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English Pages 148 [161] Year 1967
THE MODIFICATION OF
STUTTERING
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EUGENE
DONALD
J.
J.
BRUTTEN
SHOEMAKER
Southern Illinois University
PRENTICE-HALL, INC.,
Englewood Cliffs, New Jersey
KLINCK EMOR Al Concordia
Teacher~
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tlBRAR~ Collegf
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London
PRENTICE-HALL INTERNATIONAL, INC., PRENTICE-HALL OF AUSTRALIA, PTY. LTD.,
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Toronto PRENTICE-HALL OF INDIA PRIVATE LTD., New Delhi PRENTICE-HALL OF JAPAN, INC., Tokyo PRENTICE-RALL OF CANADA, LTD.,
The Modification of Stuttering, by Eugene J. Brutten and Donald J. Shoemaker
© 1967 by Prentice-Hall, Inc., Englewood Cliffs, N.]. All rights reserved. No part of this book may be reproduced in any form or by any means without permission in \vriting from the publisher.
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FOREWORD
After years of wandering in the jungle of stuttering theory and research it is with great relief and appreciation that one finds a clearing, with cultivated fields, pathways precisely outlined, and boundaries clearly marked. This book is such a clearing. It does not profess to have laid the whole forest bare. Tl1ickets and swamps still remain for other men to master, but in the area of learning theory as it applies to the problem of stuttering the auLhors have done deeds that leave us all indebted. The accomplishment is all the more noteworthy because the present state of behavioral science as it applies to learning and unlearning in general still leaves much to be desired. The model presented here, like all models, will doubtless find revisions in future years. That is what models are for. They help free us from the inertia bred of confusion; they permit us Lo progress. Jn the tangle of information that surrounds stuttering they are indispensable if we are to understand the disorder. Yet in this book there is still more. In it the reader will discover for himself implications for research and therapy that are most exciting. CHARLES VAN RIPER
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PREFACE
Most speech pathologists agree that learning is basically involved in the development and maintenance of stuttering. There is considerable disagreement, however, concerning how best to concep· tualize the learning process and how to structure treatment based on learning principles. Until recently most speech pathologists were concerned with the integration of data within a particular learning or behavior theory. In most cases, the theorists were specific about the learning process but did not develop specific therapy procedures based on learning theory. Consequently, altl1ough there have been lively discussions about the role of learning in the development and maintenance of stuttering, therapy has been largely unaffected by these discussions or by the experimental data on the modification and extinction of behavior. This book is intended to acquaint both the college student and the professional speecl1 pathologist with the learning theories around which current thinking about stuttering has been structured, with the data important to the fundamental predictions of these theories, and with a two-process theory of learning that seems promising for both the theoretical integration of the data on stuttering and the therapeutic modification of it. This book is designed, then, for the student of stuttering who wants a data-bound approach to learning theory and therapy. ••
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PREFACE
A su.mmary of current learning-theory approaches to stuttering in the first part of the text serves as background for the discussion of a two-process learning theory. In che theoretical discussion, the onset, development, and maintenance of stuttering are described in terms of the p.r inciples derived from the experiments of learning and of stuttering. The data we inspect indicate that learning plays a central role in the development of stuttering. We then turn to the experimental work on learning to determine which behavior model or learning theory best fits the known data. Although no theoretical posture seems flawless, we conclude that a two-process learning theory provides not only the most adequate explanation of behavior in general but also the most meaningful approach to stuttering. One particular value of this theory is that it incorporates both emotional and instrumental responding. As a result, when the theorist applies the two-process approach to behavior l1e takes into account both the involuntary negative emotion (anxiety, tension, fear, stress, etc.) that appears to be consistently associated with stuttering and the voluntary adjustments that the stutterer often learns as a mea11s of avoiding or escaping the noxious consequences of stuttering. The second part of the book examines the implications of the two-process theory for the modification of stuttering. This examination is based on the experimental literature on laboratory procedures for the extinction of learned emotional and instrumental responses. In exploring the literature it becomes evident that while there are still tnany unresolved issues concerning the most efficient way to achieve behavior change, interest seems to converge on certain procedures and on a growing body of experimental data indicating that these procedures produce significant changes. The clinical procedures for the modificatio11 of stuttering are based as closely as possible on the techniques that have produced behavior change in the laboratory. We reason, in other words, that it is possible to abstract certain essential characteristics from the laboratory procedures and to use them as the basis for developing a program for treating stt1ttering. This task was made incalculably easier because of tl1e pioneering work of a small group of psychologists and speech pathologists wl10 have been developing learning-based approaches to tl1erapy for behavior disorders since the 1950's. We
PREFACE
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were able to lean heavily on the efforts and experiences of these behavior theorists and therapists, and we are particularly indebted to 0. Hobart Mowrer and Joseph Wolpe. Although the two-process therapy described in this book is based on the logic of current learning theory and the extinction procedures developed in the laboratory, the resulting approach to behavior therapy was tested, modified, and honed by daily experience with stutterers in the Southern Illinois University Clinical Center and the Marion Memorial Hospital Speech and Hearing Center. We have been able, in this way, to check informally on whether specific laboratory procedures can be modified for use in the clinic and whether they are effective. This evaluation has been going on for the last three years, and it is now apparent that the use of laboratory procedures in the clinic is limited most often only by the therapist's imagination. Moreover, it has been our clinical experience that two-process therapy has produced more positive behavior change for a larger percentage of clients in less time than any methodology we have previously employed. This should not be taken as an indication that this therapy has been universally effective; some of the stutterers have indeed sl1own dramatic improvement"' but others have improved only slightly. The important fact, however, is that most of the stutterers we have seen have improved markedly. This informal evaluation is an outgrowth of the continued modification of therapeutic procedures during their development and the full expectation that further changes as well as additions will be forthcoming. The therapist should not be bot1nd, therefore, by the procedures that are described. Behavior therapy is in its infancy, and its application to the modification of stuttering will be se~ved by those therapists who advance our knowledge in the efficient means of achieving extinction. A book such as this is obviously the product of innumerable in· .fluences. The authors are indebted to their teachers and to those speech pathologists and psychologists who came before them and whose work influenced their choice of theoretical concepts and therapet1tic procedures. We are also deeply indebted to our many students who l1ave shared with us the development of the ideas and the clinical methods that have been presented. Their ideas, questions, criticisms, and encouragement markedly influenced our
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PREFACE
own thinking. In addition, their willingness to function as clinicianexperimenters significantly expanded our opportunity to test various clinical procedures. The authors are most grateful to Dr. Herbert Koepp-Baker for those efforts that led to the initiation of this book and whose help led to its completion; to Dr. Robert West, who read an early version of the book and encouraged us to expand and elaborate our ideas; to Mr. Alden Hall, whose support of our work in the Clinical Center added immeasurably to the final product; and to Dr. Isaac P. Brackett and Dr. David Ehrenfreund, the chairmen of our respective departments, who, like the entire administration of Southern Illinois University, encouraged us constantly. In addition we are grateful to Mr. Robert Hawkins and Mrs. Fran O'Brecht for typing the manuscript's outline, to Miss Mary Latta for typing what must have seemed like innumerable drafts of the manuscript, and to Mr. Lawrence M. Webster for his valuable assistance in many phases of the book's production. The authors are particularly grateful to their wives and children for their patience and for their constant support and encouragement. It is to them that this book is truly dedicated.
