mixed-speech dominance). Taken together, the data indicate that the left hemisphere is
the side dominant for speech in nearly all right-handers and in the majority of left-handers.

They also indicate that mixed-speech and right-hemisphere speech dominance are almost

5
exclusively limited to left-handers and that left-handers, in general, are more

neuropsychologically heterogeneous than right-handers.

Cerebral Organization for Visuo-Spatial Functions

in Right- and Left-Handers
Early research focused on the role of the left hemisphere for language and speech

fimctions. Subsequent research has identified the right hemisphere as playing a leading
role in visuo-spatial functions. Much of the initial research indicated that, in contrast to
the evidence for speech and language, visuo-spatial functions were organized in the same
way in left- and right-handers (see review in De Renzi, 1982). For example, early research
showed that recognition of faces and drawings was impaired following right-hemisphere
lesions in right-handers (Tzavaras, Hécaen & Le Bras, 1970) and left-handers alike
(Tzavaras, Hécaen, & Le Bras, 1971). Similar results have been found for spatial
disorientation and dressing apraxia (I-Iécaen & Angelergues, 1962), spatial agnosia
(I-Iécaen & Sauguet, 1971), and constructional apraxia (Hécaen, De Agostini, & Monzon-
Montes, 1981).

Newer evidence, however, suggests that left-handers have greater bilaterality in the
form of secondary left-hemisphere commitment to visuo-spatial processing. Borod,
Carper, Naeser, and Goodglass (1985) examined the relation between handedness in
aphasic patients with left-sided lesions on the WAIS Performance Scale (Wechsler, 1958)
and the Parietal Lobe Battery (Goodglass & Kaplan, 1972). Relative to right-handers,
left-handers were significantly more impaired, especially on tests of visuo-spatial

organization and construction. From these findings, the authors suggest that left-handers

6
have more left-hemisphere representation for non-verbal tasks, especially on tasks that

involve manipulation and assembly.

Studies of normal adults give a similarly mixed picture. Some studies suggest that
right- and left-handers show similar and equally strong organization for visuo-spatial
functions. These include divided-visual field studies of recognition of tachistoscopically-
projected dot patterns (McGlone & Davidson, 1973) and patterns of steady-state
potentials to the temporal and spatial fi'equencies of stimuli (Mecacci & Spinelli, 1987).
Other studies report the same directional effect in right- and left-handers, but with weaker
asymmetries in lefi-handers. These include studies of dot location (Levy & Reid, 1978),
tactual discrimination of line orientation (Varney & Benton, 1975), and learning of braille
letters by naive, sighted participants (Harris, 1980).

Taken together, the results from clinical and adult normal populations indicate that
for both right- and left-handers, the right hemisphere is dominant for visuo-spatial
functions, but that left-handers show weaker asymmetries with greater commitment of the
left hemisphere.

Left-Handednes_s Phenotype

From the research reviewed so far, it would seem easy to conclude that left-
handers are typically less strongly lateralized than right-handers. The problem, as Hellige,
Bloch, Cowin, et al. (1994) point out, is that some studies comprise a greater proportion
of left-handers with left-hemisphere language, others with more left-handers with mixed-
speech dominance, and still others with more left-handers with right-hemisphere language.

This raises the possibility that the overall weaker lateralization shown by leit-handers in all

7
of the neuropsychological measures cited earlier reflects the summing together of these

difi‘erent subgroups.

There have been many attempts to find a single method of classifying left-handers
into meaningful subgroups. One method has relied on studying handedness phenotype
because left-handers are more heterogeneous than right-handers in phenotype. In contrast
to right-handers, who individually are strongly right-handed, left-handers are much more
variable in their strength of handedness.

Pif‘erence Questionnaires and Performance Tests

To measure handedness, a variety of preference as well as performance measures
have been used. On preference tests, participants are asked to indicate which hand they
prefer to use for a variety of unimanual tasks; a Likert-type scale is typically employed to
establish strength of preference. Some of these questionnaires are short (10 items or less),
some are long (50 questions or more), some ask about preference for typical tasks, and
some ask about preference for less typical tasks (Harris, 1992). These questionnaires have
in common the skill level of the task being assessed; all emphasize tasks that require
moderate to high skill rather than unskilled acts for the simple reason that tasks requiring a
higher level of skill have been shown to be more lateralized (Harris & Carlson, 1993).
Harris (1992) found that regardless of the inventory used (as long as there were a
suflicient number of skilled tasks represented), normative studies of adults yielded a J-
shaped distribution with 85-90% reporting an overall right-hand preference, with most of
the rest reporting a left-hand preference. These tests have shown hand use for writing to

have the highest strength of preference (Kang & Harris, 1992). Left-handers, however,

8
typically show weaker preference than right-handers for other tasks (e. g., Snyder &

Harris, 1991). In other words, relative to right-handers, left-handers report using their
dominant hand for a smaller proportion of acts on whatever hand preference inventory
might be used.

Performance tests assess actual skill, including the rapid movement of pegs in a
slotted board (Annett, 1970), rapid tapping of the fingers (Provins & Magliaro, 1989), and
inserting a straight pin into holes along a metal grid (Satz & D’Elia, 1989). Like
preference tests, left-handers show weaker lateralization than right-handers, that is smaller
between-hand differences (e. g., Provins & Magliaro, 1989). Generally, preference and
performance tests are significantly correlated (e.g., Peters & During, 1979).

On preference and performance tests, left-handedness, and to a much lesser extent
right-handedness, is shown to be a continuous rather than dichotomous variable. For
purposes of categorization, however, researchers divide the continuum into a variety of
subgroups. In addition to the two main groups labeled right- and leit-handers, researchers
have used a variety of labels for ‘weakly-handed’ individuals, or those that lie between the
two main groups. Weakly-handed individuals have been called “inconsistent left-handers,”
“mixed-handers,” “ambidexters,” and “ambilaterals” (Harris, 1992). Even more numerous
than the names given to weakly-handed individuals have been the methods or criteria used
to assign such persons to their respective categories. Some researchers have used
stringent criteria. For example, Annett (1972), using a 12-item hand preference
questionnaire, classified individuals who reported using the nondominant hand on any of

the 12 items as mixed-handed. Individuals were classified as right- or left-handed only if

9
they used the same hand for all 12 tasks. Others have labeled all not perfectly consistent

right-handers as mixed-handers (e.g., Witelson, 1985). Others have separated right-
handers and lefi-handers with strong and weak preferences in order to obtain four different
groups (e. g., Ponton, 1987). Still others have used an 8-item version of the Edinburgh
Handedness Inventory (Oldfield, 1971) and a method similar to Annett (1972) but with
less stringent criteria (e.g., Peters, 1990; Peters & Servos, 1989; Ponton, 1987). This
method has enjoyed some measure of success in subclassifying left-handers and is the
method proposed for use in the current study.

In this method, respondents who reported left-hand preference for seven of eight
common unimanual tasks (to write a letter, hammer a nail, throw a ball at a target,
unscrew the lid of a jar, use a knife to cut bread, use a toothbrush, hold a match while
striking it, and hold a tennis racket), including writing, were classified as consistent left-
handers (CLHs). Participants with inconsistent hand preferences (ILHs) were those who
preferred the right hand for two or more of the eight items. When CLHs and ILHs were
compared to right-handers on two types of performance tests (tests of fine motor skills
and tests of strength), CLHs performed better with the left hand on both types of tests,
much like right-handers would, except for the direction of the hand advantage (Peters,
1990; Peters & Servos, 1989). ILHs, on the other hand, performed better with the left
hand on tests of fine motor skills, but performed better with the right hand on tests that
involved strength and skill together (e. g., throwing a ball at a target). In addition, on fine
motor skills tasks, ILH participants had smaller between-hand differences than either

CLHs or the control right-handers.

9
they used the same hand for all 12 tasks. Others have labeled all not perfectly consistent

right-handers as mixed-handers (e. g., Witelson, 1985). Others have separated right-
handers and lefi-handers with strong and weak preferences in order to obtain four different
groups (e. g., Ponton, 1987). Still others have used an 8-item version of the Edinburgh
Handedness Inventory (Oldfield, 1971) and a method similar to Annett (1972) but with
less stringent criteria (e.g., Peters, 1990; Peters & Servos, 1989; Ponton, 1987). This
method has enjoyed some measure of success in subclassifying left-handers and is the
method proposed for use in the current study.

In this method, respondents who reported left-hand preference for seven of eight
common unimanual tasks (to write a letter, hammer a nail, throw a ball at a target,
unscrew the lid of a jar, use a knife to cut bread, use a toothbrush, hold a match while
striking it, and hold a tennis racket), including writing, were classified as consistent left-
handers (CLHs). Participants with inconsistent hand preferences (ILHs) were those who
preferred the right hand for two or more of the eight items. When CLHs and ILHs were
compared to right-handers on two types of performance tests (tests of fine motor skills
and tests of strength), CLHs performed better with the left hand on both types of tests,
much like right-handers would, except for the direction of the hand advantage (Peters,
1990; Peters & Servos, 1989). ILHs, on the other hand, performed better with the left
hand on tests of fine motor skills, but performed better with the right hand on tests that
involved strength and skill together (e.g., throwing a ball at a target). In addition, on fine
motor skills tasks, ILH participants had smaller between-hand differences than either

CLHs or the control right-handers.

1 0
Hand Writing Posture

_ Levy (Levy & Reid, 1978) has proposed that hand writing posture is another basis
for classification. Hand writing posture has typically been divided into two types: inverted
and noninverted writing postures. Levy and Reid (1976) define the inverted writing
posture as one involving a “hooked” position, whereby the hand lies above the line of
writing, in contrast to the more common position where the hand lies below the line of
writing (see Appendix E). Levy and Reid (1978) report that virtually all right-handers
show the normal posture, whereas approximately 90% of left-handers show the inverted
posture. They further report that classifying left-handers according to hand writing
posture allowed them to predict cerebral lateralization for language, with inverted left-
handers showing speech dominance in the left hemisphere, and noninverted left-handers
with speech dominance in the right hemisphere. There have been numerous attempts to
corroborate this initial report. The results so far are inconsistent and some
neuropsychologists (e. g. Weber & Bradshaw, 1981) have questioned the
neuropsychological significance of hand posture (see also Harris, 1992; Levy, 1982).

Neuropsychology of Emotion
The literature on the neuropsychology of emotion has focused on three main
components of emotion: perception, experience, and expression. The perception of
emotion has been measured by examining an individual’s ability to make judgments of
emotionally laden visual or auditory stimuli as expressed either in human faces or in
speech and non-speech sounds (e. g., Harris & Snyder, 1992; Levy, Heller, Banich, &

Burton, 1983). To study lateral specialization for the perception of emotion, researchers

ll
selectively present the visual or auditory stimuli in a way designed to give an initial

processing advantage to one or the other cerebral hemisphere. A variety of methods have
been used, including dichotic listening, divided visual field presentations, and flee-viewing
of chimeric faces. If one hemisphere is superior in performance to the other (e.g., in
recognizing facial expressions or the emotional tone of a voice), that hemisphere can be
said to play the leading role for this function.

The expression of emotion has been defined as the production of affective
behavior. To study lateral specialization for emotional expression, researchers also have
used a variety of methods. One method is to measure differences between the left and
right halves of the face during either spontaneous or posed expressions (e. g., Mendolia &
Kleck, 1991; Sackeim & Gur, 1978). Another way has been to draw on reports of
emotional changes in patients with unilateral brain lesions. To the extent that unilateral
lesions have different effects depending on the side of lesion, one can infer functional
responsibility for behaviors arising or diminishing after hemispheric injury (e.g., Gainotti,
1969, 1972; Goldstein, 1939; Luys, 1890).

Finally, experience of emotion can be defined as an individual’s subjective feelings
or “felt emotion.” It has been measured using dichotic listening tasks, clinical studies, as
well as mood induction techniques (e.g., Schiff & Lamon, 1989; Deglin & Nikolaenko,
1975). Because experience lies on a continuum somewhere between perception and
expression, it is often difficult to decide the extent to which emotional experience studies
are truly studies of experience and not also studies of the perception and/or expression of

emotion.

12
Clinical and experimental studies of the perception, experience, and expression of

emotion have given rise to two main hypotheses about hemispheric specialization for
emotion: 1) the right hemisphere hypothesis and 2) the valence hypothesis. These
hypotheses are summarized in Figure la and 1b.

The right hemisphere hypothesis (Figure 1a) holds that the right hemisphere is
specialized for the perception, expression, and experience of all emotions regardless of the
valence of the emotion, that is, whether the emotion is positive or negative (e.g., Borod,
Koif, & White, 1983; Borod & Caron, 1980; Rubin & Rubin, 1980). The valence
hypothesis (Figure 1b) agrees with the right hemisphere hypothesis where perception is
concerned but differs for expression and experience. Unlike the right hemisphere
hypothesis, the valence hypothesis proposes that the right hemisphere is dominant for the
experience and expression of negative emotions, the left hemisphere for positive emotions
(Silberrnan & Weingartner, 1986; Davidson & Fox, 1982; Sackeim, Greenberg, Weiman
et al., 1982).

Evidence for the Right Hemisphere Hypothesis

If, according to the right hemisphere hypothesis, the right hemisphere is specialized
for all components of emotion, irrespective of valence, it follows that damage to the right
hemisphere should lead to an impoverishment of all these components, while leaving
cognitive functions (such as speech and language) relatively intact. On the other hand,
damage to the left hemisphere should lead to an impoverishment of cognitive firnctions
(such as speech and language) while leaving emotion relatively intact. This is an example

of a double dissociation (the inferential technique used to demonstrate localization of

 

13
a. The Right Hemisphere H jpothesis

 

Left Hemisphere Right Hemisphere
Positive Negative Positive Negative
Perception + +
Experience + +
Expression + +

 

 

 

b. The Valence H ypothesis

 

Left Hemisphere Right Hemisphere
Positive Negative Positive Negative
Perception + +
Experience + +
Expression + +

 

 

Figure l: Neuropsychological theories of emotional processing: The right hemisphere
hypothesis and the valence hypothesis.

14
fimction): Lesions to one hemisphere disturb tasks not disrupted by similar lesions to the

other hemisphere, and vice versa. This is one of the main methods used with clinical
populations. For normal populations, the methods more typically use tachistoscopic,
chimeric face, and dichotic listening tests. The following review begins with perception
studies and then turns to studies of experience and expression.

