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This is to certify that the

dissertation entitled

SPEECH AND NONSPEECH MOTOR BEHAVIOR IN
SCHOOL-AGED STUTTERERS AND NONSTUTTERERS

presented by

Jay Richard Greiner

has been accepted towards fulfillment
of the requirements for

 

Ph. D. degree in Psychology

 

/ Maj pudfessor I
Hiram E. itzgerald
Date 12/ 12/ 85

 

MS U is an Affirmative Action/Equal Opportunity Institution

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SPEECH AND NONSPEECH MOTOR
BEHAVIOR IN SCHOOL-AGED
STUTTERERS AND NONSTUTTERERS
by

Jay Richard Greiner

A DISSERTATION

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

DOCTOR OF PHILOSOPHY
Department of Psychology

1986

(Q1986

JAY RICHARD GREINER

All Rights Reserved

ABSTRACT
SPEECH AND NONSPEECH MOTOR
BEHAVIOR 1N SCHOOL-AGED
STUTTERERS AND NONSTUTTERERS
By

Jay R. Greiner

Theoretical and empirical research suggest that normal,
developmental disfluency and stuttering have common mechanisms but
differ on the degree of lateralized speech and lateralized motor
disorganization and emotional stress associated with social speaking
situations. The present study compares lateralization of speech and
nonspeech motor function in 60 right-handed male children, 30
stutterers and 30 nonstutterers. Measures included: (1) evaluation
of language processing and production; (2) bimanual handwriting of
verbal symbols; (3) concurrent bimanual handwriting and speech;
(4) concurrent bimanual handwriting and lateralized allocation of
attention; (5) concurrent unimanual sequential finger tapping and
speech; and (6) emotional stress questionnaire.

Subjects were included in the current study only if they
achieved appropriate age percentile ranks on the language processing
and production measures. Bimanual handwriting results suggest that
right-handed stutterers, compared to nonstutterers, have poorer left

hand performance and greater frequency of left hand and right hand
i

mirror reversals during bimanual writing. The results suggest
further, that stutterers and nonstutterers younger than age 9 lack
full left hemisphere motor lead control, with stutterers younger than
age 9 having the least left hemisphere motor lead control during
bimanual tasks. Left hemisphere inhibition of right hemisphere
activity occurs in nonstutterers after age 9. In stutterers, lack
of left hemisphere motor lead control continues from age 6 to 16.

Concurrent sequential tapping results suggest that stutterers
have more finger sequencing errors than nonstutterers as well as more
within-word fragmentation during spontaneous speech. Both hands
produced sequencing. errors in stutterers and nonstutterers
suggesting interhemispheric processing. Compared to nonstutterers,
stutterers had fewer correct tapping sequences and higher error
rates. Tapping errors increased with age in stutterers, and
decreased with age in nonstutterers. These results suggest that in
normal speaking children,, the left hemisphere is the active
hemisphere in temporal sequencing and regulation, whereas in
childhood stutterers, the right hemisphere is more involved and
involved in an inefficient way.

Emotional stress questionnaire results suggest that childhood
stutterers have higher interpersonal stress that nonstutterers.
Dimensions derived from the questionnaire suggest that childhood
stutterers have lower self-esteem and confidence, higher audience

sensitivity, and less interest in social interaction than

nonstutterers.
ii

This work is dedicated to Marti.

iii

ACKNOWLEDGMENTS

This research was completed with the advice and insight of
faculty and fellow students at Michigan State University and I am
deeply grateful for their assistance and cooperation. I wish to
acknowledge each of the following individuals:

Hiram E. Fitzgerald, chairperson of the Dissertation committee
and major adviser throughout my graduate career at Michigan State
University. I am particularly grateful for his time and patient
guidance from conception through completion of this research and for
his interest in integration of psychology with other human science
disciplines;

Paul A. Cooke, Lauren J. Harris, and Raymond W. Frankmann, my
other committee members, for assistance in conceiving and completing
this research with children, particularly for insight into speech and
language disorders, neuropsychology of language and statistical
analysis;

David Daly and Aaron Smith of The University of Michigan and
other faculty members of the supportive academic community at
Michigan State University, for their time and cooperation in
developing my understanding of neuropsychology;

The Lansing School District and speech therapists of the
Mid-Michigan area for their full cooperation and interest in research
of speech and nonspeech motor development in school-aged stutterers

and normal-speaking children;

iv

Jeff Bell, Karen Cornwell, Dan Stultz and Scott Friedman for
their intelligent and concerned input during the organization and
analysis of this research;

Ivy Tetenbaum, Kathy and Muhammed Symbal, Terri Kummer and
Mary Cote for their assistance in scoring the research data;

Supportive and caring friends and family.

This research was supported in part by a grant from the Spencer

Foundation.

TABLE OF CONTENTS

Page

LIST OF TABLES... ...... ............. . . . . .. . ......... . Vill
INTRODUCTION............. ...... . .. . . .. .. ......... . 1
LITERATURE REVIEW ............................................. 4

Stuttering and hemispheric contribution to speech

organization............ ....... ..................... ..... 4

Development of hemispheric contribution to speech

organization ............................. .. ............ .. 11

Developmental mechanisms of speech and nonspeech motor

coordination.. ............. ...................... ........ 13

The development of left hemisphere specialization........ 13
The development of interhemispheric transfer and inhibition 14
Development of hemispheric control of the lateral

gradient of attention....................... ............. 18
Speech organization and develOpmental disfluency ......... 21
Differentiation of developmental and pathological
disfluency............................................... 22
Components of disfluency ............ ... .................. 24
Diagnostic components of speech disorganization

in children...... ..... ................................... 27
Speech organization and attentional development.......... 30

General procedure and hypotheses.................. ....... 33

vi

Table of Contents (Continued)

Page
METHOD ............................. . ...... ..... ......... ...... 34
Subjects................................................. 34
Procedure ................................................ 34
Data analysis ........... . ..... . ..... ..................... 42
RESULTS ......................... . ..... ...... ..... .... ......... 44
Bimanual handwriting ....................... .............. 44
Unimanual sequential tapping ............................ . 64
Speech fluency..: ...... . ..... . ........... ..... ........... 73
Speech disfluencies during tapping ....................... 76
Emotional stress questionnaire ................. . ....... .. 89
DISCUSSION ...... . ............................. . ........... .... 96
APPENDICES .................. . ................. ................ 114
A. Project description letter, research informed consent
form and individual information form................. 115
B. Bimanual handwriting stimuli; digits from 1 to 12
and letters from A through L ...... ................... 120
C. Emotional stress questionnaire ..................... .. 123
REFERENCES. L ............. . .................................... 127

vii

Table

10.

11.

12.

LIST OF TABLES

Leuden square experimental design for unimanual
sequential tapping task

Bimanual handwriting organization in three age groups of
stutterers and nonstutterers with no speech or

lateralized attending: task 1............................
Bimanual handwriting organization in three age groups of

stutterers and nonstutterers with no speech or
lateralized attending (Replication): task 2..............

Bimanual handwriting organization in three age groups of
stutterers and nonstutterers with concurrent speech:
task 3

Bimanual handwriting organization in three age groups of

stutterers and nonstutterers with lateralized attending
to the left hand: task 4

Bimanual handwriting organization in three age groups of
stutterers and nonstutterers with lateralized attending
to the right hand: task SOOOOOOOOOOOOOOOOOO......OOOOOOOO

Total reversals in bimanual handwriting in three age groups

of stutterers and nonstutterers across five tasks........

Reversals in handwriting in three age groups of stutterers
and nonstutterers with no speech or lateralized attending:
task 1

0.000.0.........OOOOOCOOOOOOOOOOOO......COOOOOOOOOO

Reversals in handwriting in three age groups of stutterers
and nonstutterers with no speech or lateralized attending
(Replication): task 2.O.....IO.........OOOOOOOOOOOOOOOOOO
Reversals in handwriting in three age groups of stutterers
and nonstutterers with concurrent speech: task 3

Reversals in handwriting in three age groups of stutterers
and nonstutterers with lateralized attending to the left
hand: task 4

Reversals in handwriting in three age groups of stutterers

and nonstutterers with lateralized attending to the right
hand: task 5

viii

Page

40

45

47

48

49

51

54

55

57

58

6O

11

List of Tables (Continued)

Table Page

13. Mean sequential tapping rates for age and hand—used-for-
tapping main effeCtSOO....0.0.........OOOOOOIOOOOOOOO...O 66

14. Mean sequential tapping rates for task main effect and
trial block x task interaction........................... 67

15. Mean correct tapping sequences for speech group, age and
hand-used-for-tapping main effects....................... 68

16. Mean correct tapping sequences for task main effect and
trial block x task interaction........................... 70

17. Mean tapping error rates for speech group main effect and
speech group x age interaction ....... .................... 71

18. Percent mean pretest speech fluency in three age groups of
stutterers and nonstutterers during three speech tasks... 74

19. Percent mean speech fluency during tapping for speech
group, age, trial block and task main effects..... ..... .. 75

20. Percent mean speech fluency during tapping for task
x speech group and task x speech group x age x
hand—used—for—tapping interactions....................... 77
21. Mean audible prolongation scores for speech group and task
main effects and speech group x task interaction......... 79

22. Mean tense surge scores for speech group and task main
effect and speech group x task interaction............... 80

23. Mean part-word repetition scores for speech group and task
main effects and speech group x task and speech group x
hand-used-for—tapping interactions....................... 82

24. Mean whole—word repetition scores for task main effect and
speech group x task x hand-used-for—tapping interactions. 83

25. Mean phrase repetition scores for the age x hand—used—for-
tapping interaction...................................... 85

26. Mean revision scores for the task main effect and task x
hand-USGd-fOP-tapping inteI'aCtiOn. o o o o o o o o o o o o o o o o o o o o o o o 86

ix

27.

28.

29.

List of Tables (Continued)

Means and ANOVA comparing stutterers and nonstutterers on
emotional stress questionnaire total score...............

Means and ANOVA comparing stutterers and nonstutterers on
three dimensions of the emotional stress questionnaire
as revealed by confirmatory factor analysis..............

Emotional stress questionnaire items and associated
loading factors ranked in order from most to least
reliable measures of three dimensions for stutterers

and nonstutterers........................................

9O

91

93

INTRODUCTION

There is considerable agreement that young children as compared
to older children are more likely to have speech organization that is
perceived to be disfluent. Cooper (1980) suggests that as many as 5
percent of all children younger than age 5 years experience periods
of disfluency in speaking that are sufficiently severe to be
described as stuttering. Davis (1939) suggests that the decrease
with age of certain types of disfluency indicates that those
disfluencies are normal and therefore can be regarded as transient
or developmental. Persistence with age of syllable repetition and
within-word fragmentation may be the first indication of stuttering
in contrast to developmental disfluency.

Persistent stuttering stands in contrast to developmental
disfluency based on the presence over time of speech, motor, or
emotional involvement associated with the disfluency.

The current study assesses components of disfluency adapted from
Riley and Riley (1979) suggesting that disfluency is pathological or
persistent if it overloads the speech or motor system in one or a
combination of the following ways:

1. respiratory air—flow breaks between syllable or part-word

repetitions,

2. substitution of vowels during syllable or word repetitions,

3. variation in speech rate during syllable or word repetitions,

4. surges of motor tension in articulators, glottis, or

1

respiratory system occurring concurrent with syllable or
part-word repetitions,

5. glottal or phonatory arrests, or

6. abnormal articulatory posturing during consonant production.

In addition, the socioemotional components that define
persistent or pathological disfluency involve frustration in social
situations, avoidance of eye contact, and attempts at avoiding speech
communication.

Normal or developmental disfluency does not involve these
aspects of speech, motor, or socioemotional disruption and is
likely to consist .of repetitions without the overload factors
suggestive of persistent or pathological stuttering.

The hypothesis that stuttering is due to incomplete cerebral
lateralization of language originated in the early part of this
century (Orton, 1927, 1929; Travis, 1931) and has persisted to the
present (Travis, 1978). Early attempts to test this hypothesis were
not successful because of inability to establish a link between
stuttering and handedness (Ballard, 1912; Bloodstein, 1981;
Claiborne, 1917; Daniels, 1940; Rosenfield, 1980). Contemporary
researchers have been successful at establishing differences between
stutterers and nonstutterers in cerebral lateral organization (Jones,
1966; Curry & Gregory, 1969; Brady & Berson, 1975; Sussman &
MacNeilage, 1975; Zimmerman & Knott, 1975; Moore & Lang, 1977; Moore
& Haynes, 1980) and specifically in interhemispheric integration
processes (Fitzgerald, Cooke & Greiner, 1984; Greiner, Fitzgerald &

2

Cooke, 19853, 1985b) and in intrahemispheric competition during
regulation of speech and motor activities (Greiner, Fitzgerald &
Cooke, 19858). The remaining literature review will cover in detail
the research that differentiates stutterers from nonstutterers
during perceptual and production tasks involving speech, and in
addition, will discuss how school-aged stutterers have been

differentiated from nonstutterers.

LITERATURE REVIEW

Stuttering and Hemispheric Contribution t9_Speech Organization

 

Stuttering behavior is best described as a temporal disruption
in the unity of motor patterning of speech (Van Riper, 1971), and
supraglottal articulatory activity has been implicated as a major
factor in this discoordination and disruption in motor sequencing.
Phonation is the central factor in speech production and is a
function of integration and coordination of the complexity of glottal
laryngeal factors, subglottal respiratory processes, and supraglottal
articulation. The specific phonetic and linguistic aspects of a
particular language -are especially important because phonetic
segment duration is determined physiologically by the rates of
movement of the supraglottal articulators. Furthermore, Wingate
(1977) has suggested that stuttering consists of defective transition
from one phoneme to another. The consonant—vowel—consonant
combinations most often are the source of the stuttering blocks, and
it is these consonant-vowel-consonant combinations that require rapid
sequencing and differentiation phonetically. Hypothetically, the
phonetic transition defect is most pronounced during speech pressure
and communicative stress that are typically associated with
increased neuromotor speech movement (Zimmerman, 1980).

Speech production is a variable dimension described by rate,
rhythm, and intonation of speech as well as vocal intensity. Slowing
the rate of speech, regularizing the rhythm of speech, speaking in a

monotonic voice, whispering, or speaking with much increased vocal
4

intensity all have been shown to reduce stuttering blocks in
frequency and severity. The vocalization modification hypothesis
suggests that modified vocalizing in and of itself induces fluency.
Zimmerman (1980) suggests, however, that the overriding change is in
reduction of movement variability as it occurs, for example, in the
simplified neuromotor demands of whispering or in the imposed rhythm
of singing.

Neuropsychological models of speech behavior into which
stuttering might fit include models of cerebral dominance or
hemispheric specialization for temporal aspects of speech and
nonspeech manual performance. Studies with normal speaking adults
have demonstrated that speech concurrent with manual activity
interferes with manual performance. Specifically, normal
speakers have poorer dominant hand performance compared to their
nondominant performance (Hicks, 1975; Hicks, Bradshaw, Kinsbourne &
Feigin, 1978; Lomas & Kimura, 1976; Kinsbourne & Cook, 1971; Wolff &
Cohen, 1980; Hellige & Longstreth, 1981; Thornton & Peters, 1982).
However, the degree of interference varies as a function of such
factors as speech task complexity (Hicks, 1975; Hicks et. al., 1978;
Thornton & Peters, 1982) demand characteristics of the task (Lomas,
1980; Nachshon & Carmon, 1975; Thornton & Peters, 1982), and subject
handedness (Lomas & Kimura, 1976). One neuropsychological model
assumes that there is interference between concurrent activities
controlled by the same hemisphere. When two cerebral control centers
are concurrently active, as during the performance of unimanual

5

sequential finger tapping and unsequenced, propositional speech, they
interfere with each other inversely with their anatomical distance
from each other, and directly with the amount of activity required of
each center for the particular motor task.