E. J. B. D. J. S.
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CONTENTS
CHAPTER I
BERAVIORISTIC APPROACHES TO STUTTERING
3
Concepts Underlying Traditional Theories of Stuttering, 4 Concepts Underlying Learning Theory Approaches to Stuttering, 6 Conclusion, 16 Bibliography, 17 CHAPTER II
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR Emotional Learning, The Development of Stuttering, Instrumental Learning, Fluency, Fluency Failure, and Stuttering, Bibliography,
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27 31 35 39 43
CHAPTER III
PREDISPOSING FACTORS Bibliography, 57 •
XI
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CONTENTS
CHAPTER IV
A THEORY FOR THE MODIFICATION OF STUTTERING
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Extinction of Classically Conditioned R esponses, 62 Extinction of Instrumental R esponses, 65 Bibliography, 83
CHAPTER V
CLINICAL PROCEDURES FOR THE MODIFICATION OF STUTTERING
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Determining Critical Stimuli, 92 The Individual Interview, 93 The Group Interview, 101 Determining Critical Stimuli in the Child, 102 Control of R esponse Strength Through Stimulus Generalization, I 07 Methods of Controlled Stimulus Presentation, 110 Inhibition of Negative Emotional R esponses, 118 Inhibition of Instrumental R esponses, 126 Determining Instrumental Responses, 131 The Ordering of Instrumental Responses for Extinction, 135 The Strategy of Two-Process Theory, 137 Bibliograpl1y, 138
INDEX 141
THE ,
MODIFICATION OF STUTTERING
CHAPTER
BEHAVIORISTIC APPROACHES TO STlTIVl'ERING
Stuttering of e\·en moderate severity is clearly obvious and highly disturbing, both to the stutterer and the listener. As a result, speech pathologists, physicians, psychologists, and concerned nonprofessionals have been intensely interested in stuttering and its treatment for many years. This interest has produced a multitude of ideas, theories, and i)rocedures, but only a limited amount of hard data. Basically, howe,•er, altl1ough the specific theoretical approaches to stuttering have differed, one underlying viewpoint has appeared consistently throughout the years. The theoretician has generally taken the position that the repetitions, prolongations, hesitations, posturings, and other such behaviors usually described as stuttering are the observable manifestations of an as yet unobservable disorder in the physiological, neurological, or psychological f unctioning of the organism. This conclusion 11as been based, in part, upon the fact that thorough examination of the organs, muscles, and neural structures involved in the speech of stutterers typically fails to uncover any consistent malformation or malfunction. Furthermore, examination also usually reveals that the stutterer can adequately produce all the necessary speech sounds, both in isolation and in complex speech. Stuttering usually occurs when the individual is trying to integrate 3
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these sot1nds to form complex, meaningful speech. Stuttering is tl1erefore usually thought of as a disorder not of the speech-producing organs then1selves but of the processes that integrate the activities of these organs. To complicate the matter even further, stuttering does not alzuays occur even during attempts to produce integrated speech. What was said fluently today may be stuttered tomorrow. A word or sound tl1at was stuttered this morning may cause no difficulty this afternoon. Although certain sounds or words seem to give more trouble than others, the situation in which one is trying to speak also appears to be of importance. Talking to one's child on Monday may go smoothly, but asking an employer for a raise on Wednesday may lead to a debacle of hesitations, repetitions, finger snappings, and other bizarre behaviors. Singing a song with a group around a camp fire may be pure delight, bt1t making a reservation for a flight to Chicago may lead to a cataclysmic breakdown of communication. In other words, even the consistency of malfunction found in most disorders is missing. With one leg shorter than the other, the individual knows he is going to limp. Even the phobic individual knows he will be afraid when the elevator door is closed. Bt1t with stuttering, even though patterns undoubtedly exist, they are more like cycles or complex waveforms than simple one-to-one relationships. Obviously, the sources of this difficulty are complex interactions of an t1nknown number of vaguely known factors. Concepts Underlying Traditional Theories of Stuttering Many different theoretical structures have been put foTth to encompass these observations. The theories l1ave differed primarily in the inferences or 11ypotheses made about the nature of these causal factors. One group of theorists, for example, has relied heavily on physical or neurological concepts. This group has been concerned with measuring phenomena such as integration of neural firing, diadochokinesis, deviations of bloocl chemistry, and possibly inheritecl disorders of pl1ysiological or neurological processes. A second group of theorists has relied primarily on psychological concepts. This group has been interested in pl1enomena such as the stutterer's personality development, the emotional climate of the childl1ood home, guilt reactions and psychological conflict, and
BEHAVIORISTIC APPROACHES TO STUTTERING
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the reactions of other peo1)le to the child's speech. A third group of theorists has tried to combine these pl1ysiogenic and psychogenic approacl1es. lYiembers of this i11teractionist group have generally hypothesized that a physiological or neurological weakness leads to a breakdown in speech production when the individual experiences fear or tension. Although physiogenic and psychogenic theorists agree that the observable bel1avior of stuttering results from underlying catlses, they differ radically in regard to how tl1ese causes sl1ould be interpreted and how they should be treated. Most of the physiogenic theorists 11a,1e postulated the existence of lesions, diseases, or other malfunctions or malfom1ations as the basis of stt1ttering. Tl1ey see the stutterer as a passive recipient, through genetic 1)rocess, congenital disorder, disease, or trauma, of a malfunction that interferes with the production of normal speech. Altl1ough they recognize that the stutterer may have a psychological reaction to the physical disorder and that this reaction may i11directly increase the severity of the problem, these theorists feel that the disorder itself should be attacked in the same way as other medically defined disorders. On the other hand, most psychogenically oriented theorists have postulated that the stutterer is not physically different from the nonstutterer. They hypothesize, instead, that he is different in his personality structure or functioning. Most of these theorists have been directly or indirectly influenced by the psychoanalytic, psychodynamic approach to personality development and functioning. Generally, these theorists take tl1e position that the stutterer, as a result of his unique life experience, has developed personality conflicts or weaknesses which in some way interfere with normal speaking. Most of these theorists believe that the stutterer has consistently experienced speech-associated punishment to the point that he tries to inhibit the act of speaking, and by so doing interrupts and distorts the normal flow of speech. Thus, these theorists see the stutte1·er as attempting to meet the demands of a situation by speaking but at the same time trying to protect himself by not speaking. He reacts neurotically or is caught in a conflict for which disordered speech is the primary symptom. In addition, the disttorted speech leads to negative reactions from listeners, which in turn makes the individual more defensive, and a vicious cycle is established that leads to progressive deterioration.
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BEHAVlORISTIC APPROACHES TO STU'l"IERING
A critical difference between these points of view is the psychogenic theorists' conte11tion that the stutterer's interpersonal experience has been most important in developing the conditions leading to the disorder. The stutterer is thought to have a speech problem because he has developed attitudes, motives, or needs in regard to speecl1 situations or the act of speaking which interfere with speech. These particular attitudes, motives, or needs have developed because of the way significant adults, particularly parents, have interacted, and continue to interact, with the stutterer. As in the physiogenic point of view, the stutterer is still the recipie11t of an unfortunate set of circumstances. In the psychogenic approach, however, the basic disorder is psychological rather than constitutional, and the development of the disorder is primarily dependent upon interpersonal rather than impersonal processes. Similarly, in the psychogenic approach the changes occurring in the organism are seen as being a function of how experience changes the individual's personality rather than 11ow it damages his physical or neurological processes. At a very ge11eral level, the theoretical proposal that personality change is a result of experience and not primarily a result of maturation or direct organic alteration, may be taken to mean that the change has resulted from learning. In this sense, the psychogenic theorists have implied that learning is involved in the development of stuttering. In tl1ese approaches, however, the description of "learning" has usually been vague and inexact. The stress has been on the development of personality dynamics and the effect of these dynamics on speech rather than on tl1e learning of specific responses or on the nature of the learning process itself. Thus, while the psychodynamic approaches have, by implication, involved learning, they have not utilized t11e concepts of psychological learning theory as this area is ust1ally de6.11ed.
Concepts Underlying Learning Theory Approaches to Stuttering In modern psychological learning theory, the basic concepts are quite different from tl1ose of most personality theories. Personality theorists discuss behavior in terms of 11ighly abstract concepts, sucl1 as personality types, traits, or generalized motive patterns; learning theorists discuss behavior in terms of less abstract units, such as
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reponses or response chains. Also, personality theorists see behavior primarily as a result of personality characteristics; learning theorists see behavior as a result of relationships that have developed between environmental or internal stimuli and responses. Although obviously an oversimplification, it might be said that the learning theorist divides the psychological world into stimuli, responses, and the relationships between these two classes of phenomena that develop from experience. The relationships include habit strength, stimulus generalization, response extinction, and response-contingent reinforcemenL To add further complexity, stimuli may be proprioceptive or exteroceptive; responses may be emotional or instrumental; and reinforcements may be positive or negative. Of most importance, perhaps, is that these concepts do not imply such a thing as a type of person. The emphasis is on behaviors, their antecedents and consequences, and not on the classification of people into character types. When stuttering is approached from this point of view, then, the problem is not one of analyzing the personality type or types that produce stuttering, but one of determining the conditions of learning that produce stuttering behavior. The learning theorist does not see the stutterer as one member of a class of individuals whose stuttering is symi;tomatic of a personality disorder shared by all members of the class, but as someone who has learned to respond in a given way to certain stimulus conditions. With the exception, perhaps, of certain constitutional similarities and similarities in learning experiences, there is no reason to expect more similarity among people who stutter than among those who have learned to shoot golf in the low 70's or to play ping-pong exceptionally well. It is not that the individuals are similar in terms of such global personality concepts as types or traits, but that the behaviors learned in relation to specific stimulus conditions are similar. In recent years, many people have tried to apply the concepts and methods of learning theory to various clinical problems and behaviors. Although Shoben (10) considered psychotherapy a problem in response extinction as early as 1949, and Dollard and Miller (2) attempted a learning theory reconstruction of psychoanalytically oriented therapy in 1950, the present surge of interest is probably more closely related to the p11blication of Wolpe's (17) work in 1958 and to the interest aroused by experiments in verbal condition-
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BEHAVIORISTIC APPROACHES TO STU'rI"ERING
ing (1, 3, 11). Although those tryir1g to develop learning oriented therapy differ in theory and method there is basic agreement that abnormal behaviors are best thought of as learned responses and best treated by response modification or response extinction. In other words, learning theory has shifted away from the idea that individuals are neurotic or have neuroses toward the idea that they have learned maladaptive stimulus-response relationships. The relationships can be maladaptive either because they cause the organism to expend energy needlessly or because they make it impossible for the organism to achieve reinforcements which would otherwise be available to it. It is important to note in this connection that from the point of view of learning theory, there is no basic difference in tl1e way maladaptive and adaptive behaviors are learned. The same learning principles apply to both. For those who approach treatment within a learning frame of reference, the therapist is like an experimenter trying to develop the conditions most conducive to respo11se extinction or response change. From this point of view, of course, it is most important to know the conditions under which learning is being maintained, the nature of the reinforcement scl1edules uncler which the organism has been operating, th.e reactive inhibition that may be produced by the responses i11 question, the possibility that competing responses may be brought into the extinction situatio11, etc. Although the literature on response change in laboratory situations is far from complete or definitive, the studies provide many gt1ideposts for tl1ose trying to develop testable analogues for changing behavior in clinical situations. The learning theorist takes the position that the extinction or change of maladaptive behaviors, like their acquisitio11, is not basically different from that of other behaviors. This position allows considerable freedom of movement between the learning laboratory and the treatment clinic. For a nt1mber of years, experimental data have led researchers to conclude that stuttering l1as, at least in part, the properties of learned bel1avior. Since the late 1940's several systematic attempts have been macle to inte.g rate these data within the framework of behavior theory. The n1ost notable theoretical attempts in this direction have bee11 made by Wischner and by Sheehan, who discuss learning in drive reduction terms, and by Shames a11d Sherrick, who
BEHAVlORISTlC APPROACHES TO STUTTERING
9
define learning within an operant framework.* Wischner, and Shames and Sherrick, take the position that stuttering is basically an avoidance behavior; Sheehan considers stuttering a symptom of a double approach-avoidance conflict.