Perception. For the perception of emotion, the right hemisphere hypothesis finds
abundant support from clinical and experimental populations alike. For instance, Ley and
Bryden (1979) asked children and college students to identify the emotions of
tachistoscopically projected cartoon figure drawings displaying one of five emotional
expressions (ranging fiom extremely positive to extremely negative). The result was
significant left visual field (LVF) superiorities (indicating a right-hemisphere advantage).
Using real photographs, as well as cartoons and line drawings, Strauss and Moscovitch
(1981) found a similar LVF advantage for both smiles and frowns. Levy et al. (1983),
using a fi'ee viewing chimeric face paradigm, found a similar LVF advantage. Specifically,
participants rated a composite drawing with the smile in the LVF as more emotionally
expressive than when the smile was in the RVF. Using the same method as Levy et al.,
Carlson and Harris (1985) not only found a LVF effect for judging the “happier” face, but
the “sadder” face as well. A similar right hemisphere advantage has been found for
dichotically presented words containing both positive and negative emotional content
(Bryden, Free, Gangé, & Groff, 1991).

The evidence thus shows that for the perception of emotion the right hemisphere

plays the leading role for both positive and negative emotions. There is only modest

15
evidence to the contrary. This comes fiom two studies of right-handed college students,

both by the same first author using the same method (Renter-Lorenz, Givis, &
Moscovitch, 1983; Renter-Lorenz & Davidson, 1981). In both studies, an emotional face
was presented to one visual field and a neutral face to the other. The participants then
were asked to indicate whether the emotional face appeared on the left or the right of the
screen by pressing the response key on the corresponding side. Reaction time (RT) from
face-presentation to button press was recorded. The result was faster RTs for the right
hemifield (left hemisphere) for happy faces and faster RTs in the left hemifield (right
hemisphere) for sad faces. Unfortunately, the account of the method is unclear. For
instance, the authors say that RT was “manually recorded,” but they do not say how. The
sample size also was very small (10 per cell), and men and women were combined into a
single cell. Given these limitations, it is hard to understand why both studies found a
valence for the perception of emotion instead of the more usual right-hemisphere
dominance effect.

Expression and Experience. Possibly the earliest evidence implicating the right
hemisphere in the control of emotional expression comes from a report by Olof Dalin
(Dalin, 1745; cited in Benton & Joynt, 1960). Dalin reported the case of a fanner’s son
who, following an illness, became aphasic and paralyzed on the right side (implying a left-
hemisphere lesion). When prompted, however, he was able to “sing certain hymns, which
he learned before he became ill, as clearly and distinctly as any healthy person. . .Yet this
man is dumb, cannot say a single word except ‘yes’ and has to communicate by making

signs with his hands” (Benton & Joynt, 1960, pp. 114-115). If music is the “language of

16
emotions,” then it can be inferred that the right hemisphere is intimately involved in these

processes.

Recent clinical studies support Dalin’s early report. They show that the loss of
musical ability, or amusia, is far more common after right- than left-hemisphere damage.
In a review of the literature, Zattore (1984) demonstrated that right hemisphere damage
was associated with deficits in tasks that demanded the processing of patterns of pitches as
well as differences in timbre and that right temporal lobe damage appeared to cause the
most consistent deficits. Taken together, the findings that the aphasic can still sing and
that amusia is more likely to be acquired after right- than after left-hemisphere injury
suggest that the right hemisphere exerts primary control for music and, by implication, for
the expression and experience of emotional/prosodic elements of language.

This interpretation is strengthened by studies of the effects of right hemisphere
injury on the emotional content of speech. The earliest studies are probably those by John
Hughlings-Jackson. Finding that emotional speech was not disrupted following left
hemisphere lesions, Hughlings-Jackson (1879) suggested that emotional speech is
represented in the right hemisphere. “The speechless patient may utter ‘yes’ or ‘no,’ or
both, in different tones, merely according as he is thus excited. It is then not a
proposition, but an interjection, a mere vehicle for variations of voice, expressive of
feeling” (p. 175).

More recent studies also suggest that right-hemisphere damage impairs the
expression of emotion. The impairments appear in the affective intonations in speech

(Kolb & Taylor, 1981) and impaired expression of emotions through facial gesturing

17
(Buck & Duffy, 1980). Other evidence comes from studies of what Borod, Caron, and

Koff(1981) call facedness, which they define as “the relative intensity of expression and
the extent of movement on the left and right sides of the face” (p.381). Using facedness as
an index for the expression of emotion, Sackeim, Gur, and Saucy (1978) and Sackeim and
Gur (1978) found that left-sided composites of six different posed emotions (happiness,
surprise, fear, sadness, anger, and disgust) were judged to express emotions more
intensely than right-sided composites. Ekman, Hagar, and Friesen (1981), however,
questioned whether this effect holds for true or spontaneous facial expressions or only for
‘posed’ emotions. A study by Dopson, Beckwith, Tucker, and Bullard-Bates (1984)
suggests that it holds for both. Dopson et al. secretly photographed participants after they
had been asked to remember happy or sad experiences. They then compared these
photographs with the participants’ posed expressions of happiness or sadness. In both
conditions, the faces showed stronger expression on the left side, although the difference
was greater in the spontaneous than in the posed condition. Similar findings have been
reported by Moscovitch and Olds (1982) and Borod et al. (1983).

In summary, clinical and experimental studies of expression offer strong support
for the right-hemisphere hypothesis. For the experience of emotion, the evidence is less
clear; perhaps because it is questionable whether the methods employed have truly tapped

“experience” or whether they are more accurately defined as studies of perception of

experience.

l8
Meme for the Valence Hypothesis

As already noted, the right hemisphere and valence hypotheses are identical with
respect to the perception of emotion, so the evidence on perception already reviewed for
the right hemisphere hypothesis applies equally for the valence hypothesis. Where the
hypotheses differ is in regard to the expression and experience of emotion, where, by the
valence hypothesis, the left hemisphere has primary control for positive emotion, the right
hemisphere for negative emotion. Support for this hypothesis comes from both clinical
and normal populations.

Expression and Experience. Some of the earliest evidence was reported by Jules
Luys in the 18803. While working as a physician at the Salpétriére in Paris, Luys (1890)
noticed certain personality difi’erences between right-hemiplegics and left-hemiplegics.
Right-hemiplegics (implying left-sided lesions) were more often dysphoric, showing
despair, hopelessness, anger, heightened tendency to self-blame, self-deprecation, and fits
of crying. Conversely, left-hemiplegics (implying right-sided lesions) more often appeared
indifferent or even euphoric, as marked by minimization of symptoms, denial, emotional
plasticity, joking, elation, social disinhibition, and mania.

In 1969, Gainotti reported similar effects in a study of 150 patients with unilateral
cerebral lesions. The incidence of dysphoric, or “catastrophic” reactions was significantly
higher in patients with left-sided lesions (62% left-sided vs. 10% right-sided), whereas
indifl‘erent reactions were significantly higher in patients with right-sided lesions (3 8%
right-sided vs. 11% left-sided). Gainotti (1972) corroborated these results in a more

detailed study of 160 patients with unilateral lesions (80 left and 80 right). This analysis

19
also disclosed that the depressive-catastrophic reactions associated with left brain-damage

occurred primarily in patients with severe aphasia, generally after repeated failures in
verbal communication. Similar findings were reported by Sackeim et al. (1982). These
investigators examined reports of pathological laughing and crying (involuntary and
uncontrollable changes in emotion following a cerebral lesion). Pathological laughing was
three times more common after right-sided than left-sided lesions, whereas pathological
crying was twice as common after left-sided than right-sided lesions.

The IAP procedure, mentioned earlier, provides further support for the valence
hypothesis. For instance, Terzian (1964) noticed that his patients often had intense
emotional reactions as the anesthetic was wearing off:

Amytal on the left side provokes . . . a catastrophic reaction . . . The patient . . .

despairs and expresses a sense of guilt, of nothingness, of indignity, of worries

about his own future or that of his relatives . . . [amytal on the right side] produces

on the contrary a complete opposite emotional reaction, an euphoric reaction . . .

The patient appears without apprehension, smiles and laughs and both with

mimicry and words expresses considerable liveliness and sense of well-being

(p. 1232).

These findings were confirmed by Rossi and Rosadini (1967). Of patients showing
depression, 62% showed it after left injection, only 16% after right injection. Conversely,
of patients who showed euphoria, the figures were 75% after right injection, 38% after left
injection. Finally, only 9% of patients showed a depressed and euphoric reactions after

right-side injection.

20
Interpretation of the emotional reaction following anesthetization is difficult

because the reaction occurs when the anesthetic is wearing off, not when the patient is at
the most anesthetized point in the procedure. This raises the question whether the
emotional reaction is due directly to the action of the non-anesthetized side or to the
“waking up” of the other side. A further complication is that Milner (cited in Rossi &
Rosadini, 1967) was unable to duplicate Rossi and Rosadini’s findings. In a study of 104
patients, she found no evidence linking depressive reactions to left-sided injections and
euphoric reactions to right-sided injections. Davidson (1983) argues that methodological
differences between the studies may account for the discrepancies: 1) Milner used a
higher dose of sodium amytal, 2) injections were into the common carotid instead of the
internal carotid, and 3) her sample included many individuals with early brain damage.
Gainotti’s findings suggest a question similar to one in the amobarbital injection
studies; namely, does the person’s reaction directly reflect the action of the damaged
hemisphere or does it reflect a release of inhibition of the undamaged hemisphere? In
other words, is the catastrophic reaction associated with a left hemisphere lesion directly
due to the left-hemisphere damage or is it that the left hemisphere lesion destroyed an area
responsible for inhibiting the right hemisphere, thus allowing “catastrophic affect” to flow
fi'om the right hemisphere? This is a question that one might have supposed that the IAP
procedure could address insofar as it eliminates the possibility of the opposite hemisphere
fiom exerting an influence because it is now anesthetized. However, recall that the IAP
data are equivocal because the reactions occur when the anesthetic begins wearing off so

that the question remains as to whether the reaction is due to the unanesthetized side or

21
the “waking up” of the anesthetized side. Therefore, it might be concluded that lesion

studies support the valence hypothesis but are inconclusive about the direction because
there is no definitive way to determine whether emotional displays represent the patient’s
reactions to deficits or to the disinhibition of the non-injured hemisphere. However, by
applying Hughlings-Jackson's inhibition theory (1874) to Gainotti's findings, the
catastrophic reaction after left hemisphere damage can be seen as the result of the left
hemisphere’s release of inhibition over the right hemisphere. Furthermore, the euphoric
reaction after right hemisphere damage would be the result of the right hemisphere’s
release of inhibition over the left hemisphere. By this view, it could be argued that the left
hemisphere leads for the expression and experience of positive emotion, the right
hemisphere for negative emotion.

In addition to the evidence from clinical populations, support for the valence
hypothesis comes from mood induction experiments in normal persons. The methods used
to induce mood include having participants watch television programs with varying
emotional content (e.g., Davidson, Schwartz, Saron, Bennett, & Goldman, 1979), asking
participants to self-generate emotional states (e.g., Tucker & Dawson, 1984), and
observing emotional displays by others (e.g., Davidson & Fox, 1982). Physiological
measures such as EEG recordings are taken and hemispheric specialization for emotional
experience is inferred. Schiff and Lamon (1989), however, question the validity of such
studies. They raise the possibility that the participants’ mood states, instead of reflecting
the emotional tone of the manipulations, reflect a demand characteristic. They also raise

the question of whether the cognitive activities that these participants engaged in as part of

22
the mood induction might have reflected the lateralization for the processing of emotion as

well as the regulation of emotional experience. In other words, these mood induction
experiments might represent the perception of emotion rather than the experience of
emotion.

Other approaches have presented emotional stimuli selectively to each hemisphere
and measured emotional reactions. For instance, researchers have presented photographs
of emotional faces selectively to one hemisphere (e. g., Davidson, Schaffer, & Saronson,
1985; Natale, Gur, & Gur, 1983) and have shown films with emotional content to one
hemisphere (Dimond, Farrington, & Johnson, 1976; Dimond & Farrington, 1971). The
results were mixed. For instance, Dimond et al. (1976) found that when participants were
asked to evaluate the films for unpleasantness, the right-hemisphere condition yielded
more unpleasant judgments than the left, but found no effects for pleasantness. Davidson
et al. (1985), on the other hand, found significant differences only for the left hemisphere,
namely, that sad pictures were judged as less sad, or more happy, when projected to the
left rather than the right hemisphere; there were no significant effects for the happy or
neutral pictures. In general, the results of these experiments support a valence effect for
the experience of emotion. These experiments, however, raise the same questions as do
the studies mentioned earlier; namely, how well do the stimuli induce mood, how much of
the change in mood is due to response demands, and do these experiments truly tap
“experience,” or are they more reflective of perceptual processes? To circumvent these

difficulties, a new method of mood induction has been proposed by Schiff and Lamon

23
(1989). Because it is also the method used in the current study, it will be described in

detail.
Schiff and Lamon’s (1989) New Mood Induction Tom

Schiff and Lamon’s (1989) mood induction procedure involves the selective
contraction of the facial muscles, first on one side, then the other. The assumption is that
contracting one side of the face selectively stimulates the contralateral hemisphere. To
explain why such contractions also might be expected to affect the participant’s mood, or
emotional state, we first must discuss the anatomy of the facial sensory and motor
pathways.

The lower two-thirds of the two sides of the face innervate the brain
contralaterally. Thus, contracting the lower two-thirds of the left side of the face
stimulates the right hemisphere; contracting the lower two-thirds of the right side
stimulates the left hemisphere. Two types of neurons innervate the face. The motor
neuron brings information from the brain to the facial muscles. The sensory motor
neurons bring information to the brain from the sense receptors (Brodal, 1981, chap. 7).
There are also two motor neuron circuits. Upper motor neurons (UMNs) carry motor
impulses fiom motor centers in the brain to the brain stem or spinal cord. Lower motor
neurons (LMNs) carry the impulses from the brain stem or cord to the muscle itself. It is
the LMNs that innervate the lower two-thirds of the face. If emotional activity stimulates
motor neurons, producing a facial expression, could one enter the system by the reverse

route? Specifically, with manipulation of one side of the face, would the sensory neurons

24
send information to the brain and by spread of activation induce an emotion? This is

Schifi’ and Lamon’s supposition.

Schifi‘ and Lamon’s (1989) first report consisted of three experiments. In the first
experiment, 12 acquaintances (4 men and 8 women) of the experimenter were asked to
“pull back and lift each corner of their mouths” (p. 925). The authors selected
acquaintances who they believed would be comfortable disclosing feelings that they
presumably would find unexplainable, that is, emotions arising fi'om simple manipulation
of the face. Participants held the contractions for 60 seconds and were asked to “pay
attention to whatever emotional experiences they might have while maintaining these
contractions, to let them occur without judgment, and to report on them when they were
asked to relax” (p. 926). The experiment used a within-participants design with side of
initial contraction counterbalanced across participants. The sequence of subsequent
contractions was different for each participant and depended on the experimenter’s
judgment about the participant’s emotional state. For instance, if the experimenter
determined that a participant was beginning to show signs of emotion following
contraction of one side of the face, then that side was contracted again. Ten of 12
participants reported having emotional experiences following the facial contractions. In
most cases, the first report followed the first two or three contractions. Subsequent to
left-side contractions (activating the right hemisphere), these ten participants reported
feeling “sad and depressed” and had sad facial expressions. In addition, three participants
began to weep. None of the ten could report reasons for their mood change, and all

expressed surprise that they were feeling sad; the feelings were described as “coming

25
upon them without warning and without reason” (p. 926). When a right contraction was

performed after the left had produced the dysphoric reaction, the participants reported that
the sadness lifted and, again, could not explain why. Descriptions following right-side
contractions included reports of positive affect (e. g., “up” and “good”) and a mixture of
positive affect and aggression (e. g., “cocky” and “smug”). The two participants who did
not report emotional experiences following contractions reported feeling silly and self-
conscious while holding the contraction.