In addition, Lomas and Kimura (1976) suggest that the
interference between speaking and manual activity is related to the
"limited cerebral space" concept in that both speech and right hand
movement are controlled by the same hemisphere. More specifically,
these authors suggest that the overlap in the left hemisphere is for
speech and rapid movement sequences of the contralateral hand. They
raise the further possibility that rapid positioning of a limb or
parts of a limb, with minimal visual guidance, is the factor related
to lateralized decrement in concurrent speaking tasks. If this is
true, the contribution of the left hemisphere to speaking may also be
in the control of rapid placement of the articulatory musculature.

The articulatory sequencing aspects of speech and unimanual
sequential finger tapping are both peripheral-level aspects of
speech production. An overall model of neuropsychology relevant to
stuttering behavior and the stuttering block, is the Aldridge
(1981) hypothesis of central-level and peripheral-level processing in
speech production. This model suggests that the central level of
speech production requires activation of organization mechanisms also
required for rehearsal of information in short-term memory, as would
occur in spontaneous, propositional speech. The peripheral level of
speech production involves a peripheral execution-controlling level

6

that places little demand on the central phonetic-organizational

process.

The central-level processes involve mechanisms for active
programming of articulatory gestures with the peripheral-level
mechanisms executing these preprogrammed phonetic sequences.
Aldridge (1981) suggests that if motor movements (speech or unimanual
sequencing) can be accurately made in the absence of feedback, the
inference can be made that the movement is programmed in advance,
with the execution being ballistic and independent of feedback.

In a recent study (Greiner et. al., 19853), concurrent speech
(spontaneous speech, reading aloud, and singing) and unimanual
sequential finger tapping resulted in interference with motor
activity. The interference in this study occurred especially during
spontaneous speech tasks and was measurable by disruption in ability
to sequence the speech and disruption in the ability to sequence
unimanually. The speech production tasks most likely programmed in
advance (preprogrammed) were singing and reading aloud, and in fact,
these speech tasks produced less interference on unimanual finger
sequencing than spontaneous speech and, in addition, were interferred
with less by finger sequencing. With respect to manual interference
as a function of speech fluency, the only significant effect
occurred in the spontaneous speech task in which stutterers had
slower tapping rates than nonstutterers, regardless of the hand used
for tapping. One strategy for optimizing performance in the
concurrent task would be to slow the rate of manual activity, speech,

7

or both, in an effort to gain maximum control of one of the component
processes or to allow sufficient time for integration of speech and
motor movements (Helm-Estabrooks, 1983). Since tapping rates did not
slow down during spontaneous speech, whereas speech rates did, all
subjects apparently allocated less attention to speech than they did
to tapping during the spontaneous speech condition. Conversely,
tapping rates for reading and singing tasks were higher than those
for spontaneous speech. Singing, and to a lesser extent, reading
provide inherent rhythmic cues that could serve to synchronize motor
speech functions. For example, the song used in the Greiner et 31.
(19853) study, "Row, row, row your boat," has a compound duple meter
(6/8 time). Since the right hemisphere appears to be specialized for
processing melody (Borod & Goodglass, 1980), the discourse function
of language (Moscovitch, 1983), and certain suprasegmental features
of speech (Marcie, Hacaen, Dubois, & Angelerques, 1965), it is
possible that the rhythmic qualities of music or prose provide
exogeneous temporal regulation to the right hemisphere, which,
through interhemispheric processes, allows the left hemisphere to
perform synchronous speech and motor activity more efficiently.
Spontaneous speech typically does not have the same melodic or
rhythmic qualities of reading or singing. Moreover, during the
Greiner et al.(l9853) study, subjects had to simultaneously tap and
think about what they were going to say relative to the
context in which speech was required. The fact that
interference occurred only in the spontaneous speech condition, can

8

probably be attributed to the lack of inherent structure or rhythm in
spontaneous speech as compared to singing or reading. Inasmuch as
spontaneous speech parallels everyday conversation, one might suppose
that the spontaneous speech condition also heightened task-dependent
tension in some of the stutterers. In addition, if the right
hemisphere is specialized for negative emotions, as Campbell
(1982) has argued, then there is additional evidence to support the
hypothesis that interhemispheric processing deficits can be linked to
the tapping rate deficits in stutterers.

The results of the Greiner et. 31. (19853) study also indicate
that concurrent motor tasks interfere with speech production.
Concurrent spontaneous speech slowed speech rates for stutterers and
nonstutterers as compared to their pretest speech rates. Although
there were no differences between groups during any pretest speech
task or during concurrent singing or reading, stutterers' speech rate
was slower than nonstutterers during concurrent spontaneous speech.
With respect to speech disfluency, concurrent spontaneous speech
increased disfluency in stutterers and nonstutterers. Stutterers
were more disfluent than nonstutterers during pretest and concurrent
spontaneous speech, but no differences occurred during concurrent
reading or singing.

Some researchers attribute interference effects to an imbalance
between the activation and inhibition of speech and motor control
systems of the left hemisphere (Denenberg, 1980; Lomas, 1980; Young,
Bowman, Methot, Finlayson, Quintal & Boissonneault, 1983). However,

9

in the Greiner et 31. (19853) study, interference occurred in the
left hand of right-handed subjects, suggesting that right
hemispheric activity also is involved. Such interhemispheric
processing has been related to the left hemisphere's ability (or
inability) to inhibit the function of right hemisphere motor activity
(Wolff & Cohen, 1980).

Peters (1980) suggests that temporal regulation is the key
executive function of a laterally specialized hemisphere. Inasmuch
as the speech musculature and the sequencing of movements involved in
speech require fine-tuned temporal regulation, disturbances in the
motor lead control of the left hemisphere should lead to disruption
of the sequential manual performance during concurrent speech and
manual tasks. For right-handed subjects, disruption seem to involve
primarily intrahemispheric competition. The activation—inhibition
imbalance would seem to disrupt the timing of neural control
processes regulating the integration of speech and motor activity
(Kelso, Tuller, & Harris, 1983).

The results from the Greiner et al. (19853) study suggest,
then, that regulation of speech and motor control systems is
more influenced by interhemispheric integration processes than by
intrahemispheric competition. Moreover, to paraphrase Moscovitch
(1983), when system overloads occur, one hemisphere's role in normal
interhemispheric control processes may become impaired. For
stutterers, these problems seem to be related to difficulties in the

temporal regulation of the right hemisphere, which interferes with

10

the balance between the right and left hemisphere activation and
inhibition.
Development g£_Hemispheric Contribution to Speech Organization

The temporal organization of speech in most righthanders arises
from the left hemisphere, which is specialized for temporal
sequencing of motor tasks. The development of temporal organization
in speech and nonspeech motor tasks is of interest relevant to three
separate hypotheses differing on the age at which lateralized
function emerges, either at puberty, at age 5 or at age 3. The
earliest hypothesis suggests progressive development of cerebral
dominance with the implication that the infant and young child have
bilateral language . skill and gradually develop increasing
lateralization (Lenneberg, 1967). This progressive lateralization
hypothesis suggests that by puberty, the left hemisphere has
increased specialization and the right hemisphere has a decreased
role (Gaddes, 1980). A later view of the progressive lateralization
hypothesis suggests that full maturation and lateralized function
occurs by age 5 (Krashen, 1973).

The progressive lateralization hypothesis has been weakened,
however, by research demonstrating lateralized function in infants
and preschoolers (Kinsbourne, 1975b; Hiscock & Kinsbourne 1978;
White & Kinsbourne, 1980). White & Kinsbourne (1980) had
children ages 3 to 12 tap on a Morse key with their index finger
while they either recited a nursery rhyme, recited animal names, or
memorized shapes. White and Kinsbourne (1980) suggest that testing
lateralized function in young children is possible by predicting

11

interference of motor tasks controlled by the same hemisphere when
concurrent performance is required. Right hand tapping and talking
both are controlled by the left hemisphere whereas left hand tapping
and talking are controlled by different hemispheres. Relevant to
silent tapping, concurrent tapping and talking caused a greater drop
in right hand tapping than in left hand tapping in rhyme and animal
recitation conditions. Shape memorization interfered with tapping
equally for both hands. Moreover this left hemisphere
lateralization of speech output control did not vary with increasing
age supporting the view that speech output control is fully
lateralized at least by age 3 years.

The issue in speech development and in the development of
attentional organization is central language development and
peripheral—level speech production. Assuming there are no central
language processing or production difficulties, difficulties in
speech production such as stuttering might be addressed by the
attention allocation hypothesis. This hypothesis suggests that what
is required in learning to speak fluently is the ability to
automatize motor performance in addition to organizing thoughts.
Rather than two separate processes occurring at different points in
time, concurrent formulation of thought and peripheral execution of
speech in varying social contexts is what is expected of the speaker.

Assuming it is this concurrent formulation and production that
produces disfluency, it is necessary to examine more closely speech
development and the development of mechanisms responsible for

12

temporal sequencing and integration of temporal organization of
competing speech and nonspeech motor tasks.
Developmental Mechanisms 2f_§peech and Nonspeech Motor Coordination
The development of speech and nonspeech manual fine motor
coordination can be discussed as arising from: 1) the development of
left hemisphere specialization for temporal sequencing; or 2) an
increase in the efficiency of interhemispheric transfer of
information and hemispheric integration.

The development .2: left hemisphere specialization. The

 

 

strongest evidence currently suggests that as early as age 3,
right-handed children have left hemisphere specialization for speech
since these children have lower right hand compared to left hand
tapping while concurrently talking. (Ramsay, 1979; Hiscock &
Kinsbourne, 1978; Kinsbourne & McMurray, 1975).

Ramsay (1980) found evidence that a relationship exists between
the onset of bimanual handedness and acquisition of dissimilar
syllables in babbling, with data suggesting that the structural
changes in infants' vocalizations indicate the use of different
articulatory units and reflects successive levels of hemispheric
specialization during the first year of life. Ramsay
(1980) speculates that what matures are the motor programs that
sequence the separate movements of the vocal apparatus and that these
programs are controlled by the left hemisphere.

Wolff and Hurwitz (1976) studied the development of finger

tapping in boys and girls and found that from ages 5 to 16 years,

13

girls were consistently more accurate than boys in entraining their
tapping rate to an external beat and in tapping to 3 steady rhythm.
The right hand of all children in this study was steadier than the
left, but the manual asymmetry for regularity of tapping was greater
in girls than boys. Wolff and Hurwitz (1976) suggest that the left
hemisphere is specialized for cortical functions controlling the
serial organization of simple motor repetitions, and these functions
mature earlier in girls than in boys. The authors point out that
girls are developmentally advanced relative to boys in other selected
functions such as onset of speech, expressive language, speech
articulation, and verbal fluency, and that inasmuch as all of these
cortical functions are associated with left hemisphere
specialization, implying later left hemisphere specialization
for speech in boys.

Given that the ratio of stuttering in boys and girls is
considered to be 4 or 5 to 1 '(Bloodstein 1981), one possible
developmental mechanism for stuttering, then, might be a delay in
left hemisphere specialization resulting in difficulty with temporal
sequencing tasks. However, this view does not account for right
hemisphere involvement in speech and speech-related tasks,
necessitating discussion of left and right hemisphere integration.

The development g£_interhemispheric transfer and inhibition.

 

Communication between the two cerebral hemispheres is attributed to
fibers of the corpus callosum and the myelination of these fibers is

seen as the mechanism for emergence of developmentally successive

l4

phases of the organization of behavior patterns (Yakolev, 1962;
Yakolev & Lecours, 1967; Lecours, 1975).

The functional importance of the corpus callosum in development
is not yet well established (Selnes, 1974), and much of the evidence
of corpus callosum function comes from studies of partial and
complete commissurotomy patients (O'Leary, 1980). Denkla (1974)
reported findings that in right—preferring children, right sided
function is established first, then a rapid increase occurs in left
sided function, so that by the age of 8 years, there is a very small
mean right superiority within individuals. Denkla (1974) suggests
that the interhemispheric connections develop around age 8 resulting
in complete left hemisphere control of fine motor output. Yakolev
and Lecours (1967) note that while myelination of the callosum is
largely complete by age 6, it continues at a slow rate until at least
age 10. Denkla (1974) suggests that maturation of the
interhemispheric connections is an appealing hypothesis based on
reports that in contrast to the closely similar right and left
tapping rates of normal adult subjects, patients with commissurotomy
had a left inter-tap interval 40 to 70 milliseconds longer than their
right (Kreuter et 31., 1972), inferring delayed interhemispheric
communication.

Ellenberg and Sperry (1980) studied commissurotomy patients and
their ability to voluntarily maintain independent left and right side
performance during double simultaneous hand performance. Their

results suggest that the cerebral commissures force the two

15

hemispheres to work together and maintain attentional unity in the
intact brain. Practice increases the capacity for simultaneous
processing in normals, but this enhancement is most readily
interpreted as the result of automation of performance which
decreases the need for attentional supervision of each of the
independent left and right side functions during simultaneous
handwriting.

Supporting this view, Dennis (1976) and Chiarelo (1980) suggest,
on the basis of studies of congenital acallosal persons, that the
corpus callosum provides the inhibition necessary for the development
of accurate topographic somatosensation and also for precise motor
control. the role of interhemispheric communication in the control
of precise motor coordination has also been extensively studied.
Preilowski (1975) demonstrated that commissurotomy patients were able
to perform bimanual coordination tasks postoperatively if those tasks
had been well learned prior to the surgical division. In contrast,
the patients were unable to maintain synchronous bilateral movements
with apparent lack of attentional unity and usually performed at
different rates with the right and left hands. Preilowski (1975)
indicates that complete commissurotomy patients find the bimanual
coordination tasks easier and perform it more accurately when the
task requires mirror-image production as opposed to asymmetric
movements. Preilowski (1975) suggests that limb movements are
negatively influenced by simultaneous action of the contralateral

extremity and that the interference occurs at the cortical level via

16

callosal interhemispheric connections.

Cohen (1970) suggests that interference occurs when limited-
capacity of a central processor for movement-generated feedback is
exceeded. Simultaneous, bimanual mirror-image movements involve
homologous muscles and ostensibly redundant feedback, whereas
simultaneous parallel movements involve nonhomologous muscles and
generate a greater amount of feedback. The corpus callosum functions
as the inhibitor of feedback and this function would seem to be
completely developed around the age of 8 to 10 years.

Bimanual simultaneous handwriting has traditionally been used
as an indicator of,laterality (Harris, 1957) and as a tool to
differentiate school—aged stutterers and nonstutterers (Spandino,
1941; Travis, 1930). Travis (1930) found that normal-speaking adults
usually write with the same orientation with both hands when writing
simultaneously with the right and left hands with vision occluded.
By contrast, stutterers very frequently show the opposite
orientation in the script written with one hand as compared to the
other, and this, Travis suggested was indicative of immaturity since
it is more prevelant in children than adults.

Bryngelson (1935), in a study of 700 stutterers ages 4 to 18,
found that 802 wrote mirror script during bimanual handwriting
compared to 152 of a normal population of adults. Ninety—two percent
of the stuttering children between ages 9 and 16 had mirror reversals
in bimanual handwriting. In the children older than age 17, mirror

writing occurred in 60 to 70% of stutterers.

17

 

In

Spandino (1941) studied 70 stuttering and nonstuttering children
ages 8 to 12 on a test of bimanual simultaneous drawing of
letter-like designs. There were no significant differences between
the stutterers and nonstutterers. Corballis and Beale (1976) suggest
that it is easier to write backwards with the nondominant hand while
writing forward with the dominant or preferred hand. Further, Clark
(1957) tested 11 and 12 year old normal children on a test
requiring them to write digits rapidly with both hands
simultaneously. Over 50% wrote normally with the preferred
hand and reversed with the nondominant hand.

What seems conclusively important during development of motor
skills is the increasing ability to allocate attention and counteract
interferring feedback. Counteraction of feedback occurs through the
callosal interhemispheric inhibition effects so that what occurs by
the age of 10 to 12 is seen as the development of neural circuitry to
make possible the attentional control of lateralized performance.