Wischner Wischner hypothesizes that the presence of learned anxiety is fundamental to the onset of stuttering. This motive force of anxiety, or anxiety drive, ca11 result from the punishment of any behavioral pattern that is in the person's response repertoire, but the development is most clearly understandable if the punishment is associated with speech activity. If, for example, a child's normal disfluent speech is met with punishment from adults, there is a high probability that speech-associated anxiety will develop. Bnder s11ch conditions, the adults' noxious reactions to the disfluencies lead to "painful" responses in the child. If these conditions are repeated often enough, speech under certain circumstances becomes a response-produced cue for eliciting anxiety in the child, and tliis state d1ives the child to avoid the noxious stimulation. According to Wischner, anxiety may, through symptom choice, lead to the development and perpetuation of behavior other than stuttering. Anxiety, however, may lead to stuttering if it serves as a drive to avoid the painful stimulation that is associated with normal disfluency. This drive to avoid the noxiousness of adult disapproval might result in the absence of all language were it not for the fact that the drive to communicate is in conflict with it. This conflict between the desire to speak and the fear of speaking generates random speech behavior. The particular random speech responses that are learned are those that lead most consistently and successfully to the avoidance of punishment. This is, of course, reinforcing. But this reinforcement of anxiety reduction leads further to the learning of speech responses that are not only different from the normal disfluent behavior but may also result in a generally faulty use of the speech organs. The learning of these different-fromnormal avoidant speech responses signifies the existence of stuttering behavior. • The positions attribuled to each of these theoreticians are based on the references found at the end of this chapter.
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BEHAVlORISTIC APPROACHES TO STUTTERING
As the stuttering develops further, originally neutral stimuli that occurred around the same time as the disapproval of disfiuency become, by virtue of this association, conditioned indicators of danger. These conditioned stimuli function adaptively to elicit anxiety in the anticipation of the forthcoming noxious stimulation. The anxiety drive then motivates behavior directed toward avoiding the noxious stimulation. Wischner holds that there are two types of anxiety-evoking stimuli found among stutterers. These two types are general situational anxiety, which is elicited by essentially nonverbal stimuli, and specific word anxiety, which is elicited by verbal stimuli. These anxiety-evoking stimuli will differ among stutterers because of the individual differences in the situational and word environments that are associated with noxious stimttlation. The symptom cluster that is stuttering behavior also varies from individual to individual because stutterers employ different behaviors to overcome the anticipated speech difficulty. Those behaviors which are instrumental in avoiding the expected punishment are reinforced by a reduction in the anxiety drive and become an integral part of the stuttering pattern. In other words, the reinforcement of different instrumental devices creates symptom variations among stutterers. Furthermore, a particular individual's pattern of symptoms will change from time to time as the presence or absence of reinforcement changes. Consistent with his Hullian orientation, Wischner describes stuttering as a nonintegrative behavior that is maintained by some type of reinforcement. It is hypothesized that this maintaining reinforcement may result from (a) the reduction in tension when a feared word is completed, (b) the 1·eduction in anxiety when a feared word or speech situation is avoided, (c) the confirmation that occurs when expected speech difficulty is followed by stuttering, and (d) the secondary gains or benefits that result fro1n being a stutterer. Such reinforcements may perpetuate stuttering even though its consequences are more punishing than rewarding. The maladaptive or nonintegrative learning occurs because the reinforcement precedes the penalties. Wischner also states that the perpetuation 0£ stuttering behavior may be discussed in terms of its resistance to extinction. Reinforcement is fundamental to this resistance. Extinction is even more difficult if tl1is reinforcement is based on the successful avoidance of
BERAVIORISTIC APPROACHES TO STUTTERING
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noxious stin1ulation. In this circt1mstance, the absence of noxious stimulation (t1nconditioned stimulus) leads to increased response strength rather than extinction. Extinction would occur only if the stutterer exhibited the originally disapproved behavior, presumably disflt1ent speech responses, and found that the punishing consequences no longer occurred. Wischner's theorizing is thus a relatively straightforward application of Hullian learning principles to the phenomenon of stuttering. Through speech-associated punishment, fear is learned in relation to situatio11al and word stimuli. This learned fear, in conjunction with the individual's desire to communicate, leads to a conflict and, in tu1·n, to changes in speech patterns. Those patterns that are associated with the reinforcement of fear reduction come to serve as avoidance behaviors and achieve the status of habits. Their maintenance and their change depend on the reinforcement regime to which the individual is subjected.
Sheehan Sheehan, although he utilizes certain Hullian principles, also includes various psychoanalytic concepts in his theorizing. In considering the onset of stuttering, Sheehan maintains that when an individual experiences guilt, he also experiences conflicting needs to be silent and not to be silent. The approach-avoidance conflict created by these opposing needs leads to oscillations and fixations in behavior which at the speech level are the repetitions and prolongations so noticeable in stuttering. Sheehan thus considers stuttering the symptomatic expression of the turmoil of the inner self as it struggles with conflicting impulses. Various classes of symptoms may result from a state of conflict. In stuttering, the basic reactions of conflict are expressed through speech and take the specific form of rhythm breaks or interruptions in the forward flow of speech. But the reasons why the conflict is ex1)ressed through speech and why the specific symptom choice is stuttering are unknown and await discovery through research. In time, emotionality over the existent stuttering behavior becomes a basic element of the conflict that produces stuttering. At that point, stuttering involves the conflicting drives toward speaking and not speaking, as well as toward remaining silent and not remaining silent. In this double approach-avoidance conflict the
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BEHAVIORISTIC .APPROACHES TO STUTIERING
attempt to speak results in stuttering and consequent shame. Silence, on tl1e other ha11d, signals tl1e abandonment of speech communication, and this creates frustration. Guilt becomes attached to both choices, and stuttering is the resulting compromise between speech and silence. Sheehan maintains that the conftict between approach drives (to speak and to remain silent) and the avoidance motivation (to not speak and not to remain silent) arises at five distinct levels. Thus, conflict may result from the need to speak and the avoidance of (a) words and their phonetic elements which through past conditioning have become indicators or cues of a noxious state. (b) situations tliat provoke fear because of previously punishing experiences, (c) spoken expressions that have threatening emotional content, (d) relationships with individuals in a position of authority. and (e) ego-testing circumstances which threaten either failure or success. Sheehan utilizes the concept of secondary guilt to refer to the emotional feelings tl1at the stutterer experiences because he is aware that stuttering is both distressing and a source of conflict for the listener. The secondary symptoms of stuttering are indicative of the speaker's individualized manner of dealing with stressful circumstances. These compensatory activities characterize secondary stuttering and are the predominant behaviors noticed by the listener. These symptoms of conflict may result from the attempt to overcome the avoidance motive, to prevent the o.c currence of stuttering behavior, or to cope with the stress of existing stuttering. The secondary symptoms that are habitually employed . . . are not merely chance products of random instrumental learning l)ut necessarily reflect the dynamics of the stutterer and the pattern of interpersonal relations from wl1ich they e1nerged. The stutterer's pattern is not a superficial symptom but a significant and revealing part of the stutterer's personality [8, pp.· 129-30].
The secondary symptoms may increase secondary guilt because of the counterfeit characteristics and attitudes the stutterer t1ses to achieve fluency. The guilt arising from this dishonesty becomes conditioned to both the individual characteristics that are foreign to the self and the resultant speech fluency. Since stuttering is the result of conflict, its termination depends
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on the resolution of a conflict moment. The conflict can be resolved either by increasing the approach drive for speaking until it exceeds the avoidance drive or by reducing the fear-based avoidance until it no longer interferes with the approach drive. Sheehan maintains that it is most likely that the conflict is resolved because the occurrence of stuttering reduces the fear-motivated avoidance. This reduction in the fear takes place duri11g the stuttering moment and may result because (a) the bel1avior that was being avoided has already occurred and cannot be 11idden, (b) the proprioceptive feedback from the speech behavior reduces the 11elpless feeling that is inhere11t in the unknown, or (c) the forces of aggressio11 have been spent by the occurrence of this speech act. In any event, fear reduction occurs when abnormality has been displayed and the fear is "satisfied." In discussing the conditions that maintain stuttering, Sheeha11 hypothesizes that the reduction in the avoidance drive leads 11ltimately to the resolution of a speech-associated conftict. In the process, however, fear increases beca11se the reduction in drive brings the speake1- closer to the avoided goal. This fear decreases after the goal has been reached and the st11ttered word completed. This terminal drive reduction reinforces and perpetuates those behaviors that were instrumental in tl1e completion of the stuttered word. Stutte1ing may also be perpetLtated as the result of sensory learning. That is, the auditory, proprioceptive, and visual stimuli associated with the act of stuttering may be important in both producing and modifying it. Sheehan1 like Wischner, makes clear-cut use of drive theory concepts, but Sheehan places more emphasis on the conce1Jt of motivational conflict. Also, Sheehan integrates certain concepts from psychoanalytic theory with those of drive theory. Although Sheehan assumes that the central basis for stuttering is the behavioral fluctuations that occur in an approach-avoidance conflict situation, he also assumes that both the cause and intensification of the conflict lie in g11ilt feelings, and he sees the particular behavioral pattern that develops more as a psychodynamically construed defense system than as a set of responses reinforced by drive reduction. Above all, however, Sl1eehan depends so heavily on the concept of approach-avoidance conflict and its behavioral effects that his theory can justifiably be called a conflict theory of stuttering.