Schiff and Lamon (1989) recognized that the semiclinical procedures that were
used could not rule out whether the effect was due to the manipulation or to cues
provided by the experimenter. Their sample size was also small and consisted of their own
acquaintances. In addition, the dependent measure — self-report — was rated by the
experimenters. For these reasons, Schiff and Lamon conducted a second experiment with
30 right-handed male and female undergraduates. The instructions were the same, except
that the participants were to hold the contraction for only 45 seconds, were told to
“breathe normally throughout the contraction,” and to “attend to feelings rather than to
thoughts or facial sensory experiences” (p.929). Each participant performed four
contractions, with order of initial contraction counterbalanced (LRLR or RLRL). After
each contraction, participants were asked to report their emotional experiences. These
reports were recorded on audiotape and later transcribed onto separate pages. There were
120 reports from the 30 participants. The order of the reports was then randomized
across participants and conditions. Two independent judges (who themselves had

undergone the manipulation) then attempted to classify the reports as following a right or

26
left facial contraction. The judges agreed on 106 of the 120 reports, calling 56

classifiable and 50 unclassifiable. Of the 56 reports that could be classified, an equal
number were predicted to have occurred following right and left contractions. The judges
correctly classified 7 5% of mood reports following a right face contraction and 71% of the
mood reports following a left side contraction. A test for accuracy of prediction was
significant. These results corroborate the findings of the first experiment. A third
experiment was then performed to investigate the effects of the facial contractions using a
measure other than self-report. The authors believed this third experiment to be the most
rigorous; “this third experiment demonstrates conclusively that [if there were any
remaining questions regarding the validity of the emotional reports in the first two
experiments it] is not a problem” (p. 933).

The measure chosen for the third experiment was selected cards from the Thematic
Apperception Test [TAT] (Bellak, 1986). The emotional tone of the stories told after the
fourth manipulation was rated. Participants were 36 right-handed men and women.
Standard TAT instructions were used. Following the fourth manipulation, the participant
was presented with cards #13B and #14; these were the practice pictures and were
chosen because they were not thought to be sensitive to emotional states (Bellak, 1986).
The participant was then given the target card, card #11. The stories were audiotaped,
transcribed, and rated by two independent observers for emotional tone (positive,
negative, or neutral). Inter-rater agreement was 90%. As predicted, there were no
differences in the tone of the emotional content for the practice cards. The target picture

produced a significantly greater proportion of negative emotional content following the

27
left contraction than the right contraction. There was also a significantly greater

proportion of both positive and neutral stories following the right contraction than the left
contraction. For the stories told after the right contraction, however, analysis of variance
failed to show any significant differences between the proportion of negative, neutral, and
positive stories.

Taken together, the three experiments support the valence hypothesis for the
experience of emotion but more clearly for the right than the left hemisphere. The right
facial contraction produced fewer negative (or more positive) stories, but it could not be
further differentiated. The first and second experiment, however, found a sharper
distinction between the two facial contractions, with the right hemisphere showing more
involvement for negative experience and the left hemisphere for positive experience.
These experiments, however, were not so experimentally rigorous as the third.

In still another study, Schiff, Esses, and Lamon (1992) showed that their mood
induction procedure could produce similar effects in social cognitive judgments about
ethnic stereotypes as do positive and negative moods induced by conventional mood
induction procedures. These findings not only provide further evidence for the valence
hypothesis for the expression of emotion, they suggest that a mood’s influence on
cognition does not depend on a cognitive component of mood induction. Perhaps the
emotional state results from a spread of activation from the sensory and/or motor areas to
adjacent areas responsible for emotion, thereby affecting one’s cognitions. If the spread-
of-activation hypothesis is correct and if mood arousal does not depend exclusively on

facial musculature, then one should be able to contract other muscles with similar motor

28
organization (innervation to the contralateral hemisphere) and produce similar mood

changes. Schiff and Lamon (1994) found support for this hypothesis using unilateral
contraction of hand muscles. The procedure was the same as in Schiff and Lamon’s
(1989) third experiment and yielded similar results. Left-handed contractions produced
more negative stories; right-handed contractions produced more positive stories.

Since publication of Schifl’ and Lamon’s (1989) initial report, only one replication,
by Kop, Merckelbach, and Muris (1991), has been reported other than those by Schiff
himself. This attempt failed. This led to spirited discourse between the two sets of
authors (Schiff& Lamon, 1993; Kop, Merckelbach, & Muris, 1993). Schiff and Lamon
(1993) effectively argued that the replication was not a true replication and that this may
explain the null results. Schiff and Lamon pointed to numerous inconsistencies in the two
methods, including non-alteration of the side of contraction after each manipulation
(participants were assigned to LLLRRR or RRRLLL conditions) and use of a different
dependent measure (subjective rating of six cartoon figures — one after each contraction
— for pleasantness). Although Schiff and Lamon did not mention it in their list of
criticisms, Kop et al. also only used female participants. The Kop et al. study, therefore,
does not represent a true “replication” of the Schiff and Lamon (1989) technique.
However, as Schiff and Lamon (1993) discuss, Kop et al.’s (1991) failed replication does

show the limiting conditions under which the phenomenon occurs.

29
Cerebral Organization for E_rnotion in

Right; and Left-Hpnders

So far we have reviewed the evidence for two hypotheses pertaining to the
organization of emotion. We now can examine the evidence comparing right- and left-
handers on tasks such as those cited earlier when discussing the evidence for the right-
hemisphere and valence hypotheses. These studies are divided into two groups:
1) studies that compare right- and left-handers on presumptive tests of emotion and
2) laterality studies, like those reviewed earlier, that compare right- and left-handers on
tests of the perception and expression of emotion.
Studies of Hgndednesspnd Pfl/chologicpl Tests of Emotion

The literature on emotional/psychological differences between right- and left-
handers includes tests of emotional stability, anxiety, and temperament. One of the earliest
such comparisons was reported by Ingram and Reid in 1956 (cited in Orme, 1970). They
found a high incidence of left-handedness and emotional disturbances in children with
developmental aphasia but with normal intelligence (ages not given in Orrne’s report).
Orme (1970) made a similar investigation in 300 non-aphasic British school girls, ages 14-
17. Of these adolescents, 23 were left-handed, 277 were right-handed, as measured by the
hand used for writing. Emotional stability was measured by a 13-item questionnaire
created by Orme (1965). Using a chi-square test, Orme concluded that the left-handers
were significantly more emotionally unstable than right-handers. Indeed, only one left-
hander (4.3%) scored in the emotionally stable range compared to 89 of the 277 right-

handers (32.1%). Hicks and Pellegrini (1978) properly question Orrne’s data analysis,

30
namely that he violated the rule pertaining to the minimum number of cases per cell in a

contingency table. They also state that a more powerful statistic should have been used to
measure the strength of effect given that the emotional stability scale score Orme
computed was a parametric statistic.

Only a few studies have focused on possible links between handedness and anxiety.
Hicks and Pellegrini (1978) compared 23 left-handed, 12 mixed-handed, and 35 right-
handed college students on the Taylor Manifest Anxiety Scale (1953). Right-handers
were significantly less anxious than either left- or mixed—handers, who were not different
from each other. The relation between anxiety and handedness was also examined by
Mueller, Grove, and Thompson (1993), who drew on archival data from four studies. In
each study, handedness was based on self-report of hand-writing preference, and anxiety
was measured by the Test Anxiety Inventory (TAI; Spielberger, 1980). The total N
across the four samples consisted of 166 left-handers and 1,388 right-handers. No
significant differences were found between the two groups in base levels of test anxiety.
French and Richards (1990) and Weinrich, Wells, and McManus (1982) reported similar
null findings.

Harburg, Roeper, Ozgoren, and Feldstein (1981) approached the question
somewhat differently by focusing on temperament. Their participants were 1,153 persons
ages 18 to 70 who were participants in the Tecumseh Community Health Study. This was
a longitudinal study begun in 1959, and most of the data were medical. The protocol
included a measure of handedness (showing two different hand-writing postures for both

hands) and two measures of temperament (Buss & Plomin, 1974; Eysenck & Eysenck,

31
1968). The only differences were between the younger (18-39 year old) participants. In

this subgroup, left-handers (N=86) compared to right-handers (N=565) showed
significantly more emotionality (fear and anger), less sociability, less sensation seeking,
and less extroversion.

In summary, the relation between handedness and these measures of emotionality
is weak; sometimes it is there, sometimes not. However, when a difference occurs, it is
always in the direction of left-handers being more emotional. This, in itself, ofi‘ers some
justification for examining the lateralization of emotion.

Handedness and Lateralization of Emotion

In most of the studies on lateralization of emotion reviewed earlier, the participants
either were all right-handers or the handedness of the participants was not mentioned.
The literature on handedness and lateralization of emotion thus is slim. Nevertheless,
there are a sufficient number of studies to permit comparison of right- and left-handers on
each of the three components of emotion: perception, expression, and experience.

Perception. Beginning with perception studies, most research suggests that both
right- and left-handers show right-hemisphere dominance. Most of the evidence comes
from chimeric face and dichotic listening studies. For example, Luh et al. (1994)
compared 72 right-handers with 72 left-handers on four free-vision chimeric face tasks
that required judgments of emotion. The chimeric faces were smiling on one side and
neutral in expression on the other. They also differed in sex, one side male, the other
female. The latter difference allowed the chimeras to be rated for what the investigators

called “femininity.” Each condition included photographs of real and cartoon faces. For

32
the emotion task, participants were asked to judge which face looked happier. For the

femininity task, they were asked which face looked more feminine. For both tasks, right-
and left-handers showed left-hemispatial biases. However, the task-specific reliable
variance was decreased, and the variance common to all tasks was increased for left-
compared to right-handers. More specifically, in left-handers the left visuo-spatial bias
was higher for feminine faces than for emotion, whereas in right-handers, the emotional
content of the face was more important. This suggests that those processes that underlie
the perception of emotion are less lateralized in left-handers than in right-handers.

Bulman-Flerning and Bryden (1994) found similar results with a dichotic listening
task. They presented 64 left-handers and 64 right-handers with a target word spoken in a
happy, sad, or angry voice. They then asked them to report each time they heard a
particular word or a particular emotion. All three emotions — happy, sad, and angry —
showed a left ear advantage of similar magnitude. These results largely support Bryden et
al.’s (1991) study with the exception that, in Bulman-Fleming and Bryden (1994), the left
ear advantage was much larger for angry words than for happy, sad, or neutral words.
The left-ear advantage was reduced in left-handers, but handedness effects failed to reach
significance. As in the study by Luh et al. (1994), left-handers also showed higher
variance.

The only exception to this picture would be the works by Renter-Lorenz and
Davidson (1981) and Reuter-Lorenz et al. (1983), cited earlier. Recall that they found a
valence effect for the perception of emotion in right-handers. They also found evidence

for a reversed valence for certain left-handers, namely those who wrote in the

33
non-inverted posture. The authors therefore suggested that: 1) non-inverted and

inverted left-handers differ in their neural organization for the perception of emotion and
2) the two hemispheres are differentially specialized for positive and negative affect.
Recall, however, the suggestion raised earlier that these findings might reflect some
methodological artifact.

Keeping these two exceptions in mind, the weight of evidence shows that both
right- and left-handers are right-hemisphere dominant for the perception of emotion,
irrespective of valence. It also suggests, however, that Ieft-handers show increased
variance across different emotional tasks. The greater variance could reflect at least two,
not necessarily mutually exclusive, differences between right- and left-handers: 1) left-
handers’ weaker differentiation in cortical organization for the perception of emotion or
2) left-handers’ greater variability in cerebral organization.

Expression. Like the research on the perception of emotion, most of the evidence
on expression of emotion suggests that right- and left-handers alike show right-hemisphere
dominance. Recall that the usual method of demonstrating this effect is through the study
of facedness. For instance, Borod and Caron (1980) had 31 right-handers and 201eft-
handers perform nine different emotional expressions including greeting, disapproval,
clowning, flirting, grief, toughness, and horror. Right- and left-handers were both
significantly left-faced for all emotions except for “toughness” where left-handers were
significantly right-faced. Borod et al. (1981) found similar results, and, once again,
toughness was reversed in left-handers. It may be significant that toughness was the one

expression requiring unilateral facial movement. To study unilateral facial movements in

34
greater detail, Chaurasia and Goswami (1975) examined deliberate manipulation of the

face in 300 right- and 30 left-handers. The result was an inverse relation between
handedness and facedness. Of the right-handers, 59% showed a left-sided smile and found
it easier to perform a variety of facial manipulations with the left side of the face, whereas
73% of left-handers showed the reverse effect. Campbell (1979), on the other hand,
observed 24 left-handers while they expressed a posed smile and found them to be
significantly left-faced.‘ In support of Campbell’s (1979) results and in contrast to
Chaurasia and Goswarni’s (1975), Heller and Levy (1981) found that for right- and left-
handers alike, left-side facial composites of a posed smile were judged to be happier than
right-side composites.

The discrepancies in these studies are hard to explain in terms of
neuropsychological theory. However, the pattern of results across experiments supports
the view that both right-and left-handers are left-faced, but significantly so only for right-
handers.

Experience. In contrast to the literature on handedness, perception, and
expression of emotion, the laterality literature on handedness and experience of emotion is
sparse. One reason may be related to the difficulty in defining “experience.” A study by
McFarland and Kennison (1989) illustrates this point.

McFarland and Kennison (1989) presented music recordings to 80 right-handers
and 80 left-handers. Two selections had a negative valence and two had a positive

valence. Independent judges reported that the negative selections evoked images of

 

‘ However, a reversal in the asymmetry was observed when the participants’ facial expressions were
relaxed (based on a photograph taken after the participant performed the posed smile).

3 5
agitated grief, sadness, and despair, whereas the positive selections evoked images of

jollity, celebration, happiness, and contentment. The musical selections were presented
monaurally either to the right or left ear for 3 minutes and 40 seconds. After the music
ended, the participants were asked to “rate the valence of the emotion” they had
experienced during the music using a scale anchored by the words “happiness” and
“sadness.” Right-handers reported more positive and less negative afl‘ect when listening to
the music in the right ear, whereas left-handers showed the reverse effect, reporting more
positive and less negative affect during music to the left ear. These results, therefore,
suggest reverse valences for the experience of emotion between right- and left-handers.
But did the participants actually feel sad or happy (in other words, did they experience sad
or happy emotions), or did they simply perceive the music as sad or happy? If the latter,
then this would be a study of perception; if the former, it was a study of experience. The
authors, perhaps sensing these difficulties, use neither term and instead described the
results as showing asymmetry in the “processing” of emotions, which could mean
perception, expression, or experience of emotion, individually or in combination.