Development of Hemispheric Control 2f_the Gradient 2£_Attention

 

According to Kinsbourne (1970), a motor response is facilitated
in relation to the direction of orientation of attention. Any simple
response controlled by the left hemisphere will benefit from
environmental stimulation that elicits an orientation to the right
side of space. When the focus of attention must be straight ahead,
the hemispheres are mutually inhibited. The orientation model is an
expectancy model, which suggests that when subjects know where the

stimulus will be presented and what type of stimulus to expect,

18

interhemispheric transmission times are reduced to an almost
negligible nerve conduction time across the callosum. ‘Thus,
hemispheric specialization may be exaggerated or obscured merely by
shifting attention between hemispheres, so if the right hemisphere is
cued, the advantage of the left hemisphere in any given task is
diminished or eliminated. During bimanual handwriting of language
symbols, one expects priming of the left hemisphere. Kinsbourne
suggests that this priming of the left hemisphere results in an
orientation movement to the right hand and renders the right
hemisphere more ready for its characteristic performance, which would
produce mirror script in the left hand. The corpus callosum
functions in communication of attentional bias and therefore inhibits
production of this mirror script. Both the young child and the
callosally sectioned adult lack this inhibition, which amplifies the
effect on attention of concurrent lateralized cognitive activity.
When interhemispheric communication occurs, a person can write
normally with the contralateral extremity because of the minimal need
for allocation of attention.

Interference on automatic processes can occur at several
different levels in motor tasks. For example, in speech production,
the hemispheric orientation or attentional bias model predicts that
speaking will create an attentional bias to the right hand in
righthanded persons. In stutterers, one might speculate that the
automaticity of the peripheral level speech process is not possible

because of interfering speech organization from the right

19

hemisphere (Moore & Lang, 1977; Moore & Haynes, 1980) and that a
major difficulty for stutterers is temporal regulation of the right
hemisphere. It is important to reiterate that vocalization that is
right hemisphere specialized, such as singing and whispering,
diminishes stuttering (Bloodstein, 1981). In addition, temporal
regulation is the key executive function of a laterally specialized
hemisphere so that if the right hemisphere is not efficiently
regulating temporal sequencing in stutterers, singing or speaking in
metronomic rhythm will eliminate stuttering. Shames and Florence
(1980) also suggest that conscious monitoring of the speech signal
will assist in regularizing its rate and rhythm. The difficulty for
the stutterer arises when the attention required for supervision of
the speech signal is required for central formulation of speech as in
spontaneous speech under social pressure.

There is evidence from research with adult stutterers
(Fitzgerald, Cooke & Greiner, 1984; Greiner, Fitzgerald & Cooke,
1985b) that, compared to adult nonstutterers during bimanual
handwriting, stutterers show significantly poorer handwriting
organization of the left hand and more mirror image reversals with
the left hand. Fitzgerald et al. (1984) concluded that what might
appear to be incomplete cerebral dominance may be inefficient
interhemispheric coordination or disfunctional interhemispheric
integration of information. For stutterers, the underlying
difficulty may be inability of the left hemisphere to achieve control

over the right hemisphere due to a general deficiency in

20

\interhemispheric integration of motor, spatial, and/or temporal
components of speaking.

If the left hemisphere is actually specialized for the temporal
regulation of speech by the age of 3 years, then what is it that
the left hemisphere has to regulate during development of speech and
nonspeech motor skills?

In light of recent studies of developmental disfluency occurring
immediately prior to age 3 (Yairi, 1982), it is possible that this
transient stuttering in children is occurring simultaneous with the
developing organization of lateralized motor skills. Tingley and
Allen (1975) studied the development of speech timing control in 5 to
11 year-old children and found that both the timing control of speech
and finger tapping increased with age. Similar variability in
speech control and tapping occurred suggesting a common
timing-control mechanism. Tingley and Allen (1975) reported also
that individual differences existed in children's timing control and
suggested that clinical test procedures be developed to identify
future stutterers or to give a better understanding of the lack of
improvement in cases of functional or normal disfluency.

Existing literature on normal, developmental and pathological
disfluency and the development of speech organization will now be
discussed.

Speech Organization and Developmental Disfluency
There is considerable agreement that young children as compared

to older children are more likely to have speech organization that is

21

perceived to be disfluent. Cooper (1980) suggests that as many as 5
percent of all children younger than age 5 years experience periods
of disfluency in speaking of sufficient severity to be described as
stuttering. Davis (1939) studied the speech fluency of 62 boys and
girls ranging in age from 2 to 5 years and found that phrase
repetitions were the most common kind of disfluency, followed by
whole-word repetitions. These phrase and whole-word repetitions
comprised 25 percent of the disfluencies and were considered "normal
disfluency". Less common disfluencies were syllable and part—word
repetitions. Whole-word and phrase repetitions decreased in the
older children whereas the part—word and syllable repetitions
remained at the same level.

Davis' (1939) study suggests that the decrease with age of
certain types of disfluency means that those disfluencies are normal
and can be considered transient or developmental disfluency. Yairi
(1981, 1982) suggests that transient disfluency peaks between the
ages of 2 and 3. Beyond age 3, the disfluency that persists is likely
to consist of syllable and part-word repetitions. Within-word
repetitions in speech indicate more fragmentation of speech
organization than phrase or whole-word repetitions.

Differentiation pf Developmental and Pathological Disfluenpy

The developmental disfluency question can be addressed from two
viewpoints. The first is the view that disfluent speech in a child
younger that age 5 can be used to differentiate a stutterer from a

nonstutterer. The second view is that no differences exist between

22

stuttering and nonstuttering children (Johnson, 1955) and that
stuttering emerges out of the recognition and labelling of normal
disfluencies as "stutters". Johnson (1942) concluded that in 92
percent of the children diagnosed as stutterers, stuttering
involved effortless repetitions of words, phrases, and syllables.
This second viewpoint is the diagnosogenic theory of stuttering,
which has not been totally supported by stuttering research.
Johnson, Young, Sahs and Bedell (1959) revised the theory to more
comprehensively address the importance of listener reaction to the
stuttered speech and the impact of this. reaction and social
interaction on the stutterer.

Today most researchers do agree, then, that early disfluency can
be differentiated as stuttering as opposed to developmental
disfluency based on the presence of syllable or part—word
repetitions. Bjerkan (1975) concluded that the fragmentation of a
word before the whole word is pronounced is the most characteristic
feature that distinguishes the speech of stuttering from
nonstuttering children. These fragmentations have been more clearly
defined (Bjerkan, 1980; Wingate, 1964) to include part-word
repetitions, silent or audible prolongations within words, or
interjections within words.

Bjerkan (1980) studied 110 nursery school children between the
ages of 2 and 6 years and concluded that the nonstuttering children
had whole—word repetitions, which decreased with increasing age, and
also, had no within—word fragmentations.

23

The persistence with age then, of syllable repetition and
within-word fragmentation may be the first indication of pathological
disfluency or stuttering in contrast to developmental disfluency.
Stuttering can be differentiated from normal developmental disfluency
by the presence of disrupted speech sequencing within words, in
addition to the persistence of total disfluency with increasing age.
This basis for differentiation, however, only includes speech
assessment. Persistent stuttering stands in contrast to
developmental or normal disfluency based on the presence over time of
speech, motor, or emotional system components associated with the
disfluency.

Components pf Disfluency

 

The differentiation of developmental and pathological disfluency
needs to include aspects of speech and nonspeech system coordination.
Phonation is the central factor in speech production and is a
function of integration and coordination of the complexity of glottal
laryngeal factors, subglottal respiratory processes, and supraglottal
articulation. Research describing persistent stuttering in adult
stutterers suggests that in comparison with childhood stutterers,
adults are more likely to exhibit articulatory, phonatory or
laryngeal, and respiratory correlates of stuttering. The persistence
over time of speech, motor, or emotional system involvement
associated with the disfluency differentiates pathological

stuttering from normal developmental disfluency.

Disfluency is pathological or persistent if it overloads the

24

speech or motor system in one or a combination of the following ways:

1. respiratory air-flow breaks between syllable or part—word

repetitions,

2. substitution of vowels during syllable or word repetitions,

3. variation in speech rate during syllable or word repetitions,

4. surges of motor tension in articulators, glottis, or

respiratory system occurring concurrent with syllable or
part—word repetitions,

5. glottal articulatory posturing during consonant production,

6. abnormal articulatory porturing during consonant production.

In addition, the socioemotional components that define
persistent or pathological disfluency involve frustration in social
situations, avoidance of eye contact, and attempts at avoiding speech
communication.

Normal and developmental disfluency do not involve these aspects
of speech, motor, or socioemotional system disruption and are likely
to consist of repetitions without the overload factors suggestive of
persistent or pathological stuttering.

In further description of the components of pathological
disfluency, evidence exists for a progressive increase in component
involvement with age in that children younger than age 8 or 9 years
may not have the complexity of speech, motor, or emotional system
involvement that appears in older children and adults who stutter
(Cullinan & Springer, 1980); Schmitt & Cooper, 1978). Cullinan and
Springer (1980) report that stutterers under the age of 8 years do

25

not differ from nonstutterers on phonation measures of voice
initiation time and voice termination time, whereas stutterers above
8 years of age demonstrate slower initiation and termination of
phonation than do nonstutterers. These researchers suggest that
phonatory differences develop after the child has been persistently
stuttering and possibly as a result of stuttering experience.

Schmitt and Cooper (1978) compared stuttering and nonstuttering
children (ages 7 to 12 years) with respect to fundamental frequency
as a central measure of phonatory behavior. These researchers found
that on an oral reading test, there were no significant differences
between stuttering and nonstuttering children on mean fundamental
frequency, the lowest fundamental frequency, the highest fundamental
frequency, or the difference between the lowest and highest
fundamental frequency of the voice. Many researchers have found
phonatory differences between adult stutterers and nonstutterers on
measures of phonatory processes (Schwartz, 1974; Adams & Reis, 1971;
Adams & Hayden, 1974; Conture et al., 1974; Freeman & Ushijima,
1974; Agnello, 1975; Freeman, 1975; Kerr & Cooper, 1976).

Schmitt and Cooper (1978) suggest that lack of differences in
phonatory behavior between childhood stutterers and nonstutterers
supports the view that the differences between adult stutterers and
nonstutterers may be the result of "habituated compensatory phonatory
adjustments" in response to disfluency. This view suggests that
disfluency in childhood is a relatively automatic speech process and

that in attempting to avoid or prevent stuttering, the older child

26

 

Ir—v

and adult stutterer attend to the peripheral speech system and

de—automize the process.

One would expect, then, that this de-automization of the
peripheral speech process in stuttering children is one of the
factors producing speech and motor aspects of pathological
disfluency. Therefore, study of the developmental progression of
these speech and motor components will describe the peripheral-level
production deficits of persistent or pathological disfluency.

The literature suggests, then, that childhood stutterers may
exhibit one or any combination of factors which define their
individual stuttering behavior (Riley & Riley, 1979; Riley & Riley,
1980; Cullinan & Springer, 1980). Overall there is considerable
agreement that childhood stutterers are a heterogeneous population.
The nature of the differences among them can probably be described on
the basis of differing types and degrees of speech and nonspeech
motor involvement as well as social and emotional stress. To assist
in definition of the heterogeneity within stutterers, a diagnostic
system is suggested.

Diagpostic Components 9f Speech Disorganization i£_Children

Cullinan and Springer (1980) suggest that stuttering—only
children need to be differentiated from stuttering—plus children, or
children who have other language disorders in addition to stuttering.
Riley and Riley (1980) suggest that a diagnostic system be used with
children and that this analysis include observation and testing of

the following neurological or neurogenic areas: 1) disorders of

27

attention; 2) disorders in coordination and planning of speech and
nonspeech motor systems; 3) disorders in central speech and language
formulation; and 4) disorders in processing auditory information.

In addition to neurological or neurogenic components in the
developmental progression of stuttering, Riley and Riley (1979)
suggest that emotional stress and emotional overload is apparent in
cases of persistent or pathological disfluency in children. Research
with adult stutterers suggests that interpersonal and emotional
stress is important in the description of stuttering in finding
avoidance behavior (Bloodstein, 1981; Prins & Lohr, 1972) and
significantly higher levels of general anxiety as measured by the
Revised Willoughby Personality Schedule (Greiner, Fitzgerald, Cooke
& Djurdjic, 1985). The Greiner et al. (1985) study also
suggests that stutterers have higher social sensitivity and social
isolation and lower levels of social confidence as measured by the
WPS-R. Greiner et al. (1985) suggest that these WPS-R
differences between adult stutterers and nonstutterers be
conceptualized as points on a continuum, much as Adams and Runyan
(1981) have proposed about fluency-disfluency itself. Some
stutterers do not exhibit high social sensitivity, social isolation,
or low social confidence. Janssen and Kraaimaat (1980) suggest that
the influence of general anxiety may be restricted to stutterers
whose speech is excessively fast and repetitive and to those whose
speech is dominated by excessively slow repetitions. There will be

individual stutterers whose stuttering is affected by word-specific

28

anxiety, speech-situation anxiety, or general anxiety. In
addition, there will be some stutterers for whom anxiety is not a
contributing factor in their disfluency.

It is apparent, then, that speech rate and emotional stress can
be coexisting components which define and thereby affect therapy
for individual stutterers. Assessment of stuttering needs to
include speech, nonspeech motor, and emotional stress instruments to
completely diagnose stuttering components. This is particularly
critical given the possibility that stuttering involves inefficient
right hemisphere regulation of speech in addition to
regulation of negative emotions (Campbell, 1982). The
emotional component and the speech regulation component are
controlled by the same hemisphere, so that when emotional stress
occurs simultaneous with the demand for speech regulation,
temporal regulation is disrupted.

Children who stutter may have other speech and language
disorders that need to be differentiated in the therapy plan.
Stuttering—only children or "functional" stutterers in whom
stuttering is the only speech difficulty have been found to differ
on neuropsychological tests, which suggests that there is a lack of
homogeneity even in this subgroup of stutterers (Daly & Smith,
1976; 1979; Daly, Kimbarrow & Smith, 1977). Daly and Smith (1979)
suggest that functional stutterers with three or more
neuropsychological deficits might have organic cerebral or

neurological dysfunction.

29

To establish a theoretical framework for discussion of
neuropsychological deficits and organic cerebral or neurological
dysfunction (Daly & Smith, 1979), and neurological or neurogenic
components (Riley & Riley, 1979) in childhood stutterers, it is first
necessary to discuss the relationship between the development of
speech organization and the development of attention.

Speech Organization and Attentional Development

The normal developmental progression of learning to speak
involves transient disfluency between the ages of 2 and 3 (Yairi,
1982). To understand the commonality between disfluency as a
developmental process and disfluency as a persistent disruption in
adults, the Aldridge (1981) hypOthesis of two levels of processing in
speech production seems useful. The Aldridge hypothesis suggests
that speech production involves a central-level process requiring
speech organization and active conscious processing, and a
peripheral—level process controlling execution of speech
automatically and placing little demand on the central organizational
process. The degree of automaticity indexes the degree of learning
of particular tasks, and Sperry (1961) suggests that highly
overlearned motor functions may descend to lower brain functions.
The conscious working memory required in generative organization of
thought would involve the cortical central-level process. Speech
motor tasks at any point in time are organized and therefore are
dependent on the degree of maturation of brain structure, degree of

language learning, and, in addition, the type of speech task being

30

performed.