14
BEHAVIORISTIC APPROACHES TO STUTTERING
Shames and Sherrick Shames and Sherrick discuss stuttering within the Skinnerian learning framework. In this system an operant behavior is one that affects the respo11ding organism's external environment. Disfluency is tl1us considered an operant behavior with a high frequency of unreinforced emission among children. Disftuency shows varied behavioral forms such as repetition, hesitation, and prolongation. Shames and Sherrick indicate that the circumstances associated with the original occurrence of disfiuent behaviors are not yet known. They hypothesize that repetitive disfiuencies may be telated to the babbling emitted by infants during the early period of speech development. They also think it possible that disfluencies result fTom the physiological limitations of an organism in which the organs used for speech have a more primary or determinative biologic function. In contrast to these biologic l1ypotheses Shames and Sherrick also consider the possibility that repetition, the most common form of disflt1ency, may be (a) the result of tl1e speaker's trying to increase his intelligibility, (b) related to a child's need to speak under deprivational or punishing conditions, (c) a way of avoiding or postponing the punishing consequences of a verbal response, (d) the result of a child's early u-aining in tl1e amenities of conversation that the listener must ren1air1 silent until the partner has fi11ished speaking, or (e) the speaker's attempt to hold the listener's attention while he composes and edits his speech so as to ptevent the silence that would cause tl1e listener to start speaking. Disfluent behaviors 1nay be shaped by factors independent of those that led to their initial appearance. An ·o perant bel1avior, such as disfiuency, is by definition a response that is modified by the environmental consequences of its appearance. If the response that these environmental consequences follow increases in frequency, then the consequences are, by definition, positive reinforcers. Removing these positively reinforcing stimuli leads to response decrement and extinction. If the response is followed by punishing stimuli, it will be interrupted or depressed. If tl1ese punishing stimt1li are also aversive, those responses that reduce or remove them will occur more frequently. Negative reinforcement
BEHAVIORISTIC APPROACHES TO STUTTERING
15
is defined by the increased freq11ency of those responses which result in the reduction or removal of aversive stimuli. Disfluency ancl stuttering are similar and possibly continuous response forms rather than separate behavioral classes. Indeed, the circumstances that lead to the conditioning of disfluency may be etiologically related to those associated with the development of stuttering. For example, parents to '\Vhom disfluencies are aversive would probably find stuttering aversive too. These parents might punish their child, contingent upon 11is disfluent or stuttering behavior. They wot1ld continue to use punishment if it temporarily depresses the responses that they consider noxious and, as a result, their use of it is reinforced. The disfluencies emitted by children are not usually reinforced differentially by the listeners in the environment, and therefore the response rate does not change. Instead the child's general verbal behavior is positively reinforced. On the otl1er hand, if disfluent responses are punished by a listener he becomes, by this act, a conditioned aversive stimulus. He would then signify the threat of punishment and generate emotionality. An aversive listener causes silence and/or struggle behaviors that are different from the usual disfl.uent response forms. These changed response forms are the stutterings the child emits to terminate the listener's aversive reactions and avoid the punishment that was a consequence of the original disfiuency. In discussing the further development and maintenance of stuttering, Shames and Sherrick assert that the repetitions, silences, and prolongations that are the child's adjustive responses may be negatively reinforced or p'L1nished by the aversive listening environment. Response change co11tinues until a dynamic equilibrium is reached in which the positive reinforcement of a response exceeds either the aversive stimulation that occasions behavior change or the reinforcement for change. Response contingent punishment and reinforcement modify disfiuen t behaviors, and the result is a degenerate response form. These atypical and bizarre verbal behaviors may also be aversive to the speaker himself, so that the response continually changes in order to terminate the punished speech form. Tl1e reinforcing consequences, however, are not critically specific either to t11e disfluent
16
BEHAVIORISTIC APPROACHES TO STU'l"I'ERING
behavior or the adjustive responses. Therefore, any other behaviors which happen to be emitted when verbal responses receive reinforcement will also increase in frequency. These secondary behaviors are not directly related to speech and so may involve any part of tl1e body. A stutterer's particular speech patterns depend on response contingent reinforcement. Thus, if the listening environment elicits a changed form of speech and this change brings reinforcement from the environment, this behavior will occur more often. Stuttering can be maintained by negative as well as positive reinforcement. Negative reinforcement may result from the stutterer rationalizing or defending his inadequate behavior by shifting the responsibility for it from himself to l1is stuttering responses or to tl1e behavioral consequences that emanate from his environment. Shames and Sherrick stress the point that "there is no single, sitnple contingency for stuttering." The development of stuttering depends on positive and negative reinforcements. These :response contingent consequences are on schedL1les of reinforcement that are as yet unknown, although one would expect them to be complex and multiple. Shames and Sl1errick also point out that the behavioral sequence they suggest is only one of many possible models describing the onset and development of stuttering. This particular model arises from and is consistent with the lite1·ature on stuttering found in the field of speech pathology. The cogency of tllls or any other model will depend on further experimentation and o bserva ti on. Conclusjon
There are, then, several different explanatory approaches to stuttering witllln the general framework of psychological learning theory. These clifferences are representative of those found within the field of behavior theory jtself. For example, the central aspect of Sheehan's theoretical position is the approach-avoidance conflict and its behavioral implications. He also integrates this construct with psychodynamically derived concepts. Wischner, on the other hand, has remained within a Hullian drive theory framework. He considers stuttering as behavior iliat is learned and maintained on the basis of drive redtiction. Finally, Sl1ames and Sherrick in ilie operant
BEHAVIORISTIC APPROACHES TO STUTTERING
17
tradition, avoiding some of the problems inherent in the acceptance of drive reduction as a basic theoretical construct, have considered stuttering as behavior that is contingently controlled by environmental events of a reinforcing or aversi,,e nature. As a grot1p, ho\ve·ver, learning theories are distinct from either the somatic or psychodynamic approaches. The fundamental agreement among these learning theories is that stuttering develops as a resttlt of experience and is responsive to changes in experience as are other learned behaviors. They also agree that the treatment of stuttering should be a process of changing behavior through the directed or controlled unlearning of already established patterns and the relearning of new patterns.
Bibliography 1. Cohen, B. D., H. I. Kalish, J. R. Thurston, and E. Cohen, "Experimental manipulation of verbal behavior,"]. exper. Psychol., 47:106-10, 1954. 2. Dollard, J., and N. ?>.filler, Personality and Psychotherapy, fVfcGrawHill, Ne\v York, 1950. 3. Greenspoon, J ., "The reinforcing effect of two spoken sounds on the &equency of two responses," Amer. ]. Psychol., 68:409-16, 1955. 4. Sl1arnes G., and C. Sherrick, "A discussion of non-fluency and stuttering as operant behavior," ].S.H.D., 28:3-18, 1963. 5. Sheehan, J. G., "Tl1e modification of stuttering through no11-reinforcement," ]. Ab. Soc. Psychol., 46:51-63,· 1951. 6. , "Theory and treatment of stuttering as an approacl1-avoidance conflict," ]. Psychol., 36:24-47, 1953. 7. , "An integration of psychotherapy and speecl1 therapy tl1rough a conflict tl1eory of stuttering," ].S.H.D., 19:474-82, 19!/4. 8. , "Conflict theory of stuttering," in J. Eisenson (ed.), Stuttering: A Symposium, Harper, New York, 1958. 9. , P. A. Cortese, and R. G. Harley, "Guilt, shame, and grapl1ic projections of stuttering," ].S.H.D., 27:129-39, 1962. 10. Shoben, E. J., Jr., "Psychotherapy as a problem in learning theory," Psycho/. Bull., 46:366-92, 1949. 11. Verplanck, W. S., "The control of the content of conversation: Reinforcement of statements of opinion," ). Ab. Soc. Psychol., 51 :668-76, 1955. 12. Wischner, G. ]., "Stuttering behavior and learning: A program of research," Ph.D. Diss., Univ. of Iowa, 1947.
18 13. 14. 15. 16.
17.
BEHAVIORISTIC APPROACHES TO STUITERING
, "An experimental approach to stuttering as learned behavior," American Psychol., 3:278-79, 1948. , "Stuttering behavior and learning: A preliminary theoretical formulation," ].S.H.D., 15:324-35, 1950. , "An experimental approach to expectancy and anxiety in stuttering behavior," ].S.H.D., 17: 139-54, 1952. , "Anxiety-reduction as reinforcement in maladaptive behavior: Evidence in stutterers' representations of the moment of difficulty," ]. Ab. Soc. Psychol., 47:566-71, 1952. Wolpe, J., Psycliotherapy by Reciprocal Inhibition, Stanford Univ. Press, Stanford, J958.