In an attempt to better understand the relation between handedness and the
experience of emotion, Smith, Kline, and Meyers (1990) made parietal EEG recordings
from right- and left-handed adults while they listened to a variety of emotional sounds.
The sounds included a woman screaming, a woman laughing, a woman crying, and a baby
cooing. The participants were instructed to process the sounds in three different ways. In
the “affective” condition, they were asked to “concentrate on feelings and actively attempt

to experience the emotions elicited by each stimulus” (p. 63). In the “cognitive

36
condition,” they were instructed to avoid making an affective response. In the neutral

condition, they were asked to focus firll attention on the stimuli and to maintain a neutral
(i.e., nonaffective, noncognitive) set. Left-handers showed a greater overall level of
activation (arousal), especially for the emotional conditions, relative to right-handers.
Right-handers showed greater overall lateralization for the three conditions with greater
left-hemisphere activation. Left-handers showed nearly identical activity in the two
hemispheres across all three conditions. This last finding corroborates the reports of
increased variability for left-handers in the perception and expression studies cited earlier,
which raises the possibility that the cerebral organization of emotional experience in left-
handers, at a group level, is more diffuse than in tight-handers.

For right-handers, then, some tentative conclusions can be drawn about the
neuropsychological organization of emotion, namely, that they show a valence effect for
the expression of emotion —- negative for the right hemisphere, positive for the left
hemisphere. Left-handers appear to differ from right-handers, but it is hard to say how
they differ with any certainty. Given the aforementioned findings and the ample evidence
of the heterogeneity of left-handers, it is plausible to hypothesize that left-handers show
increased diffusion of cerebral organization for emotion. It is far more difficult to accept
McFarland and Kennison’s (1989) conclusion that the valence is reversed in left-handers.
It is also likely that some of the increased bilaterality in left-handers occurs at a group
level when phenotypic subgroups of left-handedness are grouped together. Perhaps it is
only when these subgroups are examined separately that we can better determine whether

left-handers, in general, show greater bilaterality for the lateralization for the experience of

37
emotion, or whether it is only certain subgroups of left-handers who show increased

diffusion of cerebral organization for emotion.
Rationale and Predictions

The current study was designed to study handedness and experience of emotion by
comparing right- and left-handers on a new test using unilateral facial contraction to
induce emotional experiences. The specific aim was to 1) determine whether Schiff and
Lamon’s (1989) findings could be replicated, 2) further examine the valence hypothesis for
the experience of emotion, and, if able to replicate Schiff and Lamon’s findings,

3) determine whether right-handers differ from left-handers in cerebral organization for the
experience of emotion.
Rpm—cation of Schiff and Lamon’s (1989) Mood Induction Procedure

To date, the only attempted replication of Schiff and Lamon’s (1989) mood
induction technique, other than those by Schiff or Lamon themselves, was by Kop,
Merckelbach, and Muris (1991), and this attempt failed. Recall however, the many
inconsistencies in the two methods pointed out by Schiff and Lamon (1989). To avoid the
difficulties in interpreting Kop et al.’s null findings, the current study strictly adhered to
Schiff and Lamon’s descriptions of their mood production procedure.

Where this study purposefirlly deviated, however, was in the selection of the
dependent measures used to assess the effects of the mood induction. Recall that Schiff
and Lamon used a variety of dependent measures, self-report for the first experiment,
transcribed self-reports judged by blind reviewers for the second, and, for the third and

most experimentally vigorous experiment, three TAT cards rated for positive, negative,

38
and neutral emotional tones by two independent observers. Although the TAT lets the

researcher measure the subtle effects of experimental manipulations, it is an indirect
measure of mood and it does not allow objective measurement of the strength of the mood
state or comparison of participants’ scores to those in a normative sample. 80 that
strength of mood could be measured and compared to normative samples, the current
study used the Depression Adjective Checklist (DACL) and the Profile of Mood States-
Bipolar (POMS-BI). In addition, the DACL has multiple forms specifically designed for
the research setting and, in particular, for research involving repeated measures.5 Its
ability to be used quickly and repeatedly was of great import to the current study, as it was
important to be able to track changes in participants’ moods across manipulations.
Remember that Schiff and Lamon gave only the TAT cards after the fourth and final
manipulation. To the extent that the experiment employed a between-participants design,
Schiff and Lamon, therefore, could not make any definitive statements about mood
changes relative to side of facial contraction. Like the DACL, the POMS-BI was chosen
because of its ability to measure strength of mood and because of its established norms.
However, unlike the DACL, the POMS-BI takes several minutes to complete and does
not have multiple forms. Therefore, it was included as a pre-test measure and given after
the fourth and final manipulation, similar to Schiff and Lamon’s method. The difference
was that giving the POMS-BI as a pre-test measure allows for the control of pre-mood
differences between participants. The POMS-BI was also selected because of its reported

ability to measure six bipolar mood states. Recall that Schiff and Lamon (1989) could not

 

5 These forms have well-demonstrated test-retest reliability and construct validity (Lubin, 1994). For a
complete discussion of the DACL and POMS-Bl see Methods/Materials.

39
clearly describe the moods that occurred after a right facial contraction. Therefore, unlike

the DACL, it was believed that the POMS-BI would provide additional dimensions of
mood, ones other than the simple “positive vs. negative” dimension of the DACL.
Test of the Valence Hypothesis for the Experience of Emotion

Schiff and Lamon’s (1989) mood induction method was also selected because, of
all the methods used to date, it most clearly involves the experience of emotion. As we
have seen, other methods often involve the perception and/or expression of emotion as
well. To the extent that these methods also tap the perception and/or expression of
emotion, any inferences about lateralization for the experience of emotion remain
equivocal. Recall that the valence hypothesis postulates a valence effect only for the
experience of emotion. This makes it crucial for the mood induction method to involve
only the experience of emotion; to the extent that it involves other emotional processes, it
could be measuring something other than experience. As a result, it would be difficult to
determine whether there is a valence or right-hemisphere effect for the experience of
emotion. It is believed that the Schiff and Lamon (1989) mood induction method may be
useful for the researcher who wants a clean index of the experience of emotion.
T_;st of Hgndedness Differences in the Control of the Experience of Emotion

Lastly, the current study was intended to be a contribution to research on
handedness and the experience of emotion, a slim literature as we saw, especially where
handedness and the experience of emotion are concerned. To the extent that right- and
left-handers can be shown to differ in other psychological processes (e.g., the experience

of emotion), then we have the means to ask the filnctional utility of lateralization for those

40
processes. That is, because left-handers are reported to differ from right-handers on

selected psychological tasks and to be more common in certain clinical and other special
populations, the study of left-handedness and emotion may hold a key to understanding a
firndamental question in neuropsychology — the relationship of laterality to cognitive,
perceptual, and emotional processes (I-Ianis, 1992).

Based on the review of handedness and emotionality, three major predictions were
proposed.
Prediction #1: Mood pnd Side of Fa_c__ial Contrpction

In accordance with the literature supporting a valence hypothesis for the
experience of emotion, it was predicted that left facial contractions (right hemisphere)
would produce a dysphoric mood, and that right facial contractions (left hemisphere)
would produce a positive mood. For the DACL, it was predicted that those DACLs
completed after left-face manipulations would be significantly higher (indicative of more
syrnptomatology) than those completed after right-face manipulations. Using the POMS-
BI, it was predicted that those completed after a left-face contraction would result in
significantly higher levels of negative mood state and lower levels of positive mood state,
whereas POMS-Bls completed after a right-face contraction would result in lower levels
of negative mood state and higher levels of positive mood state.
Prediction #2: Mood and Hapdedness

Based on the literature on handedness and the lateralization of the experience of
emotion, it was predicted that right-handed males would be more clearly lateralized than

left-handers on the mood induction task. Therefore, right-handers’ moods (relative to

41
left-handers’) would be expected to change to a greater degree toward a negative mood

state following left facial manipulations and to a greater degree toward a positive mood
state following right facial manipulations. On the DACL, it was predicted that right-
handers would exhibit significantly greater changes in mood states after both right- and
left-face manipulations than left-handers. On the POMS-BI, it was predicted that right-
handers would exhibit significantly greater mood state changes on the PMS and NMS
after both right- or left-facial manipulations than left-handers.

Although there were no predictions made for consistency of handedness and the
lateralization for the experience of emotion, additional analyses were performed to
determine whether the classification of left-handers into consistent and inconsistent
subgroups acted as a predictor variable for the effects of the facial manipulations on mood.
Prediction #3: Hpndedness and Pre-mood Mwes

Lastly, based on the literature on handedness and emotionality, it was predicted
that if a difference was found on pre-mood induction mood measures, it would be in the
direction of left-handers showing higher rates of negative emotional states (e.g., anger and
depression). On the DACL, it was hypothesized that if a difference was found in pre-
mood measures, it would be in the direction of left-handers having significantly higher T-
scores on DACL-A, indicative of greater levels of depressive syrnptomatology. On the
POMS-BI, if a difference was found in pre-test measures, then it was hypothesized that it
would be in the direction of left-handers showing higher levels of negative mood states

and lower levels of positive mood states.

METHOD

Participants

Participants were 78 male undergraduate college students (40 right-handed, 38
left-handed) from the Psychology Department Human Participants Pool at Michigan State
University. Participants were enrolled in one of several large introductory (fi'eshman and
sophomore level) psychology classes and received credit in this course for their
participation. The age of the participants ranged from 18 to 29 with a mean age of 20.1
years (S1) = 1.9). Participants were treated in strict accordance with the ethical standards
of the APA

Of the entire sample, 81.8% of the participants were Caucasian, 9.1% were
Afiican-American, 5.2% were Asian-American, and 1.3% were Hispanic. The remaining
2.6% indicated that they were of Middle Eastern descent. Participants ranged from
fieshman to seniors. Of the entire sample, 37.2% were freshman, 28.2% were
sophomores, 15.4% were juniors, and 19.2% were seniors. Participant demographic
information is broken down separately for right- and left-handers in Table 1.
Man

This study used a 2 x 2 design with side of the facial contraction (left vs. right) as a
within-participants independent variable and handedness as a between-participants
independent variable. The two dependent variables were: 1) the participant’s rating of his
emotional state before the first facial manipulation and after each manipulation as
measured by the Depression Adjective Checklist (DACL) and 2) the participant’s rating of
his emotional state before the first facial manipulation and after the last manipulation as
measured by the Profile of Mood States-Bipolar (POMS-BI). Each participant performed

42

43
Table 1

Lagicippnt Demoglgpfic Inforrp_ation for Right- pnd Left-Hpnders

Right-Handers Left-Handers
N 40 38
Age 20.05 20.13
Ethnicity (%)
Caucasian 82.5 81.5
Afiican American 7.5 10.5
Asian American 7.5 2.6
Hispanic 2.5 0.0
Middle Eastern 0.0 5.3
Year in School
Freshman 37.5 36.8
Sophomore 30.0 26.3
Junior 20.0 10.5

Senior 12.5 26.4

44
two left-sided and two right-sided face contractions, alternating the side of the contraction

each time". The side of initial contraction was counterbalanced across participants, with
halfof the participants first performing a left-sided contraction (LRLR) and the other half
performing a right-sided contraction (RLRL).
Mpterials

Materials included an informed consent form, participant identification form,
medical history questionnaire, participant background and demographic survey, 8-item
handedness questionnaire, DACL, and POMS-BI.

Informed Consent Form

The Informed Consent Form (Appendix A) included the following information:
1) that the study involved examining the effects of facial muscle contractions on mood in a
normal, healthy population, 2) that the participant would be asked to complete a medical
history questionnaire, a background and demographic survey, an eight-item handedness
questionnaire, two adjective checklists, 3) that the participant would be asked to pull back
and lift one comer of his mouth and to hold that position for 45 seconds, 4) that the
participant would perform four such contractions, alternating sides for each contraction,
and 5) that the participant would be asked to complete a checklist, as quickly as possible,

following each contraction.

 

6 Schiff and Lamon (1993) found that having participants alternate side of facial contraction after each
trial (as opposed to performing several sequential same-side contractions) produced more robust and
reliable mood states.

45
Participant Identification Form

On the Participant Identification Form (Appendix B), the participant’s name and
identification number were recorded for the purpose of maintaining confidentiality. This
was the only form that identified and linked the participant name to his identification
number. Only the investigator and his designates have access to this information. All
other documents have only the participant identification number.

Medical History Ouestionpafi

The Medical History Questionnaire (Appendix C) asked whether the participant
currently or had at any time in the past been clinically diagnosed with any of the following
disorders: 1) Major Depression, 2) Bipolar, 3) Generalized Anxiety, 4) Panic, 5) Post
Traumatic Stress, 6) Substance Abuse, 7) Schizophrenia, 8) Hypertension, 9) any other
emotionally related disorders, or 10) a history of facial paralysis. This measure was
created in order to screen out individuals who would be inappropriate for inclusion in the
study.

Personal Infonnptionfiand Bapkground Ouestionpajgg

The Personal Information and Background Questionnaire (Appendix D) asked for
the participant’s full name, age, sex, years of education, academic major, and
ethnicity/race.

The Laterality Ouestionpifirp

The Laterality Questionnaire (Appendix E) asked the participant to choose which

of the following descriptions best described his general handedness: 1) strongly left-

handed, 2) moderately left-handed, 3) ambidextrous (either-handed), 4) moderately

46
right-handed, or 5) strongly right-handed. It then asked the participant to indicate his

hand preference for eight common tasks: 1) write a letter, 2) hammer a nail, 3) throw a
ball at a target, 4) unscrew lid of a jar, 5) use a knife to cut bread, 6) use a tooth brush,
7) hold a match while striking it, and 8) hold a tennis racket. These eight items were taken
fi'om the 10-item Edinburgh Handedness Inventory (Oldfield, 1971) and are commonly
used to assess degree of hand preference (e. g., Peters, 1990; Peters & Servos, 1989;
Ponton, 1987). Strength of hand preference was rated on a 5-point Likert Scale, fi'om
1 (always left) to 5 (always right). A laterality index score was created by adding the
strength of preference scores for each of the eight tasks. Therefore, scores could range
fi'om 8 (exclusive left-hand use for all items, i.e., 8 x 1) to 40 (exclusive right hand use for
all items, i.e., 8 x 5). Participants were also asked to indicate whether they wrote with an
inverted or non-inverted hand posture by circling one of two pictures depicting the two
postures. Lastly, participants were asked whether anyone (including themselves) had ever
tried to change what hand they used for certain tasks.