Speaking is generally an automatic process, with the exception
of spontaneous propositional speech, which is full of disfluency,
hesitations and pauses in normal speakers (Goldman—Eisler, 1968).
Spontaneous propositional speech is also associated with increased
stuttering in stutterers, whereas singing is likely to decrease
stuttering in stutterers (Greiner et 31., 19853). Therefore, when
the speech task is automatic, fluency is expected in stutterers and
nonstutterers. However, stutterers learn during speech development
to fear certain words or speaking situations (Bloodstein, 1981)
resulting in acute awareness of the peripheral-level process of
phonetic production. This conscious processing of the
peripheral-level process decreases the automaticity of its execution.
Rieber et al. (1976) suggest that when attention and/ or expectation
is shifted from its appropriate central-level operation of cognitive
planning to the peripheral-level operation of phonetic production,
this tends to de—automize the communicative behavior.

This view suggests that disfluency can be a relatively automatic
speech process and that in attempting to avoid or prevent stuttering,
the childhood or adult stutterer attend to the peripheral speech
system and de-automize the process. Adult stutterers are usually
very aware of phonetic combinations or speaking situations that
exacerbate their stuttering. The anticipatory struggle hypothesis
of stuttering reflects this expectation. This hypothesis suggests a

degree of conscious awareness of the speech apparatus prior to and

31

associated with stuttering blocks.

If, indeed, the conscious processes associated with speaking
underlie stuttering and developmental disfluency, it is
conceivable that conscious strategies such as monitoring are
influential in resolving stuttering and developmental disfluency by

diminishing attentional demands on right hemsiphere processing.

32

General Procedure and Hypotheses
The present study was designed to assess components of speech

disfluency in male stutterers and nonstutterers between the ages of 6
and 16. Hypotheses reviewed suggest that developmental and
pathological disfluency have common mechanisms but differ in the
degree of associated speech and nonspeech motor disorganization and
on the presence of social and emotional stress.

Based on the preceding literature review, the following

predictions were made:

1) During bimanual handwriting tasks, stutterers will have
poorer handwriting organization and greater frequency of
mirror image writing with their nondominant hand than
nonstutterers;

2) During concurrent spontaneous speech and unimanual
sequential finger tapping, stutterers will be more
disfluent and have more finger sequencing errors than
nonstutterers;

3) Demand for spontaneous speech will cause a greater increase
in disfluency in stutterers than in nonstutterers;

4) Demand for spontaneous speech will cause a greater increase
in within-word fragmentation in stutterers than in
nonstutterers;

5) Older stutterers will have higher emotional stress
and social sensitivity and lower sociability, social

confidence and self esteem than will nonstutterers and

younger stutterers.

33

METHOD

Subjects

The subjects were 60 right—handed boys, including 30 stutterers
(age 6 to 8.11, n=7; age 9 to 11.11, n=12; age 12-15, n=11), and 30
nonstutterers (age 6 to 8.11, n=9; age 9-11.11, n=9; age 12—15,
n=12). The stutterers were recruited from the Michigan State
University Speech and Hearing Clinic, The University of Michigan
Speech and Hearing Sciences Clinic, and the Lansing School District.
The nonstutterers were recruited from the Lansing School District.

Informed consent was obtained from the children's parents prior

to their participation in the study (see Appendix A).

Procedure

Screening evaluation .9: language processipg. Language
processing was assessed using the elementary and advanced (as age
appropriate) screening tests of the CELF (Clinical Evaluation of
Language Functions; Semel & Wiig, 1980). Initially the subject
observed the experimenter during demonstration items and then
received three practice trial items. Test trials involved the
subject listening to directions and responding correctly to stimulus
statements (e.g., Simon says: Touch your head above your ears.).

The language processing screening items were scored by marking
an appropriate score of l for correct and O for incorrect and the
total raw score was converted to an age appropriate percentile rank.

Screenipg evaluation .2; language pgoduction. Language

production was assessed using the elementary and advanced (as age

34

appropriate) screening tests of the CELF (Clinical Evaluation of
Language Functions; Semel & Wiig, 1980). Initially the subject
observed the experimenter during demonstration items and then
received three practice trial items. The test trials involved the
subject listening to directions and responding correctly to the
stimulus statement (e.g., "Repeat this word after me:
°Tach3pheminopia'").

The language production screening items were scored by marking
an appropriate score of l for correct and 0 for incorrect and the
total raw score was converted to an age appropriate percentile rank.

Subjects were not included in the current study if they did not
achieve age-appropriate percentile ranks on the language processing
or production screening tests.

Evaluation pf hand preference. Hand preference was assessed
with the Harris Tests of Lateral Dominance (Harris, 1957). On this
test, the subject is expected to simulate ten hand preference items.
The items to be simulated are throw a ball, wind 3 watch, hammer a
nail, brush your teeth, comb your hair, turn a door knob, hold an
eraser, use scissors, cut with a knife and write. Since this study
involved right-handed subjects only, all subjects had to perform 80%
of 10 hand preference items with the right hand to be included.

Bimanual handwriting. Bimanual handwriting performance was
assessed using a simultaneous handwriting task requiring bimanual
coordination modified from previous research (Fitzgerald et 31.,
1984; .Greiner et 31., 1985b). The stimuli for the bimanual task

35

were the digits from 1 to 12 and the letters from A through L (see
Appendix B). Bimanual handwriting was assessed for digits and
letters across five separate tasks: Task 1 (bimanual handwriting
task with no speech or lateralized attending); Task 2 (task 1
replication); Task 3 (concurrent bimanual writing and saying aloud
each digit or letter as it was being written); Task 4 (concurrent
bimanual writing and lateralized attention allocation to the left
hand) and ; Task 5 (concurrent bimanual writing and lateralized
attention allocation to the right hand). Tasks 4 and 5 were
distributed across all subjects so that half of the subjects received
task 4 prior to task 5 and half received task 5 prior to task 4.

For the bimanual handwriting tasks, the subject sat at a table
with one pencil in each hand. Subjects were told that they would
have to write the digits from 1 to 12 and the letters from A through
L with both hands simultaneously, and that they would be prevented
from seeing their hands.

Subjects were instructed to write the digits and letters as
quickly as possible without going off the sides or bottom of the
page. A card was placed about 10 inches above the writing surface so
that the subject could not see the digits or letters being written.
The data from the handwriting task were scored by raters who were
blind to the hypotheses. Each individual digit in a column was
rated against a standard Artype transfer digit (10 mm high) arranged
in a column from one to twelve and a standard Artype transfer letter

(10 mm high) arranged in a column from A through L. Each column of

36

written digits and letters was mounted on poster board in order to

minimize any obvious cues that they were written by the left or right

hand.

Raters received training sessions during which they practiced

scoring according to nine criteria.

Each digit and letter was rated against its Artype standard on

each of nine criteria by subtracting points from an assigned score

of 15 depending on the rater's judgement of the following dimensions:

1) Alignment. One point deducted if a digit or letter deviated

2)

3)

4)

5)

6)

7)

8)

from the general alignment of the symbols in a column by at

least 1 cm.

Scatter, compactness. One point deducted if spacing of the

elements of double digits was judged to sufficiently
deviate from its Artype.

Incompleteness. One to three points deducted for each
deviation from the Artype.

Excess structure. One to three points deducted for each
excess structure attached to the symbol.

Orientation, slant. One to two points deducted for 10 to
45 degree slant and an additional point deducted if greater
than 45 degrees.

Legibility. One point deducted if the symbol was
illegible.

Contour. One to two points deducted if symbol was judged
to sufficiently deviate from Artype contour and roundness.

Overlap. One point deducted if the symbol overlapped

37

another symbol in the column.
9) Pressure. One point deducted if the symbol was lighter
than that simultaneously written with the other hand.

Criterion nine was scored last, since a direct comparison
between the left and right hand digit or letter was required.

Concurrent speech and bimanual handwriting of digits and letters
was assessed using the same procedure as the traditional handwriting
task except that the subject was instructed to count aloud from 1 to
12 and to say the letters aloud from A through L while writing.

During tasks 4 and 5, bimanual handwriting was assessed using
the same procedure .as described for tasks 1 to 3 except without
concurrent speech. In addition, subjects were instructed to think
about their left hand or their right hand performance depending on
the allocate left or allocate right tasks. Half of the subjects
received instructions to bimanually write and allocate attention to
the left hand first then to repeat the procedure while allocating
attention to the right hand. The remaining subjects received the
opposite instructions, i.e., allocate right followed by allocate
left. This distribution of tasks 4 and 5 was used so as to control
for a possible order effect in comparing performance during
lateralized attending and concurrent bimanual writing.

Concurrent speech and unimanual sequential finger tapping.

 

On the unimanual sequential tapping test, subjects were instructed to
tap with each hand separately during each of two 30-second practice

trials. Each subject was instructed to start with the index finger

38

and tap outward to the little finger and then to start a new
sequence. The subject was instructed to tap as fast as possible
without making any sequential errors while tapping.

Test trials were randomly distributed (see Table l) and required
the subject to unimanually sequence with the left and right hand
separately in four conditions: 1) silent tapping without auditory
feedback of tones; 2) silent tapping with auditory tone feedback with
individual fingers having different frequency tones; 3) tapping while
saying aloud the lyrics of "Twinkle, twinkle, little star"; and 4)
tapping while spontaneously telling a story about stimulus card
picture drawings from a semi—projective test of Engagement Style
(McKinney, 1980) which were placed on the platform approximately 12
inches from the subject's face and in such a position as to prevent
the subject from seeing his fingers. The eight stimulus picture
cards were randomly assigned across subjects. The stimulus picture
cards used to elicit spontaneous generative speech were drawings from
McKinney's semi—projective Test of Engagement Style (McKinney,
1980). They depicted two boys in a variety of settings and
participating in activities typical for children of approximately
age 10. The stimulus pictures were drawn to depict children
approximately 10 years old. The subject was instructed to tell a
story about what might be happening in the stimulus picture.

Unimanual sequential finger tapping rate and accuracy was scored
and the measures used in later analysis for each of the 32 lS—second

trials were total sequential tapping rate, correct sequential

39

Table 1
Experimental Design Used to Investigate Speech Fluency and Tapping
in Childhood Stutterers 3nd Nonstutterers. Task 1=Si1ent Tapping;
Task 2= Tone Feedback Tapping; Task 3: Rhythmic Speech—Tapping;

Task 4: Spontaneous Speech-Tapping.

 

 

Subject Subject
Condition A n1 n2 n3 n4 Condition B n5 n6 n7 n8
Left, Right 1 2 3 4 Right, Left 1 2 3 4
2 4 1 3 2 4 l 3
3 1 4 2 3 l 4 2
4 3 2 1 4 3 2 1
Left, Right 2 1 4 3 Right, Left 2 1 4 3
4 2 3 1 4 2 3 1
l 3 2 4 1 3 2 4
3 4 l 2 3 4 1 2
Right, Left 4 3 2 1 Left, Right 4 3 2 l
3 l 4 2 3 1 4 2
2 4 1 3 2 4 l 3
l 2 3 4 1 2 3 4
Right, Left 3 4 1 2 Left, Right 3 4 1 2
1 3 2 4 1 3 2 4
4 2 3 l 4 2 3 1
2 l 4 3 2 1 4 3

40

tapping, and sequential error rate. Sequential error rate is the
difference between total and correct sequential tapping rate per
trial.

Speech fluency. Pretest speech fluency was assessed prior to
the concurrent speech and unimanual tapping task described above.
Fluency was assessed using the Riley Stuttering Severity Instrument
(Riley, 1980). The subjects were asked to read aloud age—appropriate
materials from the reading booklet of the Durrell Analysis of Reading
Difficulty (Durrell & Catterson, 1980) for later analysis of oral
reading fluency. In addition, to elicit spontaneous speech for
analysis of fluency, subjects were shown stimulus picture cards from
the same semi-projective test of Engagement Style described above
(McKinney, 1980) with different picture cards than those used during
concurrent tasks.

All speech was recorded on a Panasonic tape recorder for later
analysis of speech fluency by scoring the total number of
disfluencies and calculating a percentage of fluency. In addition to
oral reading and spontaneous speech tasks, subjects were asked to
repeat the words of the song "Twinkle, twinkle, little star" as a
rhythmic speech task, which was also scored for fluency percentage.

Speech during sequential tapping was recorded and scored for
total number of disfluencies and fluency percentage. In addition, 10
separate disfluency criteria were scored in an attempt to
differentiate stuttering from normal and developmental disfluency.

The ten criteria were: airflow breaks between repeated or prolonged

41

syllables, audible prolongations, vowel substitutions in repeated
syllables, tense surges during repetitions or prolongations,
part-word repetitions, whole-word repetitions, phrase repetitions,
interjections, revisions, and disrhythmic phonation.

Emotional stress questionnaire. Each subject was asked to
respond to 34 questions related to interpersonal and emotional stress
and specifically designed to measure social confidence and self
esteem, audience sensitivity, and social interest or sociability.
The subject was instructed to respond by pointing to his answer on a
response board that had the numbers from 1 to 5 and the following
description below each number: 1) no, never; 2) sometimes; 3)
middle amount; 4) quite a bit; 5) yes, always. (See appendix C for
34 item questionnaire.)

The current study consisted of eight separate instruments. The
total time required for administration was approximately 50 to 60
minutes.

Data analysis. Initially, analysis of variance (Speech Group
(2) by Age Group (3)) was used to ascertain whether stutterers and
nonstutterers differed on the five bimanual handwriting tasks.

Analysis of variance (Speech Group (2) by Age Group (3)) was
then performed on speech fluency measures including rhythmic speech,
spontaneous speech, and oral reading adapted from the Riley
Stuttering Severity Instrument (Riley, 1980).

Analysis of variance of concurrent speech and unimanual

sequential finger tapping was performed using BALANOVA. The repeated

42

measures (within-subjects) in the BALANOVA analysis were total speech
fluency percentage, ten individual speech disfluency criteria
percentages, total sequential tapping rate, correct sequential
tapping rate, and tapping error rate.

Finally, analysis of variance (Speech Group (2) by Age Group
(3)) was performed to determine whether stutterers and nonstutterers
differed on the emotional stress questionnaire total score. The
questionnaire data were then factor analyzed using PACKAGE (Hunter &
Cohen, 1969), a sequence of routines that involve eXploratory and
confirmatory factor analysis. In PACKAGE, exploratory factor
analysis is used to estimate the minimum number of underlying
dimensions measured by the items contained in the instrument. Then
the hypothesized dimensions are submitted to confirmatory factor
analysis. Each item is assigned a loading factor that is the
correlation of that item with other items in the dimension. A
loading factor of more than .50 indicates that the item is a reliable
measure of the dimension. The grouping of items in a dimension is
confirmed by the standard score coefficient alpha (ssca). A
dimension with an ssca of greater than .50 is considered to be
reliable. Following the confirmatory factor analysis, an analysis of

variance of the mean dimension scores was performed.

43

RESULTS

The results will be presented in the following order: bimanual
handwriting (handwriting organization and mirror-image reversals);
unimanual sequential tapping (sequential tapping rates, correct
tapping sequences, and tapping error rates); speech fluency (pretest
speech tasks and speech during tapping tasks); speech disfluency
during tapping (airflow breaks, audible prolongations, vowel
substitutions, tense surges, part-word repetitions, whole—word
repetitions, phrase repetitions, interjections, revisions and
disrhythmic phonations); emotional stress questionnaire (total
questionnaire score _and factor analysis).
Bimanual Handwriting

Handwriting organization. Analysis of variance of the
mean organization scores for each hand revealed significant between-
speech group differences in performance during each of the five
handwriting tasks. During performance of five tasks, there were
significant interactions with subject age group. Table 2 through
Table 6 summarize the results of the analysis for handwriting
organization during the five handwriting tasks. As shown in Table 2,
when compared to nonstutterers, stutterers had significantly poorer
dominant right hand performance for letters when no speech or
lateralized attending was required. A speech group by age group
interaction [F(2,29)=3.37, p“.04] suggests that youngest stutterers
(age 6 to 8.11) performed more poorly with the right hand than did

older stutterers when writing letters. In addition, a speech group

44

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45

by age interaction [F(2,29)=3.53, p“.04] suggests that the youngest
group of nonstutterers had significantly poorer left hand performance
for letters than the older nonstutterers.