CHAPTER
STU
ERING:
CONDITIONED DISINTEGRATION
OF SPEECH BEHAVIOR
Though Wischner's frame of reference is Hullian, and Shames and Sherrick's is Skinnerian, both theoreticians indicate that stuttering is a learned modification of speech behavior that results from the noxious or aversive responses of the environment to disfluencies. Sheehan, in a different theoretical vein, employs the conflict construct found in the learning theory of Dollard and Miller (21). He proposes that stuttering is the result of response conflicts that are expressed through speech. There is thus essential agreement among these theorists that stuttering is most accurately construed as a behavioral response. They also agree that the acquisition of stuttering behavior is not a unique process; stuttering is acquireu in accordance with the same learning principles as other responses. These theorists believe, therefore, that the learning and maintenance of stuttering depend on some form of reinforcement. According to Wischner the most probable source of reinforcement is the reduction of anxiety or tension that comes at the end of the stuttering response. Sheehan holds a similar position, but has also stated that in some cases the reinforcement is not the reduction in fear but possibly the drive-inducing circumstance of frustration (56). This interpretation is based on Sheehan's experimental findings that although a majority of a sample of stutterers showed a 21
22
STU1"1"ERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
reduction in drive at the end of a stuttering moment, as measured by a projective method, others indicated the presence of drive induction. Shames and Sherrick also view the stimulus-response chain in terms of reinforcement, but as we have seen, their theoretical position does not require one to explain the process of reinforcement; reinforcement is defined by the increased rate of response performance. Although the reinforcement conc~pt is quite helpful in organizing some of the data regarding stuttering, its use poses a major theoretical problem. This problem arises because in several welldesigned studies and in many clinical reports, stuttering was not influenced by punishment in a manner that would be predicted by the law of effect, one of the fundamental laws of learning. According to this basic principle of behavior, responses that are followed by reward will be learned and maintained, and responses that are followed by punishment will be suppressed or extinguished. This point of view indicates that stuttering should decrease if followed by punishment and increase if followed by reward. The experience of many speech therapists, however, and the research of many speech pathologists is directly opposite to what the law of effect would predict. Many speech therapists report that if stuttering is punished, it increases rather than decreases (31, 4, 55). Furthermore, the results of several research investigations showed that the frequency of stuttering does not typically decrease and may indeed increase as a function of noxious stimulation. This relationship became apparent in the first experimental investigation of the effect of punishment on the frequency of stuttering. In this study Van Riper (69) fastened electrodes to the experimental subjects and then asked them to read aloud the same passage three consecutive times. Prior to the fourth oral reading, a sample shock was delivered, and the stutterers were told that at the completion of that trial they would be shocked for each spasm that had occurred. This specific spasm-associated threat produced increased fluency failure in 15 of the 16 subjects, and an average increment of 5.2 stutterings. When, in contrast, the stutterers were told that they would be shocked at the end of the reading, but that the number of shocks would not depend on the number of spasms, there was an average increase of only 1.5 stutterings and one-third of the subjects showed
STU1"l'ERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
23
no increase at all. On the basis of this statistically significant difference, Van Riper concluded that it was the punishment for stuttering and not the shock itself that accounted for most of the increase in fluency failure. The apparent conclusiveness of these findings may have been responsible for the lack of interest in further investigations of the effect of noxious stimulation on stuttering. The next experimental attack on this antecedent-consequent relationship did not occur until fifteen years later. In this investigation Frick (26) explored the effect on stuttering of shocks that (a) depended on the number of stutterings in an oral reading and were delivered at the completion of the reading, as in Van Riper's study; (b) were response contingent, that is, were delivered immediately after each stuttered word; and (c) were contingent upon each word, whether it was stuttered or not. A comparison between these three shock conditions revealed no significant differences. Shock that was contingent upon stuttering produced no less fluency failure than did shock that was delivered at the termination of the entire oral reading or shock that was contingent upon the completion of each spoken word whether stuttered or not. The shock conditions were then combined, and the frequency of stuttering was compared to that found in a fourth, nonshock, condition. The stutterers were found to have significantly more fluency failure under the combined shock condition than under the nonshock condition. It may well have been these experimental findings and the clinical reports that led both Wischner and $heehan to use the MowrerUllman hypothesis to explain the maintenance of stuttering in the face of punishing consequences. According to Mowrer and Ullmai1 (46), if all things are equal, a response will be reinforced ot exti,nguished depending on whether the rewarding or punishing consequences, respectively, follow the cessation of the behavior more closely in time. In keeping with this hypothesis, Wischner (80) and Sheehan (55) have maintained that a stuttering moment is maladaptively reinforced by the emotional drive reduction associated with its completion and that this reinforcement occurs before punishment. Drive reduction is thus assumed to follow each occurrence of stuttering. This assumption would then imply that the occurrence of stuttering leads to an increased probability of future stuttering. Indeed, an increment in stuttering would be most likely if speech were repeatedly elicited with both the stimulus words and
24
STU'l"IERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
the stimulus environment held constant. In contrast to this anticipation, however, there is a wealth of experimental data showing clearly that under such conditions the frequency of stuttering decreases or adapts (72, 32). Moreover., adaptation under these circumstances appears to be greater than when either the material (27, 51) or the speech environment (20) is changed. Wischner and Sheehan both deal with the critical challenge of these data by suggesting that adaptation is the result of nonreinforcement. This explanation represents a significant inconsistency since their previous use of maladaptive reinforcement precludes, by definition, their assumption of nonreinforcement (13, 7). In otl1er words, it does not appear appropriate to suggest, on the one hand, that stuttering is maintained because it is reinforced by drive reduction, and on the other hand, to say that stuttering adaptation is a function of nonreinforcement. Wischner and Sheehan are not, of course, the only theoreticians who find it difficult to deal with the clata on punishment. Though Shames and Sherrick did not discuss the data on punishment, the results of Van Riper and Frick, which indicate that stuttering does not decrease when punished, would also be alien to their theoretical framework. Within the Skinnerian frame of reference, reinforcement of an operant is descriptively defined in terms of response strength; positive reinforcers are those stimuli whose contingent presentation results in a measured increase in the response they follow, and negative reinforcers are those stimuli whose contingent occt1rrence leads to the acquisition of a changed manner of behaving. Moreover, negative reinforcement is said to have occurred when there is an increased probability of a response other than the one that was aversively stimulated. In this light, the maintenance of, or increment in, measured stt1ttering despite the punishment of electric shock might be taken to mean that such stimulation is not a noxious or aversive stimulus, is a positive reinforcer, or is an aversive stimulus but is exceeded by the maintaining presence of positive reinforcement. On the basis of the available experimental data it appears unlikely that shock is not an aversive stimulus or that it is a positive reinforcer. On the other hand, stuttering, at least according to Van Riper and Frick, was not affected by either the punishment of anticipated shock or by the noxiousness of response-contingent shock in a way that is typical of other responses.
STUTTERING: CONDffiONED DISINTEGRATION OF SPEECH BEHAVIOR
25
There exists, therefore, a conflict between theoretical expectations and data concerning the reactions of stuttering to punishment. Perhaps this paradox is the result of theoreticians having mistakenly assumed that stuttering is a learned instrumental response. The critical import of the clinical and experimental findings on tl1e effect of punishment on stuttering led learning theorists to a renewed and vigorous investigation of this entire problem. A recent series of studies bears importantly though indirectly on the question of whether punishment increases or decreases the frequency of stuttering. In each of these investigations electric shock was made contingent upon the fluency failures of nonstutterers. In the first investigation (57, 59), the data indicated that response-contin·g ent shock did not result in a statistically significant reduction of the speaker's fluency failures when compared with either his basal or extinction rate. A redesigned version of this investigation also indicated that response-contingent shock did not significantly decrease fluency failures when compared with the speaker's rate under nonshock conditions (58" 59). In each of these studies, an an.alysis of the effect of contingent punishment was also made by· comparing the mean nt1mber of fluency failures exhibited during the first half and the last hall of the shock condition. In the first study there was no significant decrease from the first half to the second half of the shock condition, but in the second study there was a significant decrease (5 per cent level of confidence) within the shock condition. In order to determine whether the latter decrease occurred because the shock was response-contingent or because the shock was a nonspecific depressant of dysfluent behavior, the experimenters next compared the effect of contingent and random sl1ock on the frequency of fluency failure (58, 59). In this experiment, unlike the two preceding studies, response-contingent punishment decreased the frequency of fluency failure when compared to a preshock period. However, the withdrawal of shock did not produce the increase in fluency failure that is typically found under such circumstances. Stevens (65), in a similar study, also compared the effect of response-contingent shock and the absence of differential reinforcement on the frequency of interjections of nonstutterers. These experimental conditions did not result in a significant difference in the number of interjections. Taken as a whole the results of the studies on the effect of response-contingent punishment of the fluency failures of nonstut-
26
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
terers, tI:iough not unequivocal, are consistent with the data indicating that punishment of shock does not reduce the fluency failures of stutterers.• A more current study by Martin, Brookshire, and Siegel (39), however, has indicated that the contingent punishment of an avoidance or "secondary" stuttering behavior will result in its suppression. The disparity between this remarkable result and the data of the previous studies is noteworthy. In the earlier research, punishment was made contingent upon the complex of behaviors defined as stuttering, whether "primary" or "secondary," rather than upon a specific aspect of the stuttering moment. In this investigation, however, the punishment of two selected segments of stuttering, nose-wrinkling and an interjection, led to their decrease. The discrepancy between the results of the more recent study and those already viewed may be due to basic differences in methodology (7). Specifically, the resulting differences in the effect of punishment suggest that the concept of the stuttering moment may be too molar and that fundamental differences in the behaviors encompassed by this term may have been masked. As a commentary on this supposition it is important to point out that though the use of responsecontingent shock in the Martin, Brookshire, and Siegel study suppressed certain avoidant or "secondary" responses of the stuttering moment, its continued use increased a "primary" aspect. That is, although contingent shock decreased both nose-wrinkling and the interjection, it also produced an eight-fold increase in the number of prolongations. Furthermore, this incFease was associated with a depression in the rate of verbal output, which made the increase in prolongations even more striking. Moreover, the increase in the number of prolongations was a persistent rather than a momentary occt1rrence. The contention that the stuttering moment is too molar a concept has not been supported by the data of a study recently published by Martin and Siegel (40). In this study, stuttering, whether defined
•These findings are in contrast to those o{ Flanagan, Goldiamond, and Azrin, who have reported that a response-contingent aversive stimulus, a 105-decibel tone, resulted in a marked decrease in fluency failures. However, we have chosen 11ot to discuss these findings because of methodological difficulties brought to our attention by one of the experimenters and because Biggs and Sheehan (3) were unable to substantiate these findings in an attempted replication of this study.