The Profile of Mood Stgtes - Bipolpr (POMS-BI)

The POMS-BI (Lorr & McNair, 1988) is a 72-item paper and pencil test that was
constructed to measure six bipolar subjective mood states. Each mood state is defined by
a scale consisting of 12 adjectives or phrases. One pole represents the positive aspects of
the dimension, the other pole represents more negative aspects. The six mood states are
described as follows: 1) composed-anxious, 2) agreeable-hostile, 3) elated-depressed,

4) confident-unsure, 5) energetic-tired, and 6) clearheaded-confidsed (Appendix F). The

participant was asked to rate the degree to which he subscribes to 72 adjectives on a

47
four-point Likert Scale. The choices were “Much like this” (3), “Slightly like this”

(2), “Slightly unlike this” (1), and “Much unlike this” (0). The form is designed to rate the
participant’s feelings during the past few minutes. It took between five and seven minutes
to complete the POMS-BI.

The construction of the POMS-BI grew in part from the monopolar Profile of
Mood States, or POMS (McNair, Lorr, & Droppleman, 1971). Thirty-five of the 72
adjectives in the POMS-BI were taken fi'om the monopolar POMS. Based on evidence
from several studies suggesting the bipolar and multi-factorial nature of moods (e.g., Lorr,
McNair, & Fisher, 1982; Lorr & Wuderlich, 1980), Lorr and McNair (1988) derived the
six bipolar mood states mentioned above for construction of the POMS-BI. Reliability
studies indicated that 12 adjectives were sufficient to achieve satisfactory internal
consistency. Therefore, in addition to the 35 adjectives taken from the POMS, 37 more
adjectives were added so that 12 adjectives represented each of the six hypothesized
constructs (half of them positive, half of them negative).

The POMS-BI manual does not provide clear validity and reliability scores from
standardized samples. In addition, while the POMS-BI manual summarizes several factor
analytic studies of the monopolar POMS, it does not say whether any have been
performed on the POMS-BI. It does, however, provide information on the correlations
among the six mood scales of the POMS-BI. To examine the correlations among the six
mood scales, the POMS-BI was administered to 432 university students (range .40 - .78).

To assess the degree of test-retest reliability, 66 participants completed the form a second

48
time (length of time between administrations was not stated). Correlations between time

one and time two ranged from .33 to .72.

Following Lorr and McNair’s (1988) protocol, each mood state is to be scored
separately using six hand-scoring stencils. The adjectives are scored 0, l, 2, or 3 as
indicated by the four—point Likert mentioned above. Because the scales are bipolar, a
scale score would be the sum of the positive item scores minus the sum of the negative
item scores. The total score for any of the six mood states is the sum of the positive items
minus the sum of the negative items plus 18 ($1‘2 Sp- SN + 18). The constant of 18 is
added to make all possible scores positive. Thus each scale has a possible range from
0-36.

A principle components analysis and series of principle components factor analyses
conducted on the first administration of the POMS-BI’s completed for this study indicated
that there appeared to be only two meaningful factors (see results). Thus, the POMS-BI
was not scored according to Lorr and McNair’s protocol. Instead, two subscales were
created, a Positive Mood Scale (PMS) using the six adjectives that loaded highest on the
first factor and lowest on the second factor and a Negative Mood Scale (NMS) using the
six adjectives that loaded highest on the second factor and lowest on the first factor.
Adjectives from the POMS-BI used to create the PMS were jolly, hill of pep, joyful,
active, lively, and cheerful. The six items from the POMS-BI used to create the NMS
were sluggish, exhausted, fatigued, tired, weary, and drowsy. Scores on the PMS and

NMS were simply the sum of all six items. Thus, a person’s score on the two scales could

49
range from 0 to 18, with higher scores indicating increased positive mood on the PMS and

increased negative mood on the NMS.
The Depression Adjective Checklist (DACL)

The DACL (Lubin, 1994), originally developed by Bernard Lubin in 1965, is a
multiple-item paper and pencil checklist measuring transient moods, feelings, or emotions
(Appendix G). Seven parallel forms allow repeated measurement of these factors. Five of
the seven forms were used in this study (Forms A, B, C, D, & G). These forms have been
shown to be highly inter-correlated (range .85 - .92). The DACL, typically used in
research settings, has well-demonstrated test-retest reliability and construct validity
(Lubin, 1994). Participants responded by checking the adjectives on the checklist that
describe how they felt at that moment. Examples of adjectives include wilted, safe,
gloomy, active, desolate, and strong. It took between one and three minutes to complete
each DACL.

Forms A, B, C, and D contain 22 negative adjectives and 10 positive adjectives.
Form G contains 22 negative adjectives and 12 positive adjectives. The manual provides
conversion tables and scoring forms (for both T scores and percentile scores) for state-
negative moods, state-positive moods, and state mood-total for each of the seven forms.
The manual not only provides normative data for adolescents and adults but also for males
and females. The state-mood total raw score is calculated as the sum of the number of
negative adjectives endorsed (i.e., state-negative mood) and the number of positive
adjectives that were not endorsed (i.e., 10 minus the state-positive mood for DACL A, B,

C, and D, and 12 minus the state positive mood for DACL-G) or State Total = 10 - State

50
Positive + State Negative. For purposes of this study, only the state mood total T-scores

were used in any statistical analyses using the DACL.
Procedure

Prior to the start of the experiment, the 78 participants were assigned randomly to
either the LRLR or RLRL condition with the constraint that each condition included an
equal number of right-handers and left-handers. Packets containing all forms to be used in
the study were prepared in advance and number-coded to ensure participant
confidentiality.

When the prospective participant entered the testing room, he was seated at a
small table across from the experimenter and given an Informed Consent Form to read and
sign. This form was also read aloud by the experimenter. Following this, the prospective
participant who agreed with the conditions and signed the consent form was given a
Medical History Questionnaire to complete. Prescreening measures were apparently
successfidl in eliminating inappropriate participants, as none of the 78 participants reported
that they had any histories of emotional distress or facial paralysis. Following this, all
participants completed the remaining three pro-test measures: 1) the Laterality
Questionnaire, 2) the Profile of Mood States-Bipolar (POMS-BI), and 3) the Depression
Adjective Checklist (DACL).

Next, the experimenter, while facing the participant, explained how the participant
was to perform the facial manipulations. The following instructions were read:

I want you to pay close attention to the following instructions. Don’t do anything

yet; just listen. I want you to pull back and raise the left/right side of your mouth

5 l
as much as you can, just like this [experimenter demonstrates by making the

mirror-image movement]. Now you try it. [After the participant successfillly

demonstrates the movement] That’s fine. When the experiment starts, I want you

to hold it in that position for 45 seconds until I say relax.
Ifnecessary, further instructions were given until the participant understood how to
perform the facial manipulation. The participant was then asked whether he understood
the procedure. Only 7 participants required additional instructions. Once it was clear that
the participant knew what he was required to do, the following instructions were read:

Now when I say “start,” I want you to pull back and raise the left/right side of

your mouth in the same way you just did and to hold that position until I say

“relax”. Remember to pull back and raise your mouth as much as you can. While

you’re pulling back and raising your mouth, I want you to breathe normally and to

look directly at me. I also want you to pay close attention to your mood, to how
you are feeling.

The side of initial contraction depended on a predetermined order to ensure equal
cells. After maintaining the contracted position for 45 seconds, the participant was told to
relax and to complete one version of the DACL. Following that, he performed the same
contraction on the opposite side of the face after which he was asked to complete another
version of the DACL. This procedure continued until he performed four contractions and
completed four versions of the DACL. After completion of the fourth facial contraction
and the fourth DACL, the participant completed another POMS-BI checklist. He then

was told that his participation in the study was complete. A debriefing period followed.

52
For the debriefing period, the participant was asked what he believed to be the

nature of the study. The experimenter then explained its actual purpose. The participant
was then asked whether he was feeling any emotional residue (either positive or negative)
fi'om his participation. None of the 78 participants indicated that they were feeling distress
following the completion of the last facial manipulation. The entire procedure took 45 to

60 minutes to complete.

RESULTS

The Lateralig Index Score

Of the light-handers, all reported using their right hand for writing. Their mean
laterality index score was 36.3 (S_D = 3.27). Of the left-handers, 37 of the 38 (97.4%)
reported using their left hand for writing. Their mean laterality index score was 16.03 (SD
= 7.224). Consistent with past studies, left-handers, as a group, were more heterogeneous
than light-handers (see Figure 2) as indexed by a Levene Test for Homogeneity of
Variances, Levene (1, 76) = 34.91, p < .0001. Across seven of the eight tasks, left-
handers were more heterogeneous than right-handers, the only exception being the
question about hand preference for writing a letter (see Table 2).
@Lsistency of Handedness

Consistency of handedness was determined using Peters’ decision rule (Peters,
1990; Peters & Servos, 1989; Ponton, 1987). Respondents who reported left-hand
preference for writing and six of seven other common unimanual tasks (hammer a nail,
throw a ball at a target, unscrew the lid of a jar, use a knife to cut bread, use a
toothbrush, hold a match while striking it, and hold a tennis racket) were classified as
consistent left-handers (CLHs). Participants with inconsistent hand preferences (ILHs)
were those who preferred the right hand for two or more of the eight items. Of the left-
handed sample, 18 (47.4%) were CLHs and 20 (52.6%) were ILHs. Using the same
decision rule for right-handers, 30 (75.0%) were CLHs and 10 (25.0%) were ILHs. This
classification yielded results consistent with those found in other studies using similar

criteria (e.g., Peters, 1990; Peters & Servos, 1989; Ponton, 1987).

53

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55
Table 2

Means Standard Deviations and Tests for the Homogeneity of Va_;ipnces for the Eigm

 

Items Comprising the Lateralig Index Score

Left-Handers Right-Handers value

lte_m m & Mean &

Write a letter 1.11 0.65 4.98 0.16 < .10
Hammer a nail 2.00 1.25 4.58 0.68 < .01
Throw a ball at a target 1.95 1.56 4.73 0.45 < .01
Unscrew the lid ofajar 2.63 1.48 3.98 1.10 < .01
Use knife to cut bread 2.18 1.43 4.55 0.68 < .01
Use toothbrush 1.92 1.30 4.33 0.83 < .01
Hold a match while striking it 1.97 1.24 4.48 0.68 < .01
Hold a tennis racket 2.26 1.59 4.70 0.61 < .01

56
POMS-BI Principle Components Analysis and Exploratory Factor Analysis

Because the POMS-BI manual did not provide statistical support (i.e., factor
analyses) for its proposed six-factor structure, a principle components analysis was
conducted to determine its factor structure.’ Because of the relatively small sample size of
the current study (N = 78) and the number of items in the POMS-BI (72 items), an
additional 40 female participants who had completed the POMS as part of another study
were included in the factor analysis.

A principle components analysis was first conducted on the POMS-BI in order to
obtain estimates of its initial factors. This analysis revealed 18 factors with eigenvalues
greater than one (Figure 3). Factors 1, 2, and 3 accounted for 27.0% , 8.8%, and 5.3% of
the variance, respectively. As Figure 2 demonstrates, there appear to be two or three
interpretable factors. Next, a principle components analysis was performed using the six
factor structure proposed by Lorr and McNair (1988). Only the subscale Agreeable had
an eigenvalue greater than one (Agreeable = 3.93), which accounted for 65.6% of the
variance (see Table 3). The correlations among the six subscales are presented in Table 4.
Given that only one subscale had an eigenvalue of greater than one and that the six
subscales appear to be highly correlated, there do not appear to be six distinct subscales,
contrary to Lorr and McNair’s suggestion. Therefore, a series of principle component
factor analyses was performed to find the most interpretable solution for testing the

current study’s hypotheses.

 

7 A11 factor analyses completed on the POMS-BI used a Varimax (orthogonal) solution in order to simplify
the interpretation of the factors.

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58
Table 3

Principle Components Analysis for the Six Subscales of the POMS-BI (n = 118)

 

 

Subscale Eigenvalue Percent of Variance
Agreeable 3.93 65.6

Clearheaded 0.74 12.3

Composed 0.52 8.7

Confident 0.35 5.8

Elated 0.25 4.2

Energetic 0.21 3.5

Table 4

Correlations Among Mood Scales for the POMS-BI (n = 118)

l 2 3 4 5 6
1 --

Agreeable 2 .51 --
Elated 3 .60 .68 --
Confident .64 .45 .68 --
Energetic .42 .57 .73 .61 --
Clearheaded .67 .48 .57 .65 .51 --
Mean 25.43 27.29 24.17 23.92 19.49 94.63
S. D. 5.44 4.89 5.51 4.99 8.23 5.72

59
A total of six principle components factor analyses were then computed using a

one-factor through six-factor solution. An upper limit of six factors was chosen because
this was the factor structure proposed by Lorr and McNair (1988). A two-factor solution
appeared most interpretable (see Table 5). Using this solution, adjectives describing a
negative mood state loaded highly on the first factor, and adjectives describing a positive
mood state loaded highly on the second factor. For both factors, items were selected that
loaded highest on that factor and least high on the other factor. Once items were selected,
reliability analyses and item-total statistics were conducted. Based on the item-total
statistic for the alpha if item deleted, adjectives were eliminated until the highest alpha
level was reached and the alpha if item deleted indicated that removing any one adjective
would lower the overall alpha level. Table 6 shows the inter-item coefficients, reliability
analysis, and item-total statistics for the Positive Mood Scale (PMS) using the six selected
items from the POMS-BI two-factor solution. Likewise, Table 7 shows the inter-item
coefficients, reliability analysis, and item-total statistics for the Negative Mood Scale
(NMS) using the six selected items fiom the two-factor solution. The PMS and the NMS
were used to test specific hypotheses where the POMS-BI was used as a dependent
measure.
Statistical Analyses

Several statistical analyses were selected to investigate the three hypotheses.
DACL t-scores were first analyzed using a 2 x 2 x 4, handedness (right or left) by order of
contraction (RLRL or LRLR) by time (DACL B, C, D, or G) repeated measures
ANOVA, with DACL-A as a covariate. DACL t-scores were then analyzed using a 2 x 2

x 2, handedness (light or left) by order (RLRL or LRLR) by face side (left face DACL

Table 5

Principle Components Analysis with Varimax Rotation for the POMS-BI Using a Two-

Egtor Solution (n = 118)

item

Lonely

Jolly

Full of Pep
Lively
Joyful
Active
Cheerfirl
Drowsy
Playful
Fatigued
Affectionate
Exhausted
Sluggish
Friendly
Agreeable
Kindly
Ready-to-go
Good-natured
Vigorous
Weary
Attentive
Tired
Confident
Powerfill
Mentally Alert
Eficient
Peacefill
Elated
Strong
Grouchy
Bold
Self-assured
Relaxed
Lighthearted
Weak
Serene
Forceful

POMS-BI Propoaed Loading 8

Elated
Elated
Energetic
Energetic
Elated
Energetic
Elated
Energetic
Elated
Energetic
Agreeable
Energetic
Energetic
Agreeable
Agreeable
Agreeable
Energetic
Agreeable
Energetic
Energetic
Clearheaded
Energetic
Confident
Confident
Clearheaded
Clearheaded
Composed
Elated
Confident
Agreeable
Confident
Confident
Composed
Elated
Confident
Composed
Confident

 

Factor 1
.80360
.79783
.77023
.74209
.73556
.71660
.68557
.66106
.65139
.63042
.62936
.62273
.61684
.60333
.59303
.59194
.59047
.55859
.55282
.54901
.54726
.52766
.50878
.50578
.48550
.46035
.45455
.44614
.43137
.42040
.40655
.40430
.38224
.36602
.32550
.32246
.27835

Factor 2
.08672
.10215
.18136
.15993
.16487
.16428
.02424
.17623
.10155
.25125
.11592
.27279
.36922
.20688
.15172
224480
.18173
.13120
.02086
.31845
.35748
.21004
.46817
.19461
.42996
.36179
.36043
.03020
.22496
.38304
.03635
.37569
.29422
.00981
.32215
.01012
.15244

a This column contains the mood state or factor that Lorr and McNair (1988) believed the item tapped.