The results of Task 2 (Task 1 replication) are summarized in
Table 3 and indicate replication of findings from Task 1, except that
in Task 2 there were no significant differences between stutterers
and nonstutterers in right hand performance. During Task 2, when
writing digits with the right hand, younger stutterers performed more
poorly than older stutterers [F(2,29)=7.65, p-(.002]. Also during
Task 2, when writing letters with the left hand, younger
nonstutterers performed more poorly than older nonstutterers
[F(2,29)=5.75, p‘.008].

The results of Task 3, (bimanual handwriting with concurrent
vocalization of each digit or letter) are summarized in Table 4. No
significant between speech group differences occurred during this
task. There were, however, speech group by age group interactions.
When writing letters with the right hand, younger stutterers
performed more poorly than older stutterers [F(2,29)=4.41, p < .02].
In addition, during left hand performance for letters, younger
stutterers performed more poorly than older stutterers [F(2,29)=7.02,
p A‘.OO3] and younger nonstutterers performed more poorly than older
nonstutterers [F(2,29)=3.67, p ‘.O4].

The results of Task 4, (bimanual handwriting with lateralized
attending to the left hand) are summarized in Table 5. Across all

age groups, stutterers performed more poorly than nonstutterers in

46

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49

right hand performance for digits. In addition, during Task 4,
across all age groups, stutterers performed more poorly than
nonstutterers in left hand performance for letters. Younger
stutterers and nonstutterers did not differ significantly in left
hand performance for letters. However, the oldest age group of
stutterers performed more poorly than the nonstutterers during this
task. Also during this task, younger stutterers had significantly
poorer performance than older stutterers in right hand performance
for digits [F(2,29)=3.64, p‘<.04], left hand performance for digits
[F(2,29)=5.46, p {{.01] and right hand performance for letters
[F(2,29)=4.37, p 4.02]. The three age groups of stutterers did not
differ during left hand performance for letters. Finally, younger
nonstutterers performed more poorly than older nonstutterers in
left hand performance for digits '[F(2,29)=9.98, p <. 0006] and
left hand performance for letters [F(2,29)= 14.06, p d‘.0001].

The results of Task 5, (bimanual handwriting with lateralized
attending to the right hand) are summarized in Table 6. Across all
age groups, stutterers performed more poorly than nonstutterers in
left hand performance for digits and letters with no significant
between speech group differences in right hand performance. Also
during Task 5, younger stutterers had significantly poorer
performance than older stutterers in right hand performance for
digits [F(2,29)= 4.39, p <.02], and left hand performance for
digits [F(2,29)= 6.24, p ‘.005]. The three age groups of

stutterers and nonstutterers did not differ in left hand performance

50

51

 

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for letters. In addition, during Task 5, younger nonstutterers
performed more poorly than older nonstutterers in left hand
performance for digits [F(2,29)= 6.51, p (.005] and left hand
performance for letters [F(2,29)= 4.82, p 4(.01].

Relevant to the hypothesis about bimanual handwriting
organization, across all writing tasks, stutterers did have poorer
handwriting organization with their nondominant left hand. In
addition, during the traditional bimanual handwriting task (Task 1),
stutterers, as compared to nonstutterers, had significantly poorer
dominant right hand performance and this can be attributed to the
youngest age group of stutterers (age 6 to 8.11). During Task 2,
(replication of Task 1 representing practiced performance) stutterers
and nonstutterers did not differ in right hand performance.

During concurrent vocalization and bimanual writing, no
significant differences occurred between stutterers and
nonstutterers. However, younger stutterers' left hand organization
was more disorganized than older stutterers and more disorganized
than on Task 1 and Task 2.

Both tasks (Task 4 and 5) involving lateralized allocation of
attention produced more disruption in stutterers than in
nonstutterers. Specifically, during Task 4 (allocation of attention
to the left hand), compared to nonstutterers, stutterers had
significantly poorer right hand and left hand performance. This task
was most disruptive for stutterers and was slightly more disruptive

than the other bimanual tasks for the Youngest nonstutterers compared

52

A.

M

iii

to the older nonstutterers.

During Task 5 (allocation of attention to the right hand),
compared to nonstutterers, stutterers had significantly poorer left
hand performance with no speech group differences in right hand
performance.

Mirror-image reversals. Table 7 summarizes the results of
the analysis for reversals during bimanual handwriting across five
tasks, including right and left hand reversals of digits and letters.
As indicated in Table 7, compared to nonstutterers, the three age
groups of stutterers had significantly more reversals across all five
bimanual handwriting tasks. The results of the age group comparisons
suggest that stutterers had significantly more reversals than
nonstutterers in the two older age groups, i.e., 9 to 11.11 and 12 to
15. The youngest age group of stutterers and nonstutterers (6 to
8.11) did not differ significantly in the presence of reversals
during bimanual handwriting. The youngest group of nonstutterers had
significantly more reversals than the older nonstutterers [F(2,29)=
25.53, p 4‘.0001], whereas the three age groups of stutterers did not
differ significantly in the number of reversals.

Tables 8 through 12 summarize the results of the analysis
for reversals during each of the five bimanual tasks. The results of
the analysis for reversals during Task 1 are summarized in Table 8.
Across all age groups, stutterers had significantly more reversals
than nonstutterers in left hand performance for digits and letters
with no significant between speech group differences in right hand

53

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performance. During Task 1, the youngest group of stutterers and

nonstutterers did not differ in reversals in left hand performance
for digits or letters. Also during Task 1, younger nonstutterers had
significantly more reversals than older nonstutterers in left hand
performance for digits [F(2,29)= 19.65, p 4.0001] and left hand
performance for letters [F(2,29)= 6.76, p <.004]. There were no
significant between age group differences in reversals for
stutterers.

The results for reversals during Task 2 (Task 1 replication) are
summarized in Table 9. The results from Task 2 agreed with those
of Task 1 except that the youngest group of stutterers and
nonstutterers did not differ in reversals for digits. However,
nonstutterers across age groups had significantly fewer left hand
reversals of letters. In addition, younger stutterers had
significantly more reversals than older stutterers in right hand
performance for digits [F(2,29)= 4.88, p 4.01] with no other between
age group differences in right or left hand performance for
stutterers.

The results for reversals during Task 3 are summarized in Table
10. Task 3 replicated the findings that stutterers had significantly
more reversals than nonstutterers in left hand performance for digits
and letters with no significant between speech group differences in
right hand performance. However, during Task 3, younger
nonstutterers had significantly more reversals than older

nonstutterers in right hand performance for digits [F(2,29)= 4.73,

56

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58

p (.02] and in right hand performance for letters [F(2,29)= 5.21,
p i4 .01] in addition to the consistent finding across tasks of
younger stutterers having more reversals than older nonstutterers in
left hand performance. Also during Task 3, younger stutterers had
more reversals in right hand performance for digits than did older
stutterers [F(2,29)= 4.22, p < .03].

The results for reversals during Task 4 are summarized in Table
11. This task (bimanual writing with allocation of attention to the
left hand) replicated previous task findings of more reversals in
left hand performance for stutterers compared to nonstutterers.
However, during this task stutterers also had significantly more
reversals than nonstutterers in right hand performance for letters
across age groups. In addition, this task was most disruptive for
the youngest age group of stutterers and nonstutterers. As occurred
in Task 3, the youngest nonstutterers had more reversals than older
nonstutterers in right hand performance for digits [F(2,29)=
4.46, p < .02] and letters [F(2,29)= 4.23, p 4 .04]. In addition,
younger stutterers had significantly more reversals than older
stutterers in right hand performance for digits [F(2,29)= 4.21,
p < .03] and letters [F(2,29)= 5.21, p 4.01]. It is important to
note that younger nonstutterers have consistently more reversals in
left hand performance than older nonstutterers. However, younger
stutterers and older stutterers do not differ in left hand mirror

image reversals.

The interesting finding resulting from Task 5 (allocation of

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60

attention to the right hand) is the similarity to findings from the
traditional bimanual handwriting task i.e., Tasks 1 and 2 (see
Table 12). Across all age groups, stutterers had more reversals
than nonstutterers in left hand performance with no between speech
group differences in right hand performance. The youngest group of
stutterers and nonstutterers did not differ in left hand reversals
whereas the younger nonstutterers had more reversals in left hand
performance than the older nonstutterers. Also, younger stutterers
had more reversals than older stutterers in right hand performance
for digits [F(2,29)= 5.03, p (.01].

These bimanual writing results confirm the hypothesis of greater
frequency of mirror image reversals with the nondominant hand in
stutterers. Across all age groups, tasks, and hand performance,
stutterers had more mirror image reversals than nonstutterers.
However, across tasks and hand performance the 6 to 8.11 year old
stutterers and nonstutterers did not differ in reversals due to the
high frequency of reversals in the youngest nonstutterers. Across
tasks and hand performance, the three age groups of stutterers did
not differ in the frequency of reversals.

Consistent findings during each of the five bimanual tasks were
as follows: across age groups, stutterers had significantly more
reversals than nonstutterers in left hand performance. However, the
youngest group of stutterers and nonstutterers did not differ in left
hand reversals; younger nonstutterers had significantly more

reversals than older nonstutterers in left hand performance; and the

61

 

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62

three age groups of stutterers did not differ in left hand mirror
image reversals. All of these consistent findings concern mirror
image reversals in left hand performance.

Results not predicted were mirror image reversals in right hand
or dominant hand performance. There was only one task in which
stutterers had more reversals in right hand performance when compared
to nonstutterers. This difference occurred during bimanual writing
of letters while allocating attention to the left hand.

With the exception of Task 1 (traditional bimanual writing), all
tasks resulted in younger stutterers (age 6 to 8.11) having more
right hand reversals of digits than older stutterers (9 to 15).
Task 4 (bimanual writing with allocation of attention to the left
hand) produced the greatest frequency of right hand mirror image
writing, particularly in the Youngest subjects. During Task 4,
younger nonstutterers had significantly more reversals than older
nonstutterers in right hand digits and letters. In addition, younger
stutterers had more reversals than older stutterers in right hand
digits and letters.

One other task (Task 3, bimanual writing and concurrent speech)
produced right hand mirror image writing in nonstutterers. During
Task 3, younger nonstutterers age 6 to 8.11, had more right hand
reversals of digits and letters than older nonstutterers age 9 to 16.

Overall, there appears to be a similarity between certain
bimanual tasks and possibly between underlying mechanisms. Task 1

(traditional bimanual handwriting). task 2 (Task 1 replication), and

63

Task 5 (lateralized attending to the right hand) produced similar
results in mirror image writing. Perhaps the traditional bimanual
task actually involves the lateral gradient of attention to the right
hand in a right-handed population, with minimal involvement of the
right hemisphere or interhemispheric processing. In contrast, Task 3
(concurrent speech and bimanual writing) and Task 4 (lateralized
attending to the left hand) produced more right hand reversals
particularly in the children aged 6 to 8.11, possibly activating
right hemisphere involvement and the need for interhemispheric
efficiency.

The results of. the current study suggest that developmental
mechanisms supporting right hemisphere activation and inhibition via
interhemispheric communication mature around age 9. In stutterers, 4
our of S bimanual tasks produced more right hand mirror writing in
younger stutterers than in older stutterers, suggesting that
stutterers age 6 to 9 years have particular difficulty in right
hemisphere activation and interhemispheric processing of speech and
language. In that right hand mirror writing occurred in the
youngest stutterers during traditional handwriting replication and
allocation of attention to the right hand, inefficient motor lead
control from the left hemisphere might also be implicated in this
group.

Unimanual Sequential Tapping

Sequential tapping, rates. Analysis of variance revealed

significant main effects for Age [F(l,54)= 12.79, p ‘ .0005] and

64

Hand—Used-For—Tapping [F(l,54= 4.43, p 4.04]. The mean sequential
tapping rates for these main effects are shown in Table 13. Tapping
rates increased with age and the right hand had a significantly
faster tapping rate than the left hand. Analysis of variance also
revealed a significant main effect for Task [F(3,l62)= 11.93,
p ‘.0005]. Interpretation of the Task main effect, however, must be
considered in relation to a significant Trial Block by Task
interaction [F(9,486)= 2.86, p < .0003]. The mean sequential
tapping rates for this task main effect and interaction are shown in
Table 14. Sequential tapping rates increased over Trial Blocks
during tapping concurrent with tone feedback of each key tapped.
Without tone feedback, tapping rates either did not increase or in
the case of tapping concurrent with rhythmic speech, rates decreased
over Trial Blocks.

Correct tapping, sequence. Analysis of variance revealed
significant main effects for Speech Group [F(l,54)= 11.99,
p ( .0001], for Age [F(1,54)= 14.75, p {.0005}, and Hand-Used—For-
Tapping [F(l,54)= 6.46, p (.01]. Mean correct tapping sequences for
these main effects are shown in Table 15. Stutterers had
significantly fewer correct tapping sequences than nonstutterers.
Mean correct tapping sequences increased with age and the right hand
had significantly more correct tapping sequences than the left hand.
Analysis of variance also revealed a significant main effect for Task
[F(3,l62)= 11.64, p <'.0005]. Interpretation of the Task main
effect, however, must be considered in relation to a significant

65

Table 13

Mean Sequential Tapping Rates for Age and
Hand-Used—For-Tapping Main Effects

Age Mean Score per Trial
6-8.11 years 20.29
9-11.11 years 24.20
12-15 years 29.09

Hand-Used-For—Tapping

Right Hand 24.80
Left Hand 24.20

66

Table 14

Mean Sequential Tapping Rates for Task Main Effect

and Trial Block by Task Interaction

Task

Silent Tapping

Tone Feedback Tapping
Rhythmic Speech Tapping
Spontaneous Speech Tapping

Silent Feedback
Trial Block
1 24.72 25.37
2 25.72 26.02
3 25.63 26.75
4 25.11 28.20

67

Mean Score per Trial

25.30
26.60
23.46
22.76

Rhythmic

23.91
24.21
23.07
22.63

Spontaneous

21.44
23.93
23.00
23.09

Table 15

Mean Correct Tapping Sequences for Speech Group,
Age, and Hand—Used-For-Tapping Main Effects

Speech Group Mean Score per Trial
Stutterers 19.19
Nonstutterers 23.60

Age
6—8.11 years 17.28
9—11.11 years 21.20
12-15 years 25.70

Hand—Used-For—Tapping

Right Hand 21.70
Left Hand 21.10

68

Trial Block by Task interaction [F(9,486)= 2.99, p 4 .002]. The
mean correct tapping sequences for the Task main effect and
interaction are shown in Table 16. Correct tapping sequences
increased over Trial Blocks during tapping concurrent with tone
feedback. During silent tapping and tapping concurrent with speech,
correct tapping sequences initially increased and then decreased over
Trial Blocks.

Tapping ‘ggggg. Iggggi. Analysis of variance revealed
significant main effects for Speech Group [F(1,54)= 56.95,
p 4 .0005] and Task [F(3,l62)= 5.90, p 4.001]. The mean tapping
error rates per trial for each task (silent tapping = 3.12, tone
feedback tapping = 3.45, rhythmic speech = 2.87, spontaneous speech =
3.07) indicate fewest tapping errors occurred concurrent with
rhythmic speech and the highest frequency of tapping errors occurred
concurrent with tone feedback. Interpretation of the Speech Group
main effect, however, must be considered in relation to a significant
Speech Group by Age interaction [F(l,54)= 5.26, p < .008]. The
mean tapping error rates for the Speech Group main effect and
interaction are shown in Table 17. Stutterers had significantly
higher tapping error rates than nonstutterers. Tapping error rates
increased with age in stutterers and decreased with age in
nonstutterers.