STUTI'ERING; CONDITIONED DI SINTEGRATION OF SPEECH BEHAVIOR
27
broadly in terms of the total moment or narrowly in terms of specific behaviors, was decreased through the use of contingent shock. The disparities among the results of these various studies make it evident that continued experimentation is needed to clarify the issue of whether or nor stuttering, as broadly or narrowly defined, is decreased by punishment as are other responses. At the present time, however, at least two major implications can be drawn from the studies of the effects of contingent shock on stuttering. First, these studies suggest that the complex of behaviors that have historically been labeled as stuttering is not unitary; rather, since some of the behaviors decrease in rate when followed by punishment while others increase, it appears justified to hypothesize that at least two distinct behavioral phenomena are involved in stuttering. Second, the tendency of certain parts of stuttering to increase with contingent punishment suggests the existence of a relationship between these parts and fear conditioning. This hypothesis appears justified because it has been clearly demonstrated that the response of fear, like the occurrence of fluency failure, is positively related to the intensity and frequency of punishment. Also, the tendency of other parts of stuttering to decrease with the occurrence of contingent punishment suggests that these parts are best construed as instrumental responses, that is, behaviors that are instrumental in obtaining reinforcements or avoiding noxious circumstances. Thus, stuttering appears to be a complex phenomenon, certain components of which are more closely related to behaviors such as fear, whereas others are more closely related to behaviors such as jumping across a barrier in a shuttle box or turning right or left in a T maze. A comprehensive theory of stuttering must encompass both of these aspects. It appears vital, therefore, that a two-process explanation be utilized. This explanation should account botl1 for behaviors that increase and those that decrease with contingent punishment. It is apparent that this dichotomous approach will also lead to a redefinition of stuttering.
Emotional Learning One theoretical approach to answerin·g the dilemma created by the data on punishment is not to assume that all learning is based
28
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
on response reinforcement. This is the position taken by a number of theorists (60, 41, 63, 44). Although specific aspects of the theoretical positions vary from theorist to theorist, one basic and consistent proposition is that emotional learning is based on stimulus contiguity, or classical conditioning, rather than on reinforcement that is temporally associated with the termination of a response. In such emotional learning the organism learns to experience a positive or negative emotional reaction to a previously neutral stimulus through the contiguous presentation of this stimulus with a stimulus that already, either on a learned or unlearned basis, leads to the emotional reaction.• In other words, the emotional value of a stimulus can be modified through the organism's experiencing that stimulus contiguously with stimuli that already lead to a given emotional reaction. In general, most theorists have felt that the strength of the conditioned emotional response depends on the intensity of the unconditioned stimulus. Wolpe (82), however, maintains that emotional learning may occur even when the unconditioned stimulus is of low intensity if it is frequently experienced. This position is supported by studies that indicate that mild shocks may produce experimental neurosis (38, I, 37) and by case history data that indicate that mild anxiety summates when repeatedly experienced (2). The effects of emotionality on behavior in general have been studied by numerous investigators. In regard to negative emotion, the findings indicate that a stimulus to which a person has learned to respond fearfully will produce behaviors quite similar to those produced by stimuli that are physically painful. In general, under conditions of both pain and fear, the organism engages in a series of adjustive behaviors until one of them effectively reduces the intensity of the stimulus to a tolerable level. If the intensity of the pain or fear is low, the flow of behavior is usually an orderly process: a succession of well-developed, well-integrated behavioral • Kimball has pointed out that although a two-process theory of the type we set forth was developed as an explanation of avoidance learning, it is now apparent that it may be extended to learning involving positive stimulation. More specifically, he indicates that "the theory which several investigators seem to be converging upon parallels tl1at for avoidance learning: A classically conditioned component stemming from an association between neutral stimuli and reward provides a motivational element (incentive), which motivates performance and also provides reward . . ." (35, p. 266).
STU"l~'ERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
29
patterns. If, ho,vever, the pain or fear is of high intensity, and if the first adjustive behaviors do not reduce the intensity of the stimulus, the orderliness of the behavioral pattern is disrupted; the behavioral segments occur very rapidly and are fragmented and overlapping. One segment may be initiated and then quickly inhibited before its completion. Another segment may be begun and then be similarly inhibited. Finally, some mixture of two or more segments may occur. Often, parts of competing behaviors occur in such a way that the only result is useless muscular oscillation or even muscular rigidity. In short, under such conditions behavior becomes disintegrated and is usually grossly ineffective. The disintegration of behavior we have described is clearly evident in a naive rat experiencing intense electric shock in a Skinner Box or in a human trapped in a burning theater. Under such conditions, the disintegration of speech behavior along with the disintegration of other instrumental behaviors would scarcely be surprising. It appears, however, that even with less intense fearproducing stimulus conditions, speech behavior often shows evidence of such disorganization. Actually, this, too, should be no surprise if we consider the high level of neuromuscular coordination required for the production of fluent speech. Under these conditions, while gross motor behavior may show little or no indication of disintegration, behavior patterns such as speech, which require fine coordination, may show considerable evidence of disruption. It should be little cause for wonder, then, that most communication theorists concerned with stuttering have been led by their observations to accept the importance of negative emotion (fear, anxiety, stress, etc.) as a basic antecedent to stuttering.• In this respect, the major question has not been whether a relationship exists between negative emotion and stuttering, but rather, what the nature of the relationship is. From our point of view, this paradigm of behavioral failure or disintegration created by negative emotion is fundamental to any discussion of that specific form of fluency failure termed stuttering. In this light, stuttering is not seen as an instrumental response that depends on reinforcement for acquisition or maintenance, but as it
Validation for this position rests, in part, on introspective reports (78, 56), be· havioral observations (68, 36, 20, 26), and physiological measures (24, 49, 25, 67, 68. 66, 12).
30
STU1I"IERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
a fluency failure caused by the cognitive and motoric disorganization associated with negative emotion. Whatever else may be involved in stuttering, the speaker is engaged in the performance of a motor act that requires fine coordination, and this performance is disrupted. The disorganization is seen as part of the generalized autonomic response complex which in essence defines ~egative emotion. While the exact pattern of this disruption is probably unlearned and somewhat idiosyncratic, the relationship between the eliciting stimuli and the emotionality that induces disrupted speech is learned. This learning to respond with negative emotion to stimuli takes place through classical conditioning. In essence, then, it is hypothesized that when an individual stutters, he is experiencing learned negative emotion (autonomic activity) which is disrupting to his normally fluent speech behavior. This position is supported by the research which has shown that noxious stimuli are capable of disrupting the speech behavior of nonstutterers and that the fluency failures that result from such stimulation are not distinguishable from the universal characteristics of stuttering. One of the important aspects of this model is that since it considers stuttering as behavioral disintegration rather than as acquired instrumental responses, it obviates the dilemma created by the data indicating that stuttering does not consistently act like a response under punishment conditions. In many studies, stuttering correlates positively rather than negatively with the frequency and intensity of noxio11s stimulation, and this fact has led us to the position that it is the disintegration of fluent speech. The classic investigation that was concerned with the effect of noxious stimuli on the speech behavior of nonstutterers was conducted by Hill (29). In this study an originally neutral stimulus (red light) was paired with an unconditioned stimulus (shock) during manual performance. By means of the conditioning that resulted from this pairing, the red light became a noxious stimulus that was similar to the shock in its effect. Following this conditioning, the red light was presented while the subjects spoke a, series of sentences that were different from each other and previously unseen by the subjects. As a consequence of this stimulus presentation, there occurred repetitive and prolonged vocal behaviors that Hill found to be indistinguishable from stuttering. These data were consistent with his position that one needs to ascertain the origin
STUTI'ERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
31
of repetitions and prolongations rather than to assume merely that such oral behaviors are normally emitted as a part of tl1e speaker's response repertoire. Savoye (50) also investigated the disruptive effect of noxious stimuli on the normally fluent speech of nonstutterers. She studied the frequency of fl11ency failures exhibited by normal speakers for a timed period before, during, and after the presentation of a conditioned stimulus that was consistently followed by an unconditioned stimulus of shock. The results of this investigation revealed that in each of these timed periods the experimental subjects showed significantly more disfluency than did the control group. Stassi's (64) recent investigation is also relevant to this discussion since it concerned the effect of prescheduled punishment and reward on the speech behavior of nonstutterers. The results of this study showed that significantly greater fluency failure occurred.under the punishing circumstances than under the reward conditions. In summary, it has been hypothesized that intense negative em~ tion which is not reduced by instrumental attempts to co·p e with a noxious stimulus field may lead to the disruption of normally fluent speech in a significant number of individuals. It has also been postulated that stuttering is that form of fluency failure which results from the classically conditioned or learned relationship between certain stimuli and negative emotion. Similarly, it is hypothesized that speech fluency is facilitated by positive emotional reactions. In this sense, positive emotion is not just the absence of negative emotion. Rather, it is a function of positive stimulation. Although most of the research on emotionality and stuttering has been concerned with negative emotional reactions, some data on the positive side have been collected. These data indicate that the positive anticipation of fluency is quite reliably associated with the occurrence of fluent speech behavior (34, 73) and that the removal of words on which stuttering is anticipated or has previously occurred will lead to markedly increased fluency (33, 34, 14).