Table 5 (cont’d).

m.
Businesslike
Uncertain
Unsure
Self-doubting
Uneasy
Discouraged
Mixed-up
Downhearted
Dejected
Muddled
Perplexed
Shaky

Sad

Jittery

Tense
Bewildered
Annoyed
Inadequate
Anxious
Calm
Nervous
Timid

Able to Concentrate
Anew
Lonely
Clearheaded
Confused
Mad
Untroubled
Gloomy
Dazed

Bad Tempered
Sympathetic
Furious
Composed

61

POMS-BI Propoaed Loading

Clearheaded
Confident
Confident
Confident
Composed
Elated
Clearheaded
Elated
Elated
Clearheaded
Clearheaded
Composed
Elated
Composed
Composed
Clearheaded
Agreeable
Confident
Composed
Composed
Composed
Confident
Clearheaded
Agreeable
Elated
Clearheaded
Clearheaded
Agreeable
Composed
Elated
Clearheaded
Agreeable
Agreeable
Agreeable
Composed

fem
.14404
.15340
.18825
.17951
.18699
.30835
.08035
.21135
.06253
.01495
.17812
.11793
.34286
.13675
.17158
.05184
.12555
.14828
.02529
.16994
.00608
.03152
.36187
.14673
.21740
.40165
.03287
.23653
.28178
.37178
.23839
.37064
.31967
.22017
.15500

M

.08011
.69659
.68881
.66524
.6601]
.65369
.65215
.63680
.63533
.63454
.6317]
.62512
.61697
.59042
.58928
.56399
.56186
.54723
.52410
.50787
.50447
.50447
.47793
.46561
.46312
.46010
.44787
.43912
.43745
.43323
.42997
.39601
.35215
.35215
.30364

Table 6

62

Later-item Coefficientfleliabilitv Analysis and Item-Total Statistics for the Pp_sitive

 

Mood Scale Created Using Selected Items from the POMS-BI Two-Factor Solution

(n=118)

Jofly
Pep
Joyful
Active
Lively
Cheerful
Mean

SD.

Inter-item Coefficients and Reliability Analysis

Jolly Pep Joyful Active Lively Cheerful
.57 --
.61 .62 --
.55 .57 .54 --
.58 .64 .62 .58 --
.53 .59 .68 .59 .65 --
1.44 1.19 1.78 1.86 1.63 1.81
.86 .88 .83 .88 .87 .77

 

Alpha = .90

Standardized item alpha = .90

63

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 6 (cont’d).
Item-Total Statistics
Item Scale Mean Scale Corrected Sguared Alpha
if Item Variance Item-Total Multiple if Item
Deleted if Item Correlation Correlation Deleted
Deleted
Cheerful 7.88 12.91 .67 .46 .89
Lively 8.06 11.99 .74 .55 .88
Joyfill 7.97 11.96 .75 .58 .87
Active 7.88 12.23 .69 .48 .88
Jolly 8.25 11.93 .73 .54 .88
Pep 8.56 11.75 .74 .56 .88

 

 

 

 

 

 

 

Table 7

64

I_n_ter-item Coefficients. Reliability Analysis Item-Total Statistics for the Negative Mood

Scale Created Using Selected Items from the POMS-BI Two-Factor Solution (n = 118)

Sluggish
Exhausted
Fatigued

Tired

Drowsy
Mean

SD.

Inter-item Coefficients and Reliability Analysis

.69

.66

.55

.71

.69

1.23

.94

Sluggish Exhausted

.74

.66

.61

.61

1.24

1.03

F atigued

.66

.61

.70

1.53

.95

Tired

.64

.55

1.90

Weary Drowsy

.63 --
1.03 1.28
.94 1.02

 

Alpha = .9167 Standardized item alpha = .9171

65

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 7 (cont’d).
Item-Total Statistics
Item Scale Mean Scale Corrected Squared Alpha
if Item Variance Item-Total Multiple if Item
Deleted if Item Correlation Correlation Deleted
Deleted
Sluggish 6.64 17.16 .77 .61 .90
Exhausted 6.68 16.96 .77 .61 .90
Fatigued 6.41 17.06 .81 .67 .90
Tired 6.00 17.33 .73 .55 .90
Weary 6.88 17.90 .73 .55 .91
Drowsy 6.59 17.23 .76 .60 .90

 

 

 

 

 

 

 

 

66
T-score composite, right face DACL T-score composite) repeated measures ANOVA,

with DACL-A as a covariate. POMS-BI NMS and PMS scores were analyzed using a
2 x 2, handedness by side of fourth facial manipulation AN COVA. For this analysis, the
first POMS-BI administration NMS and PMS scores were used as covariates. Lastly,
independent samples t-tests were used to examine handedness differences on pre-mood
measures.
Mood and Side of Face Contraction

ML

A repeated measures AN OVA revealed no main effect for order of facial
contraction [E (1, 72) < 1]. That is, there were no differences between participants in the
LRLR series and the RLRL. This was expected given that subjects were randomly
assigned to the two order conditions. The interaction between order and time was also
not significant [F(3, 219) = 1.67, p = .18]. Next, to create left and right DACL t-score
composites the t-scores of the two DACL completed after left facial manipulations were
collapsed together as were the two completed after right facial manipulations. Then
another repeated measures ANOVA was performed using these DACL T-score
composites. This analysis revealed no main effect for side of facial manipulation [F(1, 74)
< 1]. Given Schiff and Lamon’s (1993) observation that the effects of the manipulations
often did not occur until the third and fourth manipulations, another repeated measures
ANOVA was performed looking at only the last two facial manipulations; likewise, this

analysis proved to be insignificant [13 (1, 74) < 1].

67
BQM_S-B_I

Similarly, an ANCOVA with the first POMS-BI administration as a covariate
revealed no main effect for side of fourth manipulation as measured by the NMS E (1, 72)
<1]and the PMS E (l, 72) = 3.31, p = .07].

Mood and Handedness
DACL.

Contrary to the hypothesis that right-handers’ moods would change to a greater
degree than left-handers’ after both right- and left- facial manipulations, a repeated
measures ANOVA indicated no main effect for handedness E (1, 72) = 3.03, p = .09] nor
any interactions or significant differences between handedness and time E (3, 219) < 1].
When order of contraction (LRLR series vs. RLRL series) was taken into account, the
interaction between handedness, side of contraction, and time was also insignificant
E (3, 219) = 1.78, p = 0.15]. Thus, the results did not support the prediction that right-
handers would be more clearly lateralized than left-handers for the experience of emotion.
W

Likewise, using an ANCOVA with the first POMS-BI administration as a
covariate, there was no main effect for handedness on the NMS E (1, 72) < 1]. That is,
no significant differences were found between handedness and mood after the fourth facial
manipulation (irrespective of whether the fourth manipulation was a left or right
contraction), as measured by the NMS. Similarly, the main effect of handedness on the

PMS was insignificant E (1, 71) = 3.25, p = 0.08]. Although left handers had a slightly

68
higher PMS score after completing the fourth facial manipulation (M = 8.50, S_D = 4.50)

than right handers (M = 7.18, SE) = 4.68), this difference was not significant.

Taking side of fourth facial manipulation into account, there was no significant
interaction between handedness and side of fourth facial contraction as measured by the
NMS E (1, 72) < 1]. Likewise, PMS scores indicated no significant interaction between
handedness and side of fourth facial manipulation E (1, 72) = 2.13, p = 0.15].

Handedness and Pre-mood Measures
MEL

An independent t-test revealed no significant differences between right- and left-
handers on the pre-mood induction DACL [t (76) = -0.17, p = 0.87].

POMS-BI

Similarly, there were no significant differences between handedness and pre-mood
measures as measured by the POMS-BI PMS scale [t (76) = .07, p = .95] or the POMS-
BI NMS scale I! (76) = .09, p = .90].

Mood and Time of Ffljal Manipulation
RAIL.

Using a repeated measures ANOVA, a main effect was found for time E (3, 219)
= 8.76, p < 0.01]. Specifically, participants’ T-scores on the DACL increased over time
(across manipulations) indicating that the participants’ general sense of well-being

decreased significantly during the course of the experiment (see Figure 4).

69

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Supplemental Analyses

Consistent vs. Inconsistent Left-Handers

To determine whether the classification of left-handers into consistent and
inconsistent left-handed subgroups acted as a predictor variable for the effects of the facial
manipulations on mood, a repeated measures ANOVA with consistency of handedness as

a covariate was performed. The covariate was not significant [t (34) = 0.46, p = 0.65].

Difficulty of Maintaining Rig1_I - Vs. Left Fagial Contractions

 

Early in testing, many participants were observed to remark that one side of the
face was physically more difficult to hold than the other. Based on these observations,
two additional questions were included to be answered at the conclusion of the experiment
after all other measures were completed. The first question asked which side of the face
was physically more difficult to hold and the second asked which side was physically easier
to hold. Both questions used a 9-point Likert scale from 1 (Left Side) to 9 (Right Side),
with 5 (Same) as a midpoint. Sixty-one participants answered these two questions. Since
the two questions were highly correlated with one another (I; = 0.96), only the first
question was filrther analyzed.

This data were analyzed using a 2 x 2 x 4, handedness (right or left) by order of
contraction (RLRL or LRLR) by time (DACL B, C, D, or G) repeated measures
ANOVA, with difficulty level and DACL-A as covariates. Difficulty level, that is how
persons responded to the physical difflculty question, served as a significant covariate
[; (56) = 3.11, p < .01].

In light of this finding, it was predicted that changes in participant’s DACL scores

would be correlated with the reported level of difficulty for holding one side of the face.

7 1
To test this prediction, a ‘composite mood state change’ score was created to determine

the direction of change (e. g., increases in negative mood states after left or right
manipulations) and the degree or strength of change. The formula for change score was
the sum of the T-scores of the two DACLs completed after the right face manipulations
minus the sum of the T-scores of the two DACLs completed after the left face
manipulations. A positive score, therefore, meant that DACL T-scores were greater after
right face manipulations (indicative of a greater negative mood state after right faces);
conversely, a negative score meant that DACL T-scores were greater after left
manipulations. A bivariate correlation analysis was performed to examine the correlation
between the composite mood change score and how participants rated the physical
difficulty and ease of the facial manipulations. As can be seen in Table 8, these three
variables were significantly correlated suggesting that physical difficulty level of the face
and T-scores on the DACLs are related. That is, changes in the DACL may reflect either
the physical strain per se of holding the face or the emotions induced by the physical

difficulty (see Figures 5 and 6).

72
Table 8

Qorrelation Coefficients for Composite Mood Change Score and Repprted Physical
Difficulty or Ege of the Facial Manipulations

 

Composite Mood Difficulty Level of Base of the
Change Scores the Facial Facial Manipulation

mum

Comwsite Mood --
Change Scores

Difficulg Level of * .28 --
LEM

Manipulation

Ease ofFacial "‘ - .28 ** - .96 --
Manipulation

 

* p<.02
** p<.001

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DISCUSSION
The Failure to Replicate Schfiand Lamon’s Study

The prediction that left facial contractions would produce a dysphoric mood and
that right facial contractions would produce a euphoric mood was not borne out. That is,
the results of both the Depression Adjective Checklist and Profile of Mood States-Bipolar
indicate that left- and right-facial contractions did not produce difi'erent emotions. There
may be a number of possible explanations for these null effects.
Unilateral Facial Contractiopaand the Induction of Mood

One possibility that should be addressed immediately is that unilateral facial
contractions may not, in fact, induce emotional states at all. This explanation, however,
would seem premature given that (a) it is based on null results, (b) it does explain the
positive results in other studies (Schiff, Esses, & Lamon, 1992; Schiff & Lamon, 1989),
and (c) the current study used dependent measures different from those used in studies
reporting positive results. Finally, given that the current study followed Schiff and
Lamon’s (1989) method as outlined by them, it does not appear likely that its null results
are due to ineffective manipulation of the independent variables.9

Insensitivith the Current Study’s Measures of Mood

 

A second, more plausible, explanation is that the null findings are due, in part, to
the dependent measures’ inability to detect any true effects and, relatedly, to the

conservative nature of the statistical methods used. As just noted, the dependent measures

 

9 Recall that one of Schiff and Lamon’s (1993) arguments for Kop et al.’s (1991) failure to replicate Schiff
and Lamon’s (1989) study was that Kop et a1. did not strictly adhere to the mood induction procedure.

75

76
sharply differed from those used by Schifi’ and Lamon (1989). Whereas Schiff and Lamon

used self-report in two experiments and TAT cards in a third, the current study used two
different adjective checklists. Because of their high face validity, the accuracy of these
checklists to measure mood depends on participants’ ability and willingness to report these
changes. To the extent that participants were unwilling or unable to report mood changes,
the DACL and POMS-BI would be ineffective measures of any mood changes that
accompany facial manipulations. By contrast, projective tests like the TAT avoid many of
the difficulties created by indirect measures of mood of the sort used in the current study.

At first glance, this explanation of the null findings of the current study seems
plausible, but it is called into question when we look at the mood of participants across
manipulations. Recall that participants’ general sense of well-being decreased significantly
over the course of the experiment. If the null results were due to the DACL’s insensitivity
to mood changes, then it is hard to explain why an effect was still found for mood across
manipulations. If the measure was insensitive to mood changes arising fi'om unilateral
facial manipulations, it also should have been insensitive to mood changes across
manipulations.