Relevant to the hypothesis of greater frequency of sequencing
errors in stutterers compared to nonstutterers, stutterers had
significantly fewer correct tapping sequences and significantly

69

Table 16

Mean Correct Tapping Sequences for Task Main Effect
and Trial Block by Task Interaction

Task Mean Score per Trial
Silent Tapping 22.15
Tone Feedback Tapping 23.13
Rhythmic Speech Tapping 20.58
Spontaneous Speech Tapping 19.68
Silent Feedback Rhythmic Spontaneous
Trial Block
1 21.71 22.05 20.84 18.42
2 22.69 22.62 21.25 20.70
3 22.48 23.38 20.38 19.87
4 21.69 24.50 19.84 19.74

70

Table 17

Mean Tapping Error Rates for Speech Group
Main Effect and Speech Group by Age Interaction

Speech Group

Stutterers
Nonstutterers

Age

6-8.ll years
9-11.11 years
12—15 years

Mean Score per Trial

4.14
2.11
Stutterers Nonstutterers
3.45 2.54
4.10 1.96
4.88 1.80

71

higher tapping error rates than nonstutterers. The Speech Group by
Age interaction of tapping error rates, suggests tapping error rates
increased with age in stutterers and decreased with age in
nonstutterers. This study suggests that normal boys between the age
of 12 to 15 years have maximum capability for rapid and correct
unimanual sequencing compared to younger boys, with children age 6
to 9 having the slowest tapping rate and the fewest correct
sequences. There appears to be a linear improvement in tapping rate
and accuracy between the ages of 6 and 15. It would appear that
stutterers and nonstutterers do not differ on the rapidity of
sequential tapping. However, accuracy of the sequencing seems to be
less for stutterers. Unimanual sequencing could meet the need for
establishing potential differences between stutterers and
nonstutterers in the area of motor and speech timing control
(Tingley & Allen, 1975), if individual performance was monitored to
assess possible manual sequential timing control difficulties. Given
that across all subjects, the right hand had more rapid and accurate
sequential tapping than the left hand, and that stutterers had as
rapid a rate as nonstutterers, but fewer correct sequences, one might
speculate than the errors in right hand sequencing might have
produced the signficantly lower, correct sequencing rate in
stutterers. This finding supports the hypothesis of a superior left
hemisphere ability for manual sequencing in normal speaking
right-handed children and a left hemisphere role in the disruption
of sequencing found in right-handed stutterers.

72

Relative to the type of task during concurrent unimanual
sequential tapping, results suggest that during the experiment there
was an increase in the rate of tapping and in the number of correct
sequences while tapping with audible tone feedback for each finger
tapped. However, throughout the experiment the tone feedback tasks
produced the most tapping errors. The rhythmic speech task actually
slowed the rate of tapping during the experiment and was also
associated with the fewest tapping errors. The imposed rhythm and
external timing control of the rhythmic speech task probably improved
accuracy of unimanual sequencing in all subjects.

Speech Fluency

Pretest speech tasks. As indicated in Table 18, across age
groups stutterers were significantly more disfluent than
nonstutterers during rhythmic speech, oral reading, and spontaneous
speech. During rhythmic speech, the youngest and oldest age groups
of stutterers and nonstutterers did not differ significantly in
speech fluency.

Speech during tapping tasks. Analysis of variance on data
obtained from the experimental concurrent speech tasks revealed
significant main effects for Speech Group [F(l,54)= 45.97,
p (.0005], Age [F(l,54)= 3.22, p ‘.05], Trial Block [F(3,l62)=
2.71, p (.05], and for Task [F(1,54)= 97.31, p (.0005]. The mean
percent speech fluency scores for these main effects are shown in
Table 19. Interpretation of the main effects, however, must be

considered in relation to a Task by Speech Group interaction

73

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Table 19

Percent Mean Speech Fluency During Tapping for Speech Group,
Age, Trial Block and Task Main Effects

SPEECh GFOUP Mean Score per Trial
Stutterers 92.7
Nonstutterers 98.0
Age
6 to 8.11 years 94.0
9 to 11.11 years 95.8
12 to 15 years 96.2

Trial Block

1 95.1
2 94.6
3 96.0
4 96.0
Task
Rhythmic Speech 97.8
Spontaneous Speech 92.8

75

[F(l,54)= 132.19, p 4 .001], and a Task by Speech Group by Age by
Hand-Used-For—Tapping interaction [F(l,54)= 3.26, p < .04]. The
mean percent speech fluency scores for these interactions are shown
in Table 20. Stutterers were more disfluent than nonstutterers
during concurrent speech tasks. However, examination of the mean
scores in Table 20 suggests the difference in speech fluency between
stutterers and nonstutterers is most significant during spontaneous
speech. Speech fluency increased with age, particularly during
spontaneous speech. In addition, speech fluency increased over
experimental trials. In relation to Hand-Used—For-Tapping, Table 20
suggests that speech fluency was equal to or slightly lower in
nonstutterers while tapping with their right hand as compared to
their left hand during spontaneous speech but not during rhythmic
speech. In stutterers, speech fluency was slightly lower while

tapping with their left hand as compared to their right hand for

spontaneous and rhythmic speech.
Speech Disfluencies During Tapping

Additional analysis of variance was performed on ten distinct
speech disfluency criteria: airflow breaks between repeated or
prolonged syllables; audible prolongations; vowel substitutions in
repeated syllables; tense surges during repetitions or prolongations;
part—word repetitions; whole-word repetitions; phrase repetitions;
interjections, revisions, and disrhythmic phonations.

Airflow breaks. Analysis of variance revealed a significant

main effect for Speech Group [F(l,54)= 6.17, p < .01]. Stutterers

76

Table 20

Percent Mean Speech Fluency During Tapping for
Task by Speech Group and Task by Speech Group
by Age by Hand-Used—For—Tapping Interactions

Speech Group Rhythmic Spontaneous

Stutterers 96.2 89.0

Nonstutterers 99.4 96.3
Rhythmic Spontaneous

Right Hand Left Hand Right Hand Left Hand

Stutterers
6 to 8.11 yrs. 94.9 94.5 88.3 86.0
9 to 11.11 yrs. 97.5 96.7 88.5 88.0
12 to 15 yrs. 97.3 96.3 92.0 89.5
Nonstutterers
6 to 8.11 yrs. 99.3 99.2 93.7 95.9
9 to 11.11 yrs. 99.6 99.6 95.5 96.9
12 to 15 yrs. 99.3 99.6 97.1 98.5

77

had significantly more breaks (.04) per trial than nonstutterers
(.002).

Audible prolongations. Analysis of variance revealed
significant main effects for Speech Group [F(l,54)= 20.62.
p ‘ .0005], and Task [F(l,54)= 9.86, p 4 .003]. Interpretation of
the main effects must be considered in relation to a Speech Group by
Task interaction [F(l,54)= 8.95, p (.004]. The mean scores for the
main effects and interaction are shown in Table 21. Stutterers had
significantly more audible prolongations than nonstutterers and more
audible prolongations occurred with spontaneous as compared to
rhythmic speech.

Vowel substitution. Analysis of variance revealed a
significant main effect for Speech Group [F(l,54)= 4.03,
p «(.05]. Stutterers had significantly more vowel substitutions per
trial (.047) than nonstutterers (0).

Tense surges. Analysis of variance revealed significant main
effects for Speech Group [F(l,54)= 33.99, p < .0005], and Task
[F(l,54)= 6.84, p < .01] and in addition, a Speech Group by Task
interaction [F(l,54)= 7.17, p <.01]. The mean scores for the main
effects and interaction are shown in Table 22. Stutterers had more
tense surges during spontaneous speech as compared to rhythmic
speech. Nonstutterers had more tense surges during rhythmic as
compared to spontaneous speech.

Part—word repetitions. Analysis of variance revealed main

effects for Speech Group [F(l,54)= 65.54, p 4.0005] and Task
78

Table 21

Mean Audible Prolongation Scores for Speech Group and Task
Main Effects and Speech Group by Task Interaction

Speech Group Mean Score per Trial

Stutterers .312

Nonstutterers .004

Task

Rhythmic Speech .072

Spontaneous Speech .244

Rhythmic Spontaneous

Stutterers .145 .480
Nonstutterers .000 .008

79

fin

Table 22

Mean Tense Surge Scores for Speech Group and Task
Main Effect and Speech Group by Task Interaction

Speech Group Mean Score per Trial

Stutterers .356

Nonstutterers .001

Task

Rhythmic Speech .107

Spontaneous Speech .251

Rhythmic Spontaneous

Stutterers .210 .502
Nonstutterers .003 .000

80

[F(l,54)= 44.97, p 4.0005]. Interpretation of the main effects
must be considered in relation to a Speech Group by Task interaction
[F(l,54)= 48.02, p 4.0005], and a Speech Group by Hand—Used-For-
Tapping interaction [F(l,54)= 5.24, p < .02]. The mean scores for
the main effects and interactions are shown in Table 23. Stutterers
had significantly more part-word repetitions during spontaneous as
compared to rhythmic speech. Nonstutterers had significantly more
part-word repetitions during rhythmic as compared to spontaneous
speech. In addition, stutterers had more part-word repetitions while
tapping with the left hand as compared to the right hand.
Nonstutterers had more part-word repetitions while tapping with the
right hand as compared to the left hand.

Whole-word repetitions. Analysis of variance revealed a main
effect for Task [F(l,54)= 9.92, p < .002]. There was not a main
effect for Speech Group, however, the main effect must be considered
in relation to a Speech Group by Task by Hand-Used-For-Tapping
interaction [F(l,54)= 5.49, p <.02]. Mean scores for the main
effect and interaction are shown in Table 24. Significantly more
whole—word repetitions occurred during spontaneous as compared to
rhythmic speech. During spontaneous speech, stutterers had more
whole—word repetitions while tapping with their left hand compared to
the right hand and nonstutterers had more whole-word repetitions
while tapping with the right as compared to the left hand. During
rhythmic speech, stutterers had more whole-word repetitions while

tapping with the right compared to the left hand.

81

Table 23

Mean Part-Word Repetition Scores for Speech Group and Task Main
Effects and Speech Group by Task and Speech Group
by Hand-Used-For-Tapping Interactions

Speech Group Mean Score per Trial
Stutterers .474
Nonstutterers - .009
Task
Rhythmic Speech .085
Spontaneous Speech .400
Rhythmic Spontaneous
Stutterers .156 .800
Nonstutterers .014 .003
Right Hand Left Hand
Stutterers .423 .524
Nonstutterers .020 .000

82

Table 24

Mean Whole-Word Repetition Scores for Task Main Effect and
Speech Group by Task by Hand—Used-For-Tapping Interaction

Task

Rhythmic Speech
Spontaneous Speech

Rhythmic Right Hand
Left Hand

Spontaneous Right Hand
Left Hand

Mean Score per Trial

.056
.200
Stutterers Nonstutterers
.130 .031
.033 .034
.224 .155
.313 .078

83

Phrase repetitions. Analysis of variance revealed a main
effect for Task [F(l,54)= 11.96, p 4:.001]. Significantly more
phrase repetitions occurred during spontaneous speech (.10) compared
to rhythmic speech (.027). There was no main effect for Speech
Group. In addition, there was an Age by Hand-Used-For—Tapping
interaction [F(l,54)= 3.08, p 4 .05]. The mean scores for this
interaction are shown in Table 25. Phrase repetitions decreased as
age increased. For the two older age groups, more phrase repetitions
occurred while tapping with the right compared to the left hand. For
the youngest group (6 to 8.11 years), more phrase repetitions
occurred while tapping with the left compared to the right hand.

Intepjections. Analysis of variance revealed a significant
main effect for Task [F(l,54)= 18.97, p < .0005]. Interjections
were more likely to occur during spontaneous speech (.343) compared
to rhythmic speech (.029). There was not a main effect for Speech
Group.

Revisions. Analysis of variance revealed a significant main
effect for Task [F(l,54)= 21.15, p < .0005]. Interpretation of this
main effect must be considered in relation to a Task by Hand-Used-
For-Tapping interaction [F(l,54)= 4.24, p < .04]. Mean scores for
the main effect and interaction are shown in Table 26. Significantly
more revisions occurred during spontaneous compared to rhythmic
speech. During spontaneous speech, more revisions occurred while

tapping with the right compared to the left hand.

84

Table 25

Mean Phrase Repetition Scores for the Age

by

Age

6-8.11 years
9-11.11 years
12—15 years

Hand—Used-For-Tapping Interaction

Right Hand

.098
.056
.040

85

Left Hand

.140
.000
.000

Table 26

Mean Revision Scores for the Task Main Effect and
Task by Hand-Used—For—Tapping Interaction

Task Mean Score per Trial
Rhythmic Speech .096
Spontaneous Speech .252

Right Hand Left Hand
Rhythmic Speech .087 .110
Spontaneous Speech .301 .202

86

Disrhythmic phonations. Analysis of variance revealed no
significant effects.

Relevant to the hypothesis concerning demand for spontaneous
speech and a greater increase in disfluency in stutterers than in
nonstutterers, speech during tapping tasks resulted in more
spontaneous speech disfluency in stutterers than nonstutterers. In
addition, spontaneous speech fluency increased with age. Spontaneous
speech also resulted in more within—word fragmentation in stutterers
than in nonstutterers. The results of the ten distinct disfluency
criteria during concurrent performance suggest that childhood
stutterers as compared to nonstutterers have more airflow breaks,
audible prolongations, vowel substitutions, tense surges and
part-word repetitions. In contrast and relevant to discussion of
normal developmental disfluency, childhood stutterers and
nonstutterers did not differ in whole-word repetitions, phrase
repetitions, interjections, revisions or disrhythmic phonations.
It appears then that childhood stutterers can be differentiated
from nonstutterers on the basis of within-word fragmentation.

Spontaneous speech also produced more disfluencies than
rhythmic speech, specifically more audible prolongations, tense
surges, part-word repetitions, whole-word repetitions, phrase
repetitions, interjections, and revisions. Spontaneous generative
speech is therefore disruptive across type of disfluency in both
stutterers and nonstutterers.

Relevant to developmental disfluency, speech fluency

87

increased as age increased, and in addition, phrase
repetitions which are likely to be considered normal
disfluency, decreased as age increased.

The relationship between speech fluency and lateralized
performance can be addressed based on the result of stutterers being
more disfluent while tapping with the left hand compared to the right
hand. Specifically, istutterers had more part-word repetitions and
whole—word repetitions while sequentially tapping with the left hand
as compared to the right hand. This would suggest an overload of the
motor programming and temporal sequencing systems when the right
hemisphere is activated for sequencing. This could occur through
right hemsiphere inefficiency for motor sequencing or through
inefficient interhemispheric communication.

For nonstutterers, results of speech fluency during tapping
suggest that normal speaking children were more disfluent while
tapping with the right hand as compared to the left hand.
Specifically, nonstutterers had more part—word repetitions,
whole—word repetitions, and phrase repetitions while tapping with
the right hand compared to the left. The exception to this was the
youngest group (age 6 to 8.11 years) who did not differ between hands
in the occurrence of phrase repetitions.

It would seem then, that in normal speaking children, time
sharing tasks involving speech and unimanual sequencing, support the
left hemisphere as the active hemisphere in temporal sequencing,

whereas in stutterers, the right hemisphere is more involved and

probably in an inefficient way.

88

Emotional Stress Questionnaire

Total qpestionnaire score. The emotional stress questionnaire
total score was designed to measure interpersonal and emotional
stress. High scores indicate high interpersonal and emotional
stress. Analysis of variance of the total score revealed
significant differences between speech groups [F(l,58)= 13.45,
p ( .0005]. The mean score was 93.63 for stutterers (SD= 14.5), and
81.67 for the nonstutterers (SD= 10.5). As indicated in Table 27,
stutterers in each of three age groups had significantly higher
questionnaire scores than nonstutterers.