The Development of Stuttering A behavioral continuum exists between fluency and fluency failure. In addition, since learning is a gradual process, it follows that any discrete analysis of the behavioral development from fluency
32
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
to that form of flue·ncy failure which has its base in conditioned negative emotion (stuttering) will, of necessity, result in some fundamental injury to the ongoing continuity of reality. Furthermore, it is obvious that any pedagogic description of the course of behavior development must be based on characteristics that are consistently found in the species rather than on those specific to a particular member of the species. Thus, the stages of development that will be described and their order of occurrence should be seen as representative of tendency rather than inviolable occurrences. Broadly speaking we differentiate between (a) speech that is predominantly fluent and in which the occasional fluency. failures are unlearned, (b) speech that tends to be predominantly fluent but marked by a relatively increased frequency and severity of fluency failure which is induced by classically conditioned negative emotion, and (c) speech that is further disorganized by the heightened emotionality that may become a consequence of fluency failure. Stage One speech behavior is common to most speakers. The stimulus field in which speech behavior is elicited is associated with a positive, or at least a relatively neutral, emotional environment. This emotional climate may be the result of previous experience with this or a similar stimulus field. The circumstance associated with fluency is illustrated in Figure 11-1. The occasional
$
~
emotional
•R
..........~-normally fluent speech
r1+,0)
--learned - - ·-unlearned
11-1: The instrumencal response of speech (R) is normally fluent in stimulus circumstances (S) that elicit positive (r +) or neutral (rJ emotion. FIGURE
fluenc::y failures that occur result from various organismically determined stress factors. One form of organismically disruptive stress is noxious stimulation of situational origin. But no matter what form the stress takes, the consequent fluency failures are not the result of learning. Furthermore, in those instances where the fluency failure is a function of negative emotion it is dependent upon current situational circumstances rather than upon learning, and as a
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
33
result, the speech disturbances are sporadic rather than consistent. This is illustrated in the following diagram (Figure II-2):
$
'
'~
emotional
•R ,,, ..,... ,,,..,
rc-l
~ £.. fluency failure
--learned - - - unlearned
IT-2, Stage 1: The instrumental response of speech (R) fails to maintain fluency in stimulus situations (S) that sporadically ""' elicit negative emotion (r _). The relationship is sporadic because it is not learned.
FIGURE
Stage Two is marked by the quantitative increase in, and qualitative modification of, fluency failures that are indicative of emotional conditioning which has developed from the contiguous • association of originally neutral stimuli with noxious (unconditioned) stimuli. This relationship between specific situational stimuli and negative emotion in essence defines tl1e onset of stuttering, since the fluency failure now depends on learning. As a consequence, stuttering behavior shows a consistency that makes it appear chained to eliciting stimulus situations. However, as characterized in Figure II-3, it is the negative emotional response and
$
~
emotional
•R
,.,,."'~stuttering
r(-)
--learned - - - unlearned
..
II-3, Stage 2: Stuttering (R) is the failure of fluent speech that results from stimulus situations (S) that chronically elicit negative emotion (r _).The relationship is consistent because it is learned.
FIGURE
not the stuttering which is conditioned to the evoking stimulus events. Each time, of course, that the individual reacts with emotionality to certain situational stimuli the possibility exists, through higher order conditioning, that additional stimuli in the situation may become conditioned stimuli which are capable of evoking negative emotional responses. It should be pointed out, also, that
34
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
a progressively greater number and range of stimuli become capable of eliciting a disruptive emotional response through stimulus generalization. In addition, the already established emotional conditioning is strengthened each time noxious stimulation reoccurs, and as a result the probability increases that these stimuli will elicit a negative emotional response. It is evident from this description that negative emotional conditioning and consequent fluency failure are progressive in nature. On the more positive side, in the usl1al course of events, positive emotional conditioni11g and fluency are also developing. Thus, as a function of experience there js a quantitative increase in both negative and positive emotional conditioning and their consequent effects. Nevertheless, when all else is equal, the emotional and fluency ratios remain relatively constant for a particular individual over time. Stage Three in the growth of stuttering is defined by the development of conditioned negative emotional reactions to the act of speaking, the words employed, or the speech produced. Generally, this speech-specific conditioning arises because stuttering is a noxious stimulus to the listener, and consequently, listeners often respond punitively to the stutterer. These punitive responses may take the form of derision, impatience, or a simple decrease in time spent interacting with the stutterer. In addition, the stutterer himself may perceive his speech as inadequate or unacceptable, and may experience negative emotion even though he receives little actual negative reaction from the environment. This latter circumstance is more likely to occur when stuttering begins well after the onset of speech development. Under such a condition, the individual has had a chance to develop a base rate of speech performance from which deviations in fluency become obvious. In this advanced stage of stuttering, of course, there may occur a summation of conditioned emotionality from general situational stimuli and from the stimuli associated with speech. This latter speech-associated emotionality may be conditioned to the presence of an important external listener and/or to certain aspects of the speaker's own behavior. Thus, even the response-produced cues of speaking may become conditioned to anxiety (70, 71). The emotional reactions to the general situation, to the external listener, to the internal listener, and to the proprioceptive stimuli produced
STUTIERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
35
by speaking may all combine to produce an increased probability of speech disruption. This set of circumstances is illustrated in Figure II-4.
•Rs
~
~
"-..
~
·R~xternal internal I
S
..,....,....1"W' stuttering • Y • Y emotional I (-}I - - - - - - - 1 (-)
lear'n~
2
- - - unlearned
11-4, Stage 3: Stuttering (f;8 ) leads to noxious responses from the external and internal listeners (R8 f:{)· The resulting negative emotion (r _) 2 summates with the negative emotion (r _) 1 elicited by the initial stimulus situation (S), and stuttering is increased. FIGURE
It should be realized that the very structure of speech will result in an i"ncreased association of certain speech and speech-associated stimuli with emotional conditioning. As such, a greater probability exists for certain cues to evoke an anxiety response than others. Thus, the fact that the various parts of speech show an ordered probability of being stuttered is explained by the fact that the frequency of usage of the various parts of speech is similarly ordered (10, 11). Indeed, the evidence points to the presence of a highly significant and nearly perfect rank correlation between the .Probability of stuttering on various parts of speech and their frequency of usage in the English language (81). If one carries this approach to its next logical step, then it can be seen that word anxiety may also become ·u nequally associated with components of the word units and result in increased emotionality about specific sounds and sound combinations.
Instrumental Learning A sequence of conditions has been described under which fluency failure that is the result of unlearned and sporadic noxious events gradually develops into a relatively consistent occurrence that depends on emotional conditioning. Within this framework stuttering is that class of fluency failure which is the consequence of classically conditioned negative emotion. It seems obvious that emotional learning does not account for
36
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
all behavioral acquisition. Thus, it is posited that learning involves two processes: • The first process, as we have seen, is learning to respond emotionally to stimuli as a result of classical conditioning. The basis of this learning is the stimulus substitution that resul ts from the contiguous presentation of conditioned and unconditioned stimuli. The second process has come to be known as instrumental learning. Learning of this kind occurs when a response is instrumental in reducing a negative drive or increasing a positive one. As a consequence of such reinforcement there is an increased probability of the behavior's occurrence when the evoking stimulus or a similar stimulus pattern is present. It is noteworthy, with respect to this behavioral dichotomy, that two-process theorists have often held that a significantly basic distinction exists between classical and instrumental responses. In general terms, classical conditioning is tho11ght to involve the autonomic nervous system, which mediates primarily involuntary, smooth muscle activity, whereas instrumental conditioning is thought to involve the central nervot1s system, which mediates primarily voluntary, striate muscle activity (42, 43, 62). These distinctions are usually made with an awareness that, although the evidence generally favors this dichotomy, a degree of overlapping exists in tl1ese processes. Nevertheless, these distinctions tend to be consonant with the division of learning into cla·ssical (emotional) and instrumental (adjustive) formats. The hypothesized interaction between classical and instrumental learning is valuable because it brings to the fore a number of important functional relationships that might otherwise escape consideration. For example, it is often contended that instrumental condi tio11ing appears to depend on the prior occurrence of classical learning. Moreover, accepting this hypothesis makes it meaningful to consider both negative and positive emotion as drive states wl1ose presence stimulates instrumental activity and whose decrease or increase, respectively, serves to reinforce instrumental responses (30, 45, 21, 52, 53, 48). Mowrer, as early as 1947, discussed antecedent-consequent relationship between classically conditioned • Kimball (35, p. 98), in his evaluation of the differences between classical and instrumental learning, has pointed out that " . . . the bulk of the evidence suggests that classical and instrumental conditioning are different forms of ,, . 1earning. . . .