The possibility that the null findings reflect the insensitivity of the dependent
measures is further called into question by Schiff and Lamon’s (1989) first two
experiments. In both, participants were asked to report any emotional experiences they
had while maintaining the contractions. This use of self—report limits the possibility that

the null findings were due to insensitivity of the measures, the high face validity not

77
withstanding. That is, Schiff and Lamon should have had similar difliculties asking

participants directly to report on their emotional experiences.
Over-Sampling of Moods

A third possibility is that the current study made too many measurements of mood,
that is, that having the participants complete a DACL after every manipulation might have
disrupted their effect on mood. This explanation, however, is unlikely for at least two
reasons. First, Schiff and Lamon (1989) took self-report measurements after every
manipulation in their second experiment and still found an effect. Thus, repeatedly asking
their participants to report on their mood did not disrupt the effects of the manipulation.
Second, foreseeing the potential hazard of taking measures after each manipulation, the
current study also included a second mood measure (the POMS-BI), which was given only
before the first manipulation and after the last manipulation (similar to Schiff and Lamon’s
third experiment). No effect was found for this measure either, which suggests that the

null findings are not due to over-sampling the effects of the manipulations.

Physical Difficulty of Facial Manipulations and Mood

 

Further analysis of the dependent measures in the current study suggests that they
may be more sensitive to the physical difficulty of contracting one side of the face relative
to the other than to the processes (presumably) measured by Schiff and Lamon (i.e., the
activation of sensory and motor pathways in the contralateral hemisphere). Recall that
difficulty level of the facial contraction served as a significant covariate and was correlated
with participant’s mood as measured by the DACL. This suggests that mood changes

reflect either the physical difficulty of holding the face in position or the emotions that

78
arise from that difficulty. Schiff and Lamon (1989) report that 66% of their participants

said that the left contraction was easier to perform. They also report that there was no
relation between ease of contractions and responses on the TAT. However, they do not
report what statistical analyses were performed to lead them to this conclusion or, indeed,
whether any statistical analyses were performed at all. Kop et al. (1991), however,
examined difficulty of contraction in their replication and found that when participants said
that one unilateral contraction was harder to perform than the other, mood changes (as
measured by evaluations of drawings) were evaluated more unfavorably after the harder
contraction. These results corroborate those found in the current study. Although the
current study’s results suggest that the physical difficulty of the contraction colors self-
reported mood, Kop et al.’s results suggest that it can also color one’s perceptions of the
evaluations of others (or at least one’s perception of favorableness of cartoon characters).
Thus, it is possible that the current study’s dependent measures were more sensitive to
physical difficulty than other processes and that the participants were responding to the
physical difficulty of the facial contractions.
Procedural Differences

The null effects could also have stemmed from differences between the two
studies, namely the placement of its dependent variables. Whereas Schiff and Lamon’s
(1989) third experiment used three TAT cards placed after the fourth manipulation, the
current study had participants complete a POMS-BI and a DACL before the first
manipulation, DACLs after each successive manipulation, and another POMS-BI after the

fourth manipulation. Thus, Schiff and Lamon’s (1989) method of measuring the effects of

79
the manipulation appears to be less rigorous on several levels. For instance, their study

assessed mood only after the fourth manipulation. The current study, on the other hand,
took mood measures after every facial contraction (something that we later will see calls
for different, more stringent statistical analyses). Schiff and Lamon also failed to include
pre-test mood measures to control for the possible effects that participants’ moods prior
to performing the manipulations may have had on subsequent manipulations. The current
study, on the other hand, took pre-test mood measures and mood measures after each
manipulation. It was found that pre-mood affected how a participant responded to the
subsequent mood measures, which suggests that before Schiff and Lamon’s participants
began the experiment, their moods may have affected their responses to the post-test
mood measures.
The Uae of Different Statistijll Analyses

Lastly, the null effects may reflect the use of different statistical analyses in the two
studies. If we assume that the mood induction technique is not robust and produces an
effect only after the third or fourth manipulation, as Schiff and Lamon (1993) later
suggested may be the case, then the current study’s inclusion of mood measures after
every manipulation in the statistical analysis may have washed out any effect that existed in
the first place. Although Schiff and Lamon (1989) said that, “the effects of these
contractions...appeared to be fairly robust” (p. 933), this statement may mislead on two
levels. First, Schiff and Lamon’s method of measuring the effect may not have allowed for
a true measurement of its robustness. The reason is that in their third experiment, they

measured the effects of only one of the four manipulations. Second, they reported that

80
over 33% of the responses to a target card were judged to be neutral in emotional tone.

These neutral responses were discarded fiom the analyses of left and right contractions,
whereas the current study included all responses in its statistical analyses. Furthermore, as
Kop et al. (1991) point out, although Schiff and Lamon reported that propositions had a
more positive tone after light than left contraction, this finding was based on only one of
nine t-tests that could have been performed. Kop et al. (1991) went on to say that it is
questionable whether this result would still be significant if Bonferroni-corrections had
been used. Lastly, because Schiff and Lamon failed to obtain pre-mood measures, there is
no way to determine whether negative, positive, or neutral stories told after the fourth
manipulation represent a change toward an increase or decrease in pre-mood emotion
states.

Until now, the focus has been largely on Schiff and Lamon’s third experiment
because this is the one that the authors called the most rigorous. The first two
experiments also deserve consideration because the procedures used were different fi'om
the third; thus, the criticisms of the third experiment may not necessarily apply to the first
two. The first two experiments also are procedurally more similar to the current study in
that measures were taken after each manipulation.

As mentioned earlier, the first two experiments employed self-report where
participants were to “pay attention to whatever emotional experiences they might have
while maintaining these contractions, to let them occur without judgment, and to report on
them when they were asked to relax” (Schiff and Lamon, p.926). The first experiment

was performed to explore the possibility of inducing emotions while maintaining unilateral

81
contractions of the facial muscles; no statistical analyses were performed. The second

experiment was performed in an effort to replicate the first study “in the laboratory to see
if the emotional changes would be detected under standardized experimental test
conditions and measurements” (p. 929). Both experiments reported finding support for
inducing emotions via the maintenance of unilateral contractions.

Statistipg Analysea Rm'aited

Several of the aforementioned possible explanations for the discrepancies in results
between the current study and Schiff and Lamon’s third experiment also apply to a
comparison of their first two experiments. It is possible, for instance, that the current
study’s independent measures were ineffective in measuring changes in mood because of
their high face validity. As already noted, however, this explanation does not explain why
mood did change significantly over time. Also, one would assume that Schiff and
Lamon’s use of self-report would have higher face validity than the adjective checklists
used in this study.

The different statistical analyses used in the two studies may provide a more
plausible explanation for the discrepant findings. Specifically, it appears that Schiff and
Lamon (1989) used less stringent statistical procedures to measure effects. Recall that in
their second experiment, Schiff and Lamon (1989) had participants report on their mood
after each manipulation. These reports were audiotaped and transcribed onto separate
pages, and order was randomized; therefore, there was a total of 120 mood reports from
30 participants. Two judges then “independently judged each report as having followed a

left or a right contraction, or as ‘unknown’ for those which they could not classify”

82
(p. 929). Fourteen reports were dropped because the judges classified them differently.

Of the remaining 106 reports, the judges agreed that 50 could not be classified. Of the 56
reports left, an equal number were predicted to have followed each facial contraction. The
accuracy of the judges’ predictions was then assessed for those 56 remaining reports. Of
the left face, 75% (21 out of 28), and of the right face, 71% (20 out of 28) of the
classifications were correct. Several questions arise from these data. First, how did the
judges classify the reports? Did they code for emotional statements, number of words
uttered, ratio of negative to positive statements, or did they use still other criteria?
Second, classifications could be made only on 56 of the 114 (53%) of the reports. Why
were the remaining 50 responses (47%) excluded from filrther analyses? If they had been
included, would this have washed out the effect? If all 120 responses had been included,
then only 75% of the responses (from the 53% that could be classified) were accurately
predicted to have occurred after left facial contractions. Similarly, from those 53% that
could be classified, judges were only able to predict that 71% of those occurred after right
facial manipulations. Thus, it appears that Schiff and Lamon (1989) somewhat
misrepresent the data when they state, “the judges were able to distinguish between
responses that followed a left face contraction from those that followed a right face
contraction with a high degree of reliability” (p. 930). It may be more accurate to say that
the judges were able to distinguish between responses that followed a left face contraction
fi'om those that followed a light face contraction with a high degree of reliability for those
56 (53%) reports that they were able to classify. In addition, there is no report of what

position in the series the classifiable responses came from. Did they come from a

83
particular subset of participants, or did each participant produce an equal number of

classifiable responses? Did they come from the first few manipulations in the series, fi'om
the concluding manipulations, or did placement in the series not matter?

In comparison to Schiff and Lamon’s statistical analyses, the current study’s
analyses were more rigorous. Pre-mood measures were taken to eliminate the effects of
participants’ pre-moods on subsequent manipulations, and all responses were included in
the analyses. Iffacial manipulations do not always produce classifiable mood reports, it
suggests that inclusion of all mood reports in the analyses may have washed out the efl’ect
if any existed.

Conclusions

There may be at least two plausible explanations for the null results of the current
study. The first is differences in methodology, namely the placement of the dependent
measures and the subsequent statistical analyses performed. That is, given that Schiff and
Lamon (1989) were able to find classifiable responses only 53% of the time, the current
study’s inclusion of all responses may have washed out an effect if any existed. Second,
the current study used dependent measures that may have been more sensitive to the
efl‘ects of physical difficulty on mood rather than to processes that Schiff and Lamon
measured (assuming more than one process occurred).

flandedness Differences

Given the failure to support Schiff and Lamon’s mood induction technique, it is

difi’lcult to say what this might mean in terms of the valence hypothesis for the experience

of emotion. For instance, the failure to find differences between side of facial

84
manipulation and mood may cast doubt on the valence hypothesis for the experience of

emotion, or it may simply mean that the current study failed to detect any differences for
any of the reasons discussed earlier. For the same reason, it is difficult to understand the
lack of support for the prediction that right-handed males would be more clearly
lateralized than left-handers. The question still remains whether the null results for
handedness mean that the neuropsychological systems for the experience of emotion are
the same in right- and left-handers or whether differences do exist but are masked by the
insensitivity of the procedures and statistical measures to detect real differences.

Because of the null effects, we cannot examine the valence hypothesis as it relates
to handedness and the experience of emotion. We can, however, examine the relation of
handedness to participants’ moods at the start of the experiment as well as to changes in
mood over time irrespective of side of facial manipulation. This examination, too,
indicated no significant differences between right- and left-handers’ pre—induction moods.
Recall that the literature suggests a weak relation between handedness and measures of
emotionality — sometimes it is there, sometimes it is not — so it is not surprising that
this study failed to achieve any differences. Focusing on handedness and mood across all
manipulations, no handedness differences were found. However, with a larger sample size
the results suggest that handedness differences would become significant. This was
indicated by both dependent variables. The problem, however, is that differences go in the
wrong direction, namely that left-handers’ mood states are less negative (more positive)
across manipulations. How could these differences be explained had they been significant?

One possibility is that the increased bilaterality of left-handers makes them less susceptible

85
to the negative effects of the manipulations regardless of side of manipulation. The results

of the POMS-BI, however, suggests that there are no differences between handedness and
negative mood states. The difference approached significance with left-handers showing
slightly higher positive mood states after the fourth manipulation. Again, there is no
obvious explanation for these findings. In addition, the difference in mood is again in the
opposite direction of the one predicted (recall that when differences have been found
between right- and left-handers, left-handers showed more negative mood states).
General Conclusions and Future Directiorys

Given the several factors that may have contributed to this study’s null findings, it
is not safe to draw any conclusions about Schiff and Lamon’s (1989) mood induction
procedure as it relates to the valence hypothesis or to handedness and the
neuropsychology of the experience of emotion. The current results do suggest that the
manipulations produce subtle effects that may not occur all of the time and that are
difficult to detect when they do occur. It still remains peculiar that three of the ten
participants in Schiff and Lamon’s (1989) first experiment began to weep. Although, none
of the 78 participants in the present study showed such reactions, this suggests that the
effects of the manipulations have the potential to be quite dramatic. It is also noteworthy
that Schiff and his colleagues are the only ones to demonstrate successfully the effects of
their mood induction across different domains (self-report, responses made to TAT cards,
chimeric faces, and social cognitive judgments). Schiff himself (personal communication,
September 12, 1996) recognizes the difficulty in inducing mood via their technique:

“emotion reports are hard to get...at the best times undergraduates are guarded or poor at

86
reporting on what they are feeling.” If so, then the current study also suggests that

undergraduates are poor at recognizing their emotions given that they were provided with
a list of adjectives related to mood that they could choose fi'om. Ifthis is, indeed, the
case, it would not explain why differences in mood were achieved over time. This
suggests that the participants were able to recognize and report on their mood on some
level (though, as discussed earlier, it may have been on a more physical level). Again, this
points to the elusiveness of this mood induction technique.

Although the current study’s failure to replicate Schiff and Lamon’s findings does
not allow us to examine the valence hypothesis for the experience of emotion or its
relation to handedness, it does contribute to the literature in several other domains, namely
in the areas of mood induction techniques and self-report measures of mood.

The current study sheds light on the limitations of Schiff and Lamon’s mood
induction technique and points to areas to examine in the future. Clearly the efl’ect was
not so robust as described in Schiff and Lamon’s first experiment. Initially it was hoped
that their technique could be used one day to treat various clinical populations. One could
imagine a depressed client raising the right side of the face to temporarily lift mood.
Although these hopes are not erased by the current study’s null findings, this study does
suggest that the effects of the technique might not be as robust as was once hoped and
that there are still many unanswered questions about the factors that enhance or inhibit the
effect. It is not until more information is collected about these factors that we can begin
to focus more closely on the method’s applied functions. Perhaps by studying specific

clinical populations (i.e., individuals with major depression) we can determine whether

87
such individuals have stronger responses to the manipulations, greater shifts fi'om one

manipulation to the next, or appear different in some other way fiom other clinical or non-
clinical populations. It may be that in the future we could create a laterality index score
for the experience of emotion (similar to the handedness laterality index scores that are
tabulated using performance scores on motor tasks). In turn, this score might allow us to
meaningfully subclassify persons according to their laterality score in a way that has both
diagnosis and treatment implications. Before these issues are examined, however,
attention must be paid to the conditions under which the mood manipulation proves
effective or ineffective. In short, we must first get a clearer picture of the limitations of
this mood induction technique before its applications can be examined.

Despite its potential limitations, Schiff and Lamon’s method of mood induction
still appears to be one that may eventually offer a way to better understand the
lateralization of the experience of emotion. Recall that it offers the single most “pure”
measure of the experience of emotion; to the extent that other methods also measure the
perception or experience of emotion, they cannot provide information about lateralization
of the experience of emotion. Given that the unilateral contraction of facial muscles may
not be enough to produce strong and reliable effects, it may be necessary to employ other
muscle groups as well. Schiff and Truchon (1993) have demonstrated that unilateral
contraction of hand muscles can affect perceptions of chimeric and neutral faces. Perhaps
a combination of hand and face contractions, along with foot contractions, would enhance
the effects of the mood induction. As mentioned earlier, it is only when we better

understand the conditions under which this mood induction occurs and what it means in

88
terms of the valence hypothesis for the experience of emotion that we can begin to

effectively examine its usefulness in clinical settings.