Factor analysis, Factor analysis of the questionnaire
items was performed for all items combined. This analysis revealed
three separate and reliable dimensions which were labelled: Audience
Sensitivity (§§Eé?°74)v Social Confidence (§§g§;.77), and
Sociability (§§E§F.65). Analysis of variance of mean dimension
scores indicated that stutterers had higher Audience Sensitivity
[F(l,58)= 15.0, p 4 .0003], lower Social Confidence [F(l,58)=
28.4, p ‘C .0005], and lower Sociability [F(l,58)= 13.81,
p 4 .0005] when compared to nonstutterers. As shown in Table 28,
stutterers in each of three age groups had significantly lower Social
Confidence than nonstutterers. However, on the dimensions of
Audience Sensitivity and Sociability, some of the age groups did not
differ. Stutterers and nonstutterers age 9 to 12 years did not
differ in Audience Sensitivity. However, the youngest and oldest

group of stutterers had significantly higher Audience Sensitivity

89

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than nonstutterers. 0n the sociability dimension, the youngest group
of stutterers and nonstutterers did not differ. The older
group of stutterers (age 9 to 15 years) had significantly
lower sociability than the nonstutterers.

Confirmatory factor analysis with communalities was performed to
identify which items were more reliable measures of each dimension
for stutterers and nonstutterers. Table 29 shows the results of this
analysis: questionnaire items and their respective factor loadings
are ranked in order from the most to the least reliable measures of
the three dimensions for each group. For stutterers, the factor
analysis revealed ‘gggg reliabilities of .76 for Audience
Sensitivity, .84 for Social Confidence, and .72 for Sociability.
Reliabilities for each dimension for nonstutterers were .55 for
Audience Sensitivity, .43 for Social Confidence, and .55 for
Sociability.

Relevant to the hypothesis concerning higher emotional stress in
older stutterers compared to younger stutterers and all ages of
nonstutterers, the current results suggest the total ESQ score, or
general measure of emotional stress, differentiates stutterers from
nonstutterers regardless of age. However, individual dimensions
within the questionnaire proved to be valuable for differentiating
age groups of stutterers and nonstutterers. The one dimension that
seemed to affect all stutterers as compared to nonstutterers was
lower social confidence. The questionnaire item that most reliably

measures social confidence and self esteem for stutterers and

92

 

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nonstutterers is item number 28 ("Do you feel that you are as good
as the other children in your class?"). For the stutterers, the
next most reliable item concerns thinking of oneself as a failure.

In the area of social and audience sensitivity, the youngest and
oldest age groups of stutterers had the highest levels of audience
sensitivity. The questionnaire items that most reliably measure
audience sensitivity are item 7 ("Do you like to get up in front of
class and give a speech?"), and item 6 ("Do you like to talk in front
of class?"). The audience sensitivity scores remained relatively
consistent across ages for the nonstutterers. However, because of a
drop in audience sensitivity during the age period 9 to 12 in the
stutterers, this age group of stutterers and nonstutterers did not
differ.

In the area of sociability and social interest, the older age
groups of stutterers did have lower sociability and social interest
scores than the nonstutterers. The questionnaire items that most
reliably measure sociability are item 11 for stutterers ("Do you like
to meet new children?"), and item 14 for nonstutterers ("Do you like
to be around other children?"). The sociability scores remained
relatively consistent for all age groups of stutterers. However, the
youngest group of nonstutterers age 6 to 9 years had significantly
lower socialibity scores resulting in lack of significant differences
between stutterers and nonstutterers in this age group.

Although the Emotional Stress Questionnaire (ESQ) seems to be

particularly useful for stutterers, it might also be useful for

94

assessing speech and communication stress in normal speaking
children or in children with other communication or speech and

language disorders.

95

DISCUSSION

The results confirmed the prediction that, during bimanual
handwriting, right—handed school-aged stutterers compared to
nonstutterers have poorer left hand performance and greater frequency
of left hand mirror reversals. The study also confirmed the
prediction that during concurrent unimanual sequential tapping,
stutterers have more finger sequencing errors than nonstutterers.
Moreover, stutterers as compared to nonstutterers are more disfluent
during concurrent unimanual sequencing with the demand for
spontaneous speech causing a greater increase in disfluency and
within-word fragmentation in stutterers than in nonstutterers.
Finally, the results indicate that childhood stutterers compared to
nonstutterers have higher interpersonal and emotional stress.

The predictions for the current study were based to a large
extent on hypotheses derived from research with adult and childhood
stutterers and nonstutterers. The data from the current study that
fit the predictions best were those for the older subjects (age 9
years to 15 years old). The youngest group of stutterers and
nonstutterers (age 6 to 9 years) produced data that least fit the
predictions, particularly in the areas of bimanual handwriting and
emotional stress.

Bimanual Handwriting

Handwriting organization. The current findings support

previous research with adults (Fitzgerald et a1, 1984; Greiner et

al, 1984b) suggesting that stutterers' poorer nondominant hand

96

performance during bimanual writing may be due to inability of the
left hemisphere to inhibit activity of the right hemisphere.
The current findings with children support this hypothesis and give
evidence of lack of full left hemisphere motor lead control until
age 9 years, with young stutterers (age 6 to 9 years) having the
least left hemisphere motor lead control during bimanual tasks.

The current findings support the contention that
interhemispheric connections develop around age 9 at which time the
left hemisphere establishes motor output control; that is, until
age 9, there is poorly established inhibition of right hemisphere
actitivty. The maturation of the corpus callosum provides the
inhibition of competing right hemisphere activity necessary for
the development of left hemisphere motor control. Thus,
during bimanual handwriting tasks, the right hemisphere is
inhibited and the left hand writes normal script with
diminished need for effortful attentional supervision. The results
showed inefficient speech-manual performance and mirror script
writing in the left (nondominant) hand until around age 9 in normal
speakers and through age 16 in stutterers.

Specific results from the current study that support these
theories will now be addressed. Results of the handwriting
organization comparison suggest that stutterers compared to
nonstutterers did more poorly with their nondominant left hand during
the bimanual replication task and the task requiring increased
allocation of attention to the right hand. No differences in

97

organization occurred between stutterers and nonstutterers during
concurrent speech and bimanual handwriting. However, during
increased allocation of attention to the left hand, stutterers'
right hand organization was poorer than nonstutterers. Such results
tend to corraborate contentions that inefficient interhemispheric
integration is characteristic of disfluent speech.

Mirror image reversals. Across bimanual handwriting tasks,
stutterers had more left hand mirror reversals of digits and
letters than nonstutterers. The youngest group of normal speakers
had a high frequency of left hand mirror writing so that the
stutterers and nonstutterers in this age group (age 6 to 8.11 years)
did not differ in nondominant left hand mirror writing. During
bimanual writing with increased attention allocation to the left
hand, stutterers across age groups also had more mirror reversals
with the right hand than did nonstutterers. Although increased
allocation of attention to the left hand in older nonstutterers
(age 9 to 15) was not disruptive, it did produce disorganization
and mirror writing in the right hand of six- to nine—year-old
nonstutterers. Increased allocation of attention to the left hand,
during bimanual writing, increases attentional demands on the right
hemisphere, thereby increasing right hemisphere activity. This right
hemisphere activity then must be inhibited by the left hemisphere in
order for coordinated speech and manual activity to occur.
Difficulty in interhemispheric processing and hemispheric integration

arises if the corpus callosum is functionally immature and if
98

the left hemisphere cannot establish and maintain motor output
control. Interhemispheric processing difficulties in normal
speaking boys are related to delayed maturation of connecting
neural circuitry until age 9. Interhemispheric processing
difficulties in boys diagnosed as stutterers are more likely related
to the right hemisphere processing of speech and language. The
right hemisphere becomes language-involved through lack of left
hemisphere motor output control and associated lack of inhibition
of right hemisphere activity.

Previous research (Fitzgerald et al., 1984; Greiner et al.,
1985b) suggests that adult right-handed and left-handed stutterers
have poorer nondominant hand performance than nonstutterers when
writing digits and letters bimanually. These studies with adult
stutterers did not find differences in dominant hand performance,
which suggests that in right-handers, left hemisphere motor lead
control was intact. These studies with adults did, however, find
inhibitory deficiency in stutterers since right hemisphere activity
was not suppressed. Conversely, the results from the current study
suggest that right-handed childhood stutterers have poorer dominant
right hand performance than normal speaking children. The poorer
dominant hand performance was most consistent in the younger
stutterers (age 6 to 9) suggesting that this group of stutterers is
most deficient in left hemisphere motor lead necessary for control of

coordinated motor activity during lateralized performance.

99

Concurrent Unimanual Sequential Tappipg

The current findings support Greiner et al, 1985a, who also
found that concurrent speech and unimanual sequencing produce greater
speech and manual interference in stutterers than nonstutterers.
Moreover, spontaneous speech produced more disfluency for stutterers
than nonstutterers, and more disfluency than other speech tasks
(Greiner et al, 1985a).

Some researchers attribute interference effects to an imbalance
between the activation and inhibition of speech and motor control
systems of the left hemisphere, implying that the difficulty in
concurrent unimanual tasks arises from intrahemispheric competition.
However, in the Greiner et al (1985a) study, as in the current study,
interference also occurred in the left hand of right—handed subjects,
which suggests that right hemisphere activity is involved. This
interhemispheric processing has been related to the left hemisphere's
inability to inhibit the function of right hemisphere motor activity.
The results of the Greiner et al (1985a) study suggest that
regulation of speech and nonspeech motor control systems is
influenced more by interhemispheric integration processes than by
intrahemispheric competition. When system overload occurs, as it
does during the concurrent unimanual sequencing tasks, one
hemisphere's role in normal interhemispheric control processes may
become impaired. For right—handed stutterers, these problems seem to
be related to difficulties in the temporal regulation of the right

hemisphere, which interfere with the balance between the right and

100

left hemisphere activation and inhibition.

Manual interference. Right- and left-hand performance in
sequencing errors were greater in stutterers than nonstutterers
during concurrent unimanual sequencing, supporting the
interhemispheric processing theory. Compared to nonstutterers,
stutterers had fewer correct tapping sequences and significantly

higher tapping error rates. Tapping errors actually increased

with age in stutterers and decreased with age in nonstutterers.

Examination of the results of the concurrent task for
developmental trends suggests improvement in speech and nonspeech
manual skills with increasing age in normal speaking children and a
decline in performance with increasing age in stuttering children.
There are relatively few developmental investigations on time-sharing
(Wickens & Benel, 1982), but what evidence does exist indicates
that time-sharing ability increases with age (Birch, 1971;
Lipps—Birch, 1976; Hiscock & Kinsbourne, 1978; 0'Leary, 1980).
The current study indicates that concurrent unimanual sequencing
rates and correct tapping sequences increase with age and tapping
errors decrease with age in normal speaking children. Thus it would
seem that normal speaking children between the ages of 12 and 15
years have maximum capability for rapid and correct unimanual
sequencing compared to younger children, with improvement in tapping
rate and accuracy occurring between ages 6 and 15. Although
stutterers and nonstutterers do not differ in speed of sequential
tapping, accuracy of the sequential tapping is poorer for stutterers.

101

Given that across all subjects, the right hand had more rapid and
accurate sequential tapping than the left hand, and that stutterers
had as rapid a rate as nonstutterers but fewer correct tapping
sequences, it appears that errors in right hand sequencing might
have produced the significantly lower correct sequencing in
stutterers. This supports a superior left hemisphere ability for
manual sequencing in normal speaking right-handed children and a left
hemisphere role in the disruption of sequencing ability found in
stutterers.

Speech and manual tasks have been shown to be influenced by
hemispheric specialization. Spontaneous speech, requiring generative
and spontaneous temporal regulation and formulation of thought, has
been seen as a left hemisphere specialized task in right—handed
normal speaking males. Rhythmic speech and tone feedback were used
in the current study because of the structure they bring as
exogeneous sources of temporal regulation to the concurrent speech
and tapping task. Although there was an increase in the rate of
tapping and in the number of correct sequences while tapping with
auditory feedback for each finger tapped, throughout the experiment
the auditory feedback tasks also produced the most tapping errors.
The rhythmic speech task actually slowed the rate of tapping and was
also associated with the fewest tapping errors. Thus, the imposed
exogeneous temporal control of the rhythmic speech task improved
accuracy of unimanual sequencing over time, whereas the imposed

rhythm of the nonspeech auditory feedback task interfered with

102

sequencing accuracy over time. One strategy for optimizing
performance in the concurrent task would be to slow the rate of
manual activity, speech, or both, in an effort to gain maximum
control of one of the component processes or to allow sufficient
time for integration of speech and motor movements (Helm—Estabrooks,
1983). Rhythmic speech slows the rate of manual activity and speech
optimizing performance, whereas auditory feedback speeds performance
thereby decreasing accuracy of motor movements.

Speech interference. Spontaneous speech produced the most
interference on speech organization and more speech interference in
stutterers than nonstutterers as measured by disfluency. During all
the concurrent speech tasks, stutterers were more disfluent than
nonstutterers. Relevant to the component approach to differentiating
normal from pathological disfluency, concurrent speech produced more
within-word fragmentation in stutterers than in nonstutterers.
Stutterers were more disfluent than nonstutterers on five of the ten
disfluency—during-tapping criterion, that is, childhood stutterers
compared to nonstutterers have more airflow breaks, audible
prolongations, vowel substitutions, tense surges, and part-word
repetitions. In contrast, childhood stutterers and nonstutterers
did not differ in whole-word repetitions, phrase repetitions,
interjections, revisions or disrhythmic phonations. These later
criteria have been suggested as indicators of normal disfluency in
children (Adams, 1982). Disrhythmic phonations as a disfluency
variable produced no significant effects, supporting previous

research finding no differences between childhood stutterers and

103

nonstutterers in phonatory behavior (Schmitt & Cooper, 1978).
Speech organization skills appear to improve with age; older
children had more fluent speech than younger children particularly
during spontaneous speech. In addition, phrase repetitions that
are considered to be part of normal developmental disfluency were
less frequent in older children. These concurrent task results
support the Tingley and Allen (1975) findings that speech and manual
motor timing control improve with age. In addition, the results of
the current study support the suggestion that stutterers as a group
have less accurate speech and manual motor timing than do
nonstutterers (Cooper & Allen, 1977). It is important to emphasize,
however, that the subjects in Cooper and Allen's study were adults.
These findings do warrant the attention of researchers and clinicians
interested in identifying those stutterers who have basic motor
timing control deficits so as to modify or define specific
individualized therapy. Cooper and Allen (1977) suggest that adult
stutterers who completed and were released from therapy are more
accurate timers than are stutterers still in therapy. Perhaps
current successful stuttering therapies are those that assist the
stutterer in regaining control of motor timing.

A finding that is relevant to the nature of the speech task and
underlying hemispheric specialization is that spontaneous generative
speech, which has high temporal organization and regulation
requirements, produced more disfluencies than rhythmic speech.

Specifically, spontaneous speech produced more audible

104

prolongations, tense surges, part-word repetitions, whole-word
repetitions, phrase repetitions, interjections, and revisions.
Spontaneous generative speech was more disruptive than rhythmic
speech across 70% of the disfluency types for stutterers and
nonstutterers. It is important to note that during concurrent
speech and tapping, stutterers were more disfluent than
nonstutterers during all speech tasks. However, during pretest
nonconcurrent speech tasks the youngest and oldest age groups of
stutterers and nonstutterers did not differ in rhythmic speech
fluency. The rhythmic speech task assists fluency during a
nonconcurrent speech task by providing exogeneous temporal pacing
and slowing the rate of speech. Further evidence for this
comes from the concurrent speech tasks, during which stutterers had
more tense surges or phonatory tension during spontaneous than
during rhythmic speech. In contrast, nonstutterers had more tense
surges or phonatory tension during rhythmic than during spontaneous
speech. Perhaps the rhythmic speech task imposes exogeneous
speech timing control, assisting fluency in stutterers and
interfering with speech fluency in nonstutterers by competing with
internal pacing mechanisms (Wade, 1982).