In addition to the information the current study provides about the limitations of
Schifl‘ and Lamon’s mood induction technique, it also underscores the many difficulties in
using self-report measures of mood. First, it demonstrates that measures of mood state do
not always measure what they intend or report to measure. The POMS-BI was believed
to measure six underlying dimension of mood (and initially included for that reason),
whereas the current results indicate that it measures just two dimensions, namely positive
and negative mood states. Thus, to the extent that one seeks to examine changes in and
interactions between different mood dimensions, it is crucial that one first determine
whether the measure chosen is one that is in fact able to measure these dimensions.
Unfortunately for the current study, one of the measures lacked the ability to discriminate
between the six mood states as reported by Lorr and McNair (1988). This finding is
corroborated by Lorr and Wunderlich (1988), who also found the POMS-BI to measure
two higher-order dimensions (positive and negative affect). Second, the current study
shows that certain persons, when reporting their mood, may be responding in a “physical”
manner. That is, they may describe their moods in terms of their “physical” well-being
rather than their “emotional well-being” (i.e., feeling tired versus feeling sad). If this is the
case, then to the extent that a chosen measure emphasizes the measurement of “physical
well-being,” the effects of the manipulation independent of those related to the difficulty of
holding the face may be obscured. This finding has important implications for future
replication attempts. To elaborate, it will be necessary to find those instruments that

provide the “purest” measure of emotional well-being so that we can more accurately

89
examine mood changes that currently appear to be masked by the physical effects of the

manipulation. Related to this point, to the extent that reports of physical symptoms reflect
participants’ reluctance to report other changes in mood (i.e., their guard is up), then it
will be important to determine how to create an environment conducive to producing
accurate mood reports. It is only then that we can more effectively examine the valence

hypothesis for the experience of emotion.

APPENDICES

APPENDIX A

90
Appendix A

INFORMED CONSENT FORM

This is a study of the effects of facial muscle contractions on mood in normal,
healthy people. It is a “normative study”, which means that we don’t know how normal,
healthy people will respond, and we want you to help us find out. There are no right or
wrong ways to respond. For example, you may feel a change in your mood or you may
feel no change at all. Either response is possible, and that is why there is no right or
wrong way to respond. The study will take about one hour to complete. You will receive
one hour of research credit for participating.

Your record will be kept completely confidential. To ensure this, you will be
assigned a participant number, which will be the only way to identify you in any reports
about the study. Only the experimenter will have access to files and lists that can be used
to link a name with a participant number. Any publications resulting fi'om this work will
not identify you by name or in any way that would allow your identity to be discovered.

For this study, you will be asked to complete several tasks.

1. On the Participant Identification Form, you will be asked to write your name.
This is the only form that can identify you by name and link you to the participant
identification number that has been assigned to you. Only the experimenter and his
designates will have access to your file. To ensure confidentiality, all other documents you
fill out will have only your participant identification number.

2. On the Medical History Questionnaire, you will be asked whether you have a
history (either past or present) of clinical depression, bipolar episodes, substance abuse,
anxiety disorders, hypertension, and facial paralysis. This form is a screening measure that
will be used to identify and exclude individuals with any of the above-mentioned histories.
For this study, such individuals cannot be included.

3. On the Personal Information and Background Questionnaire, you will be asked
to provide your age, sex, ethnicity/race, years of education, and academic major.

4. On the Laterality Questionnaire, you will be asked to identify which hand you
prefer to use for a variety of common tasks. You will be asked whether anyone (including
yourself) has tried to change your hand preference.

5. On the Profile of Mood States-Bipolar form, you will be asked to check off
adjectives on a list that describe how you feel at a given time.

91

6. After completing these questionnaires, you will be asked to perform four facial
manipulations, specifically, to move the lower part of your face into a certain position and
then to hold that position for 45 seconds.

7. After each facial manipulation, you will be asked to complete another mood
check list. For this measure you again will be asked to check off adjectives describing
how you feel.

8. Lastly, you will be asked to complete a different Profile of Mood State-Bipolar
checklist.

A debriefing period will follow your participation in the experiment. You will
receive one hour of research credit for your participation. You have the right to
discontinue your participation at any time and for any reason, and to do so without
explanation or penalty. There is also an alternative method of earning extra course credit
if you do not wish to participate in this or other experiments. If you wish to seek this
alternative, speak with your Introductory Psychology professor for specifics. The
assignment may vary fi'om professor to professor, but it is usually to write a short paper.

If you would like filrther information regarding your rights as a research
participant, you may contact the Office of the UCRlI-IS at Michigan State University by
telephoning (517) 3 55-2180.

After the entire study is completed, if you have any questions or if you want a
written summary of the general results, you may contact the investigators at their
university offices.

 

I have read this consent form, I understand the conditions, and I voluntarily agree to
participate in this study.

 

Participant’s Signature Date

 

Investigator’s Signature Date

APPENDIX B

Appendix B

PARTICIPANT IDENTIFICATION FORM

This is the only form that can identify you by name and can link you to the participant
identification number that has been assigned to you. Only the investigator and his
designates will have access to this form. To ensure confidentiality, all other documents
you fill out will have only your participant identification number.

Please print your full name.

Participant Name: Identification Number:

 

 

92

APPENDIX C

Appendix C

MEDICAL HISTORY QUESTIONNAIRE

Please check whether you have, or at some time in the past have had, any of the following
conditions:

CURRENT PAST

Yes No Yes N 0
Major Depression _ _ __ _
Bipolar Disorder __ _ _ _
Generalized Anxiety _ _ _ _

Panic Disorder

Post Traumatic Stress Disorder
Substance Abuse
Schizophrenia

Other Emotional Disorders:

 

Hypertension
Have you ever suffered from any

type of facial paralysis?

If yes, please describe:

 

 

 

 

 

93

APPENDIX D

Appendix D

PERSONAL INFORMATION AND BACKGROUND QUESTIONNAIRE

. What is your age?
. Are you? Male: _ Female: _

. What year in school are you in now?

 

. What is your academic major?

 

. Which ethnic/race category best fits you?

Caucasian: _ Asian: _
Afiican-American: __ Hispanic: _
Native American:. _ Other: _ Define:

 

94

APPENDIX E

Appendix E

LATERALITY QUESTIONNAIRE
A. General Handedness
Circle the description that best applies to you:
a. Strongly left-handed
b. Moderately left-handed
c. Ambidextrous (either-handed)
d. Moderately right-handed

e. Strongly right-handed

Circle the picture which best depicts how you hold a pencil when writing.

Left-Handed Writers Right-Handed Writers

 

95

96
B. Hand Use for Specific Tasks

For each of the tasks listed below, check the column that corresponds to the hand you
would use to perform that task.

Always Usually Usually Always
Left Left Both Right Right
1 2 3 4 5
Hand Use
1.Write a letter _ _ _ _ _
2. Hammer a nail

3. Throw a ball at a target
4. Unscrew lid of a jar

5. Use knife to cut bread
6. Use tooth brush __ _ _ _ _
7. Hold a match while striking it _

8. Hold a tennis racket

Has anyone (including yourself) tried to change what
hand you use for any of the tasks listed above

or for any other tasks? _
No Yes

If yes, please identify the task(s) and describe the circumstances.

 

 

 

 

 

APPENDIX F

Appendix F
Profile of Mood States-Bipolar (POMS-BI)

Below are words that describe feelings and moods people have. Please read EVERY word carefully.
Then circle ONE number which best describes how you are feeling RIGHT NOW AT THE PRESENT
MOMENT. Suppose the word is happy. Mark the one answer closest to how you are feeling RIGHT
NOW AT THE PRESENT MOMENT.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0 = MUCHUNLIKETHIS

l = SLIGHTLYUNLIKETHIS

2 = SLIGHTLYLIKETHIS

3 = MUCHLIKETHIS
Composed 1234 Vigorous 1234 Same 1234 Ready-top 1234
Any 1234 Dejected 1234 sodternpored 1234 Disootnpod 1234
Cheerful 1234 Kindly 1234 Joyful 1234 Good-nausea 1234
Weak 1234 Fatigued 1234 Self-doubting 1234 Weary 1234
Teme 1234 Bold 1234 Shaky 1234 Confident 1234
Court-ed 1234 Efficient 1234 Perplexed 1234 Businesslike 1234
Lively 1234 Peaceful 1234 Active 1234 Relaxed 1234
Sad 1234 Furious 1234 Downheuted 1234 Annoyed 1234
Friendly 1234 Lighthearted 1234 Ageeable 1234 Elated 1234
Tired 1234.Unsure 1234 Sluggish 1234 lnodequrte 1234
soon; 1234 Jittery 1234 Forceful 1234 Uneasy 1234
Cle-headed 1234 Bewildered 1234 AbletoConcentrate 1234 Dazed 1234
Untreubled 1234 Energetic 1234 Calm 1234 Fullorpep 1234
Crotrdry 1234 Lonely 1234 Mad 1234 Gloomy 1234
Playful 12 3 4 Sympathetic 12 3 4 lolly 12 3 4 Affectionate 12 3 4
Timid 1234 Exhausted 1234 Uncertain 1234 Drowsy 1234
Nervous 1234 Powerful 1234 Anxious 1234 Self-assured 1234
Mixed-up 1234 Attentive 1234 Muddled 1234 Mentallyalert 1234

 

 

 

 

 

 

 

 

 

 

97

APPENDIX G

Appendix G

ST-DACL

Form A

Directions: Below you will find some words that describe different kinds of moods and feelings.
Check the words that describe how you feel right now - at this moment. Some of the words may
sound alike, but we want you to check all of the words that describe your feelings. Work rapidly and
check all of the words that describe how you feel right now. Ifyou need to change an answer, clearly
erase the incorrect answer.

 

 

List A

O l. Wilted O 17. Strong
0 2. Safe 0 18. Tortured
O 3. Miserable O 19.Listless
O 4. Gloomy O 20. Sunny

0 5. Dull O 21. Destroyed
O 6. Lively O 22. Wretched
O 7. Low-spirited O 23. Broken
O 8. Sad O 24. Lighthearted
O 9. Unwanted O 25. Criticized
O 10. Fine 0 26. Grieved
O 11. Brokenhearted O 27. Dreamy
O 12. Downcast O 28. Hopeless
O 13. Enthusiastic O 29. Oppressed
O 14. Failure 0 30. Joyous
O 15.Afflicted O 31.Weary

O 16. Active 0 32. Droopy

 

 

98

99

ST-DACL

Form B

Directions: Below you will find some words that describe different kinds of moods and feelings.
Check the words that describe how you feel right now - at this moment. Some of the words may
sound alike, but we want you to check all of the words that describe your feelings. Work rapidly and
check all of the words that describe how you feel right now. Ifyou need to change an answer, clearly
erase the incorrect answer.

 

 

List B
O 1. Downhearted O 17. Clean
0 2. Lively O 18. Dispirited
O 3. Unfeeling O 19. Moody
O 4. Alone 0 20. Pleased
O 5. Unhappy O 21.Dead
O 6. Alive 0 22. Sorrowful
O 7. Terrible 0 23. Bleak
O 8. Poor O 24. Light
0 9. Forlorn O 25. Morbid
O 10. Alert 0 26. Heavyhearted
O 11. Exhausted O 27. Easygoing
O 12.Heartsick O 28. Gray
0 13.Blight O 29. Melancholy
O 14. Glum O 30. Hopeful
O 15. Desolate O 31. Mashed
O 16. Composed O 32. Unlucky

 

 

ST-DACL

Form C

Directions: Below you will find some words that describe different kinds of moods and feelings.
Check the words that describe how you feel right now - at this moment. Some of the words may
sound alike, but we want you to check all of the words that describe your feelings. Work rapidly and
check all of the words that describe how you feel right now. Ifyou need to change an answer, clearly

erase the incorrect answer.

100

 

 

fl

Cheerless
Animated
Blue

Lost
Dejected
Healthy
Discouraged

Bad

PESP‘MPP’N

Despondent
10. Free

1 l. Despairing
12. Uneasy

1 3 . Peaceful

14. Grim

15. Distressed
16. Whole

OOOOOOOOOOOOOOOO

List C

OOOOOOOOOOOOOOOO

l7. Buoyant
18. Tormented
19. Weak

20. Optimistic
21 . Low

22. Deserted
23. Burdened
24. Wonderfirl
25. Crushed
26. Somber
27. Interested
28. Joyless
29. Crestfallen
30. Lucky

3 1. Chained

32. Pessimistic

 

 

101

ST-DACL

Form D

Directions: Below you will find some words that describe different kinds of moods and feelings.
Check the words that describe how you feel right now - at this moment. Some of the words may
sound alike, but we want you to check all of the words that describe your feelings. Work rapidly and
check all of the words that describe how you feel right now. Ifyou need to change an answer, clearly
erase the incorrect answer.

 

 

List D
O 1. Depressed O 17. Fit
0 2. Elated O 18. Lonesome
O 3. Awfill O 19.Unloved
O 4. Lifeless O 20. Glad
O 5. Griefstricken O 21. Grave
O 6. Inspired O 22. Sunk
O 7. Woefirl O 23. Shot
O 8. Lonely O 24. Merry
O 9. Suffering O 25. Wasted
O 10. Mellow O 26. Washed out
0 11.Drooping O 27. Clear
0 12. Rejected O 28. Gruesome
O 13. Fortunate O 29. Tired
O 14.Dreary O 30. High
0 15. Lousy O 31.Worse
O 16. Good 0 32.Drained

 

 

102

ST-DACL

Form G

Directions: Below you will find some words that describe different kinds of moods and feelings.
Check the words that describe how you feel right now - at this moment. Some of the words may
sound alike, but we want you to check all of the words that describe your feelings. Work rapidly and
check all of the words that describe how you feel right now. Ifyou need to change an answer, clearly
erase the incorrect answer.

 

 

OOOOOOOOOOOOOOOOO

List G

1. Heartsick 18. Enthusiastic
2. Healthy 19. Bleak

3. Sad 20. Griefstricken
4. Afflicted 21. Eager

5. Lonesome 22. Drained

6. Fine 23. Desolate
7. Alone 24.Miserable
8. Gloomy 25. Merry

9. Depressed 26. Dull

10. Alive 27. Melancholy

1 1. Heavyhearted
12. Failure

13 .Glad

14. Despondent
15. Sunk

16. Optimistic

17. Jovial

OOOOOOOOOOOOOOOOO

28. Interested
29. Unwanted
30. Gruesome
3 1. Whole

32. Oppressed
33. Lifeless
34.Elated

 

 

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