One might speculate further that during spontaneous speech, the
left hemisphere provides temporal regulation of speech in
nonstutterers. In stutterers, this left hemisphere internal pacing
mechanism may be easily disrupted. This speculation is supported

by the part-word repetition findings. Stutterers had significantly

105

more part-word repetitions during spontaneous speech compared to
rhythmic speech. Nonstutterers had significantly more part-word
repetitions during rhythmic speech compared to spontaneous speech.

For normal disfluency variables (i.e., whole-word
repetitions, phrase repetitions, interjections, and revisions) more
disfluency occurred during spontaneous than during rhythmic speech
for all subjects. Thus the possibility exists that normal disfluency
and stuttering are regulated by different mechanisms with respect to
interhemispheric processes.

Normal disfluency is susceptible , however, to the influence of
lateral manual specialization as apparent in the Hand-Used-For—
Tapping interactions. Specifically, stutterers had more part-word
repetitions and whole-word repetitions while sequentially tapping
with the left hand as compared to the right hand. This suggests
an overload of the motor programming and temporal sequencing systems
when the right hemisphere is activated for motor sequencing, a
process which could be related to right hemisphere inefficiency for
motor sequencing or to inefficient interhemispheric communication.

For nonstutterers, results of speech fluency during tapping
indicate that normal speaking children were more disfluent while
tapping with the right hand compared to the left hand. Nonstutterers
had more part-word repetitions, whole—word repetitions, and phrase
repetitions when tapping with the right hand rather than the left
hand. The exception to this occurred in the youngest group of

children, who did not show differences in performance between hands

106

in the occurrence of phrase repetitions.

It is apparent, then, that in normal speaking children results
of time—sharing tasks involving speech and unimanual sequencing
support the view that in right-handers the left hemisphere is the
active hemisphere in temporal sequencing and regulation, whereas in
childhood stutterers the right hemisphere is more active thereby
producing inefficient temporal sequencing and regulation.
Interpersonal and Emotional Stress

Emotional stress questionnaire total score. The results
support previous reports (Greiner et 31" 1985) that stutterers
have higher levels of interpersonal stress than nonstutterers.
Greiner et a1 (1985) found that adult stutterers have higher levels
of social sensitivity and social isolation, and lower levels of
social confidence as measured by the Revised Willoughby Personality
Schedule. Greiner et al (1985) suggest that some stutterers do not
exhibit interpersonal stress, and in addition, there may be some
stutterers for whom anxiety is not a contributing factor in their
disfluency. Individual stutterers might, however, be affected by

word—specific anxiety, speech-situation anxiety, or general anxiety.

 

Questionnaire dimensions and factor analysis. The results
suggest that childhood stutterers generally have higher
interpersonal and emotional stress than nonstutterers. Factor

analysis revealed three dimensions in the questionnaire; social
confidence and self esteem, social and audience sensitivity, and
sociability or social interest. Stutterers of all ages show

107

lower social confidence and self esteem. The questionnaire item
which best exemplifies the confidence factor is, "Do you feel
that you are as good as the other children in your class?".
Childhood stutterers are more likely than normal speaking children to
think of themselves as a failure.

In responding to the items measuring social and audience
sensitivity, the youngest and oldest age groups of stutterers had the
highest levels of audience sensitivity. This dimension seems to be
related to speech—situation anxiety and is exemplified by one of
the subjects who repeatedly and anxiously asked the experimenter if
he was being audiotaped. The questionnaire items that most reliably
measure this dimension are related to speaking in front of class.
Giving a speech or talking in front of class is a speech situation
involving a peer group audience and thereby combines the related
emotions of speech-situation anxiety and social sensitivity.
Social and audience sensitivity are seen as similar emotions with
audience sensitivity being more specific to the immediate or imagined
presence of an audience.

The audience sensitivity scores remained relatively consistent
across ages for the nonstutterers. For stutterers, there was a
decrease in audience sensitivity in the 9 to 12 year old group.
Perhaps the stutterers in this preadolescent age group can negotiate
with peers and thereby diminish the fear of audience reaction.
However, when stutterers reach adolescence, the imaginary audience

and audience sensitivity emotions of normal adolescent development

108

combine with the actual negative social and peer reactions to the
stuttering behavior. This produces an increase in audience
sensitivity and is certainly a source of the emotional and
interpersonal stress seen in the adolescent stutterer.

In the area of sociability and social interest, the older age
groups (age 9 to 16 years) of stutterers had lower
sociability and social interest scores than the nonstutterers.
The questionnaire items that best exemplify this dimension relate
to "liking to meet" or "being around other children". The

sociability and social interest scores remained consistent for all

age groups of stutterers. The youngest group of nonstutterers
had significantly lower sociability scores than the older
nonstutterers. Young normal speaking children age 6 to 9 have not

had as much experience as older children in use of social skills and
therefore are more likely to have lower social ability and interest
scores than older normal speaking children. Childhood stutterers
between the ages of 6 and 16 continue to have negative experiences
with socialization and peers, thereby producing the lack of increase
in social interest and social ability that is seen in normal speaking
boys. A most feared speech situation for adult as well as childhood
stutterers, is the task of introducing oneself and saying one's own
name. This situation combines audience fear and sensitivity with
speech-situation anxiety so that simultaneous negative emotions are
experienced with the social skill and ability required when meeting

new people and making that first impression.

109

The predicted difference in emotional stress between older and
younger stutterers was not confirmed. This prediction arose from
studies like that of Beech and Fransella (1968), indicating that the
development of stuttering usually passes through stages from simple
repetition of sounds and words, through exacerbation of prolongations
and stuttering blocks, and then to the development of disturbances of
motor activity, leading ultimately in some individuals to
avoidance activities, emotional disturbances, and other forms of
social and psychological disruption.

Early childhood stutterers do not differ from older childhood
stutterers in social confidence and self esteem, audience
sensitivity, or social ability and social interest. Stutterers
between 6 and 16 years of age have higher levels of emotional stress
and specifically lower confidence and self esteem than nonstutterers.
Young normal speaking children age 6 to 9 have not had as much
experience as older children in use of social skills and therefore
are more likely to have lower social ability and interest scores than
older normal speaking children.

Results from the emotional stress questionnaire (ESQ) indicate
that this questionnaire is useful for assessment of dimensions of
emotional stress. The usefulness of the ESQ for children who
stutter is the therapeutic process that can be developed from the
personalized statements made in response to the questionnaire.
Perhaps a wide range of speech and communication disabled children

might also relate personalized statements in response to the

110

questionnaire items. Validification and test-retest reliability
studies of the ESQ with childhood stutterers should be done with
further analysis of dimensions of emotonal stress in other speech and
communication disabled children as well as normal speaking children
with other social, psychological, or psychiatric disturbance.

Strong negative emotions and high emotional stress exist in
childhood stutterers between age 6 and 16. Stuttering is
associated with inefficient right hemisphere regulation of speech.
Interestingly enough, Campbell (1982) has linked negative emotion to
the right hemisphere as well. If the emotional component and the
speech regulation component of stuttering are concurrently
controlled by the same hemisphere, system overload may cause
disruption in temporal regulation which eventually interfers with the
balance between right and left hemisphere activation and inhibition.

The theory that seems to best fit the data from the current
study is that normal developmentally disfluent children can be
differentiated from stutterers on the basis of lateralized
performance. The current study supports previous research
suggesting that some stutterers have poorer speech and nonspeech
manual timing control than do nonstutterers (Cooper & Allen, 1977).
It also supports the theory that some stutterers have timing control
deficits arising specifically when the right hemisphere is
responsible for temporal sequencing. Not only is the right
hemisphere inefficient for motor sequencing in right—handed males,
it overloads in stutterers who experience negative emotions

lll

directly associated with the temporal disruption in motor sequencing.

Future research needs to assess how directly negative emotions
and emotional stress impinge on motor programming in stutterers.
Future research also needs to assess right and left hemispheric
activity during a multiple concurrent task consisting of generative
thought, peripheral execution of speech and nonspeech motor
sequencing, and activation of negative emotions and stress.
Johnson et a1 (1959) suggest that stuttering is a perceptual and
evaluative problem that arises because of listener reaction to the
childhood disfluencies. It is certainly true that disfluency is
usually a transient disorder and that disruption in communication
between speaker and listener exacerbates the disorder. Dyadic
communication and conversational speech, in addition to possibly
being generative, involves listener reaction to stuttering blocks as
they occur. The more severe the stuttering and the more disruption
in sequencing that occurs for a stutterer, the more likely it will
be that a listener will have to react and be sensitive. The current
study demonstrates the additional component in this cycle of
communication; that is, the speaker's reaction to his or her own
stuttering and to the listener's reaction. The results of the
current study suggest that children between 6 and 15 years of age
are experiencing lowered self esteem and social confidence
because they stutter. The audience sensitivity arises through
fear of audience reaction to the stuttering. The stutterer's
reaction to his or her own stuttering is to not want to meet or be

112

around new children; again, to avoid confronting the emotional
stress associated with being a "stutterer".

A major limitation of the current study is that it did not
assess the direct relationship between negative emotions and
disruption in temporal sequencing of speech and manual performance,
so that the relationship exists in theory. What is apparent is that
stutterers have lateralized performance deficits during time sharing
tasks, and in addition, have higher levels of emotional stress when
compared to nonstutterers. Possible confounding effects in the
current study arise from the fact that this was an in-home study.
This tends to produce less control of social and environmental
influences during the actual experiment than would a laboratory
setting. The social influences might relate to negative emotions
associated with home. The home setting might not provoke audience
sensitivity as would an experimental laboratory setting.

Other possible confounding effects are harder to control. For
example, individual reaction to the stimulus picture cards vary in
type and intensity based on the child's experience. Since these
picture cards were used to elicit spontaneous speech that produced
the most disruption for stutterers, it is important to control these
stimuli differently, for example with verbal cues. For the
therapist, these individual reactions are probably personal
statements of emotions surrounding the picture, so that control

beyond that which occurred during the study may not be desired.

113

APPENDICES

114

APPENDIX A

Project Description Letter
Research Informed Consent Form

Individual Information Form

115

 

 

MICHIGAN STATE UNIVERSITY

 

DEVELOPMENTAL PSYCHOBIOLOGY LABORATORY
Speech Development Project

Department of Psychology

Psychology Research Building

East Lansing, Michigan 48824—1117

PROJECT DESCRIPTION LETTER

Investigators in the Developmental Psychobiology Laboratory at
Michigan State University are conducting a study of the relationship
between behavioral and emotional aspects of stuttering.

As a participant, you will complete a questionnaire concerning your
feelings about speaking situations, your reactions to various
experiences, and your degree of speech fluency. The final part of
this experiment will assess handedness and manual motor coordination
during speech. What this means is that we will ask you to talk aloud
while tapping with your fingers in sequence.

This letter is to inquire whether I may give Your name to these
investigators so that they or a member of their staff may contact you
to discuss your participation in their study. I would like to add
that in no way can any individual be identified once the information
is collected. Strict confidence and anonymity are guaranteed by
removing all names and identifying materials from any records that
are kept. I also would like to emphasize that this research does not
involve therapeutic intervention. This is basic research effort
which may prove useful for therapists and researchers and may have
implications for therapy.

Should you agree to consider participating in this work, I will
forward your name to the project staff. What will happen next is
that they will contact you and arrange an interview to discuss study
participation in greater detail. The research project will require
one 60—minute session and will be conducted in your home.

116

If you want to consider participating in this work, please sign the
attached form. Signing this form does not obligate you ip;§py_ g§y_
should ypu decide not £2_participate. Also, although I hope that you
will decide otherwise, please indicate on the attached form if you do
not wish to be contacted.

Finally, if you have any questions about this letter you may discuss
the project by calling me at 353—6468 or 353-3933.

Jay R. Greiner
Project Coordinator

Hiram E. Fitzgerald Lauren J. Harris
Professor Professor
Department of Psychology Department of Psychology

Paul A. Cooke
Assistant Professor
Department of Audiology and Speech Sciences

 

Please check one of the following:

Yes, I give my permission to release my name and phone
number so that the above named investigators may contact
me to provide more detail about their experiments.

No, I do not want to have my name released nor do I wish to
participate in the project described on the enclosure.

 

 

Signature Name: please print

 

 

Date Phone number

Please return this form in the self—addressed, stamped envelope.
Thank you.

117

MICHIGAN STATE UNIVERSITY

 

DEVELOPMENTAL PSYCHOBIOLOGY LABORATORY
Speech Development Project

Department of Psychology

Psychology Research Building

East Lansing, Michigan 48824—1117

RESEARCH CONSENT FORM

I have freely consented to take part in a scientific study being
conducted by Jay Greiner (Research Assistant), Hiram E. Fitzgerald
and Lauren J. Harris (Psychology), and Paul A. Cooke (Audiology and
Speech Sciences) all of Michigan State University.

The study has been explained to me and I understand the eXplanation
that has been given and what my participation will involve.

I understand that the results of the study will be treated in strict
confidence and that I will remain anonymous. Within these
restrictions I understand that general results may be presented at
professional and scientific meetings and may appear in appropriate
professional journals and other publications. Moreover, copies of
research reports will be made available to me at my request.

I understand that my participation in the study does not guarantee
any beneficial results to me directly.

Finally, I understand that, at my request, I can receive additional
explanation of the study after my participation is completed and that
I will not receive any financial compensation for participation in
this one—hour study.

Signed:

 

Parental Signature:

 

Date:

 

NOTE: This form is to be held in locked file.

118

MICHIGAN STATE UNIVERSITY

 

DEVELOPMENTAL PSYCHOBIOLOGY LABORATORY
Speech Development Project

Department of Psychology

Psychology Research Building

East Lansing, Michigan 48824-1117

INDIVIDUAL INFORMATION

This information is to be kept in the locked file folder and used to

l) assign code numbers, and 2) provide research summaries to
participants.

Participant:

Name: Phone Number:

 

Address:

 

 

 

I would like to receive summaries of the research results when they
are available.

Yes NO

 

Code Number

119

APPENDIX B

Bimanual Handwriting Stimuli
Digits From 1 through 12

Letters From A through L

120

789Wflfl

1.2.3.456

APPENDIX C

Emotional
Stress

Questionnaire

123

10.

11.

12.

13.

14.

EMOTIONAL STRESS QUESTIONNAIRE

Do you ever think that something you do may be made

fun of by other children?

Do you ever worry about doing something dumb?

,Do you ever think of yourself as different from other

children?

Do you ever worry about how you look?

Do you ever worry about what other children think of
you?

Do you like to talk in front of class?

Do you like to get up in front of class and give a
speech?

Do you ever feel lonely when you are with other
children?

Do you ever feel lonely when you are with your
friends?

If an important person (teacher, principal) came up to
talk to you, would you want to talk to him/her?

Do you like to meet new children?

Do you like to play with other children?

When a new student comes to your school, do you go up
and talk to him?

Do you like to be around other children?

124

15.

16.

17.

18.

19.
20.
21.
22.
23.

24.

25.

26.

27.

28.

29.

30.

Do you like to be around other people?

If your teacher says your work is not good, do you
feel bad?

If you are having trouble putting a puzzle together,
do you keep trying even if none of your friends could
do it?

If the teacher asks a question in class (in front of
class) and you know the answer, do you raise your hand
to answer the question?

Do you think that your classmates are better than you?
Do you feel bad when you lose?

I get scared when I must speak in front of class.

I like to talk to other children at recess.

I like when we have to work in small groups at school.
I feel good when the teacher calls on someone else
other than me in class.

I like writing better than answering outloud in class.
I like to read outloud in class.

I like to go to birthday parties and meet new

children.

Do you feel that you are as good as the other children

in your class?

Do you think you have many good things about you?

Do you think of yourself as a failure?

125

31.

32.

33.

34.

Do you often think that you can do things better

other children?
Do you think of yourself as lucky?
Do you think you are a good person?

Do you ever wish you could be someone else?

126

than

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