STU'I'IERING: CONDITIONED DISINTEGRATION OF SPEEC.H BEHAVIOR
37
emotional responses and instrumentally conditioned adjustive responses in different, though consonant, theoretical terms (41). Mowrer thought that negative emotional conditioning was "problem making" for the orgarrism and that instrumental learning was "problem solving." The secondary drive of fear, for example, was assumed to lead to adjustive attempts at escape and/or avoidance on the part of the organism. Although the attempt to cope with stimuli indicative of forthcoming noxious stimulation may at first be an adaptive instrumental activity, under certain conditions it can ultimately become a useless or even self-destructive behavior pattern. That this important aspect of problem solving has its base in emotional conditioning has been shown clearly in a nt1mber of experiments (16, 9). The shuttle box is representative of procedures used in such experiments. In this situation animals are shocked following presentation of a conditioned stimulus on one side of a shuttle box, and can escape the shock by some instrumental activity such as jumping across a barrier to the other side of the box. After some experience with this situation, most animals go immediately to the nonshock side when the conditioned stimulus is presented. Such instrumental avoidance behavior usually persists even after the experimenter has stopped presenting the shock and even if a highly desirable goal object, such as food for a deprived animal, is available during presentation of the conditioned stimulus (61). Thus, an instrumental avoidance behavior which formerly had been adaptive to an existent or highly probable noxious state may come to be considered maladaptive if (a) the instrumental activity persists after the noxious state is either no longer present or highly unlikely to reoccur and therefore results in the inefficient use of t11e organism's energy, or (b) the instrumental activity does not ultimately result in •the attainment of an available reinforcement, whether a reduction in negative drive or an increase in positive drive. The interactive relationship between classically conditioned emotionality and instrumentally conditioned activity is meaningful to any discussion of stt1ttering, particularly since most speech pathologists define stuttering as an avoidance reaction or response (31, 79, 4). lndeed, the presence of instrumental avoidance behavior has often been considered a vital diagnostic sign of the speechassociated emotionality that, in essence, defines stuttering. Blood-
38
STUTIERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
stein (5) has pointed out, however, that clinically observed stuttering behavior may exist despite the absence of instrumental activity. This finding is consonant with the position taken by a number of prominent and thoughtful speech pathologists that instrumental activity denotes the development of stuttering rather than its existence (71, 55, 74, 6, 75). More recently, it has been pointed out that repetitions and prolongations are the only universally observable characteristics of stuttering behavior upon which a definition can be based (76, 77). Furthermore, Wingate has noted that some of the instrumental responses may involve behaviors which are removed from direct speech activities or disturbances in speech performance. ~hese comments are consistent witl1 the position that is being offered here. We have limited stuttering to that class of fluency failure that results from conditioned negative emotion. Consequently, although instrumental escape or avoidance of noxious stimulation may result from this class of fluency failure, it is not considered to be denotative of stuttering. Instead, it is posited that these responses are the adjustive or ''problem-solving" behaviors that are employed as a means of coping with the noxious state that was the consequence of fluency failure. If these responses are also adaptive, an existent or highly probable noxious condition will be efficiently escaped or avoided without damage or deprivation to the organism. These adaptive responses will lead, therefore, to reinforcement that is organismically integrative. If, o.n the other hand, these responses are maladaptive, a nonexistent or highly improbable noxious state will be wastefully escaped or avoid~d and the consequent reinforcement may result in learning that is organismically nonintegrative and that may actually increase deprivation. Furthermore, maladaptive responses often cause noxio11s environmental consequences. These punishing reactions to the maladaptive behaviors associated with the act of speaking and the speech itself emanate from the external and internal listeners. These unfavorable responses from the listening environment are, in part, the result of interference whicl1 occurs when the maladaptive attempts to escape or to avoid anticipated punishment disturb the speech performance. The instrumental escape or avoidance behaviors employed may, for example, involve phonatory (speaking on inhalation, modification of breath stream or capacity), articulatory (pursing of lips, presetting of articulators, or variation of articula-
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
39
tory positioning), and resonatory (speaki11g nasally or denasally) aspects of speaking. The speech signal and its communicative value may also be reduced by tl1e various instrumentalities tl1at ~peakers may employ to begin, maintain, and terminate their speech responses. Such maladaptive responses may not only elicit discomfort in the listener to an extent that leads to noxious action but may also impede communication because attention to the nonverbal aspects of speech interferes with the causal relationship between the speaker and the listener. But even if this causal series is not directly affected, the instrumental responses te11d, nevertheless, to limit the information available to the listener within a constant unit of time. Fluency, Fluency Failure, and Stuttering As we have seen, both Wischner as well as Shames and Sherrick postulate that stuttering is an instrumental (operant) avoidance response which results from the punishment of normal disfluency. For Wischner the occurrence of disfluency is a normal or benign event rather than a sign of a distressing condition or circumstance. For Shames and Sherrick disfluency is an emitted behavior whose antecedents, though unknown, may be either biological or environmental. In either case, disfluency and stuttering may not have a common etiological origin. Specifically, they say that disfluency is shaped into the degenerate form that is stuttering by determinative factors that may be independent of its initial occurrence. The position that disfluency is normal is based on a number of studies which indicate that children who are considered to be nonstutterers are not perfectly fluent (8, 22). Indeed, the classic investigations of Davis (17, 18, 19) make it evident that the speech of normal young children will display approximately 49 instances of repetition for each 1,000 words that are spoken during free play. As a result of such data it has been suggested that disfluency is normal and does not reflect a circumstance or condition of critical import. Apparently, disfluency has been considered normal both because it may be exhibited by speakers who are not considered stutterers and because it may occur among all speakers during some segments of their running speech activity. It must be pointed out, however,
40
STU'l~"ERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
that the various investigations of disfluency make it abundantly clear that fluency rather than disfluency abounds. Indeed, these studies and others make it evident that the predominant characteristic of speech behavior is fluency and that large segments of speech activity may be void of disfluency. Since speech is predominantly fluent, it seems more appropriate to say that speakers are normally fluent than to suggest that they are normally disfluent. In addition, this more accurate description makes it meaningful to ask about the circumstances and conditions under which fluency fails to occur. Indeed, within this framework it is now inappropriate, a priori, to blandly ignore dysfiuency and to consider it void of meaning. It is certainly probable that some of the fluency failures exhibited by nonstuttering speakers are the direct outgrowth of such factors as errors associated with the initial stages of speech learning, the learning of new or competing speech activities, incomplete neuromuscular maturation of the organs involved in speaking, and constitutional insufficiency. In addition, many data indicate that fluency failt1re is associated with and increases under conditions of n.egative emotion. As we have seen, the experimental investigations of Hill (29), Savoye (50), and Stassi (64) support the contention that pt1nishing stimuli may have a disruptive effect on the fluency of normal speakers. In addition, the clinical reports of Grinker and Speigel (28) make it apparent that men under stress often evidence decreased fluency and increased fluency failure. Even in the investigations of Davis it is reasonable to assume that at various times a degree of heightened negative emotion existed as a result of the interpersonal activity that occurred in the free-play test situation. In this respect, it should be noted that the repetition she observed appeared to be functionally related to such activities as attention getting, coercion, status seeking, criticizing, seeking a privilege, and obtaining social acceptance. Shames and Sherrick have pointed out that these circu1nstances tend to involve what Skinner has called mantling. They further noted that mantling is that form of verbal behavior whose mood is imperative or interrogative and whose occasioning circumstance is " . . . an aversive stimulus or a specific state of deprivation in the speaker" (54, p. 129). The Davis data also make it evident that among the nonstutterers investigated, boys were more likely than girls to be dysfluent. More recently, Stassi (64) has presented experimental data
STUTTERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
41
which showed that males were judged to be significantly more dysfluent under the organismic stress of consistent punishment than were females. Stassi, on the basis of these findings, was led to hypothesize that "the female is less susceptible to disorganization of verbal behavior than is the male" (64, p. 360). This hypothesis is related to the research of Mysak (47), which was directed teward determining why there is a higher probability of stuttering among male children than among female children. Tl1is study investigated whether or not the sex ratio among stutterers resulted because males were held to a higher standard of fluency than females or because males were actually less fluent than females. The study showed that adolescent males were significantly less concerned about the fluency failures of nonstuttering children than were adolescent girls. These data were not consistent, therefore, with the diagnosogenic assumption that males are held to a higher fluency standard and that this standard is i11trojected. As a result it was suggested that the higher probability of stuttering among males, than among females is probably the consequence of their greater degree of fluency failure. The studies reviewed are but a varied sample of those that led to the present contention that dysfluencies are neither void of critical significance nor descriptively characteristic of the speech signal. Within the present framework, the speech of children and adults is normally fluent; fluency failure-the disruption of fluent speech behavior-is the result of those conditions or sets of conditions that interfere with normal organismic functioning. In other words, there are many roads to organismic stress, and the consequence of each may be the disintegration of fluent speech behavior. Thus, when fluency iailure is observed, this event should be taken as evidence of some disruption of functioning in the organism rather than as a meaningless chance occurrence. The conditions leading to fluency failure may be unlearned or learned. The disruption of fluency which occurs as a result of such factors as fatigue, drug intoxication, and pain is obviously not based on learning. The fluency failures that result from such conditions are not typjcally considered to be stuttering by the members of the society in which the speaker lives or by the speech pathologists that are members of his particular culture. This may well be because almost every speaker has, at one time or another, experienced or
42
STU'I"IERING: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
been told of experiences in which a temporary but significant increase in fluency failure resulted from various unlearned conditions of organismic stress. As a result of such experiences there exists a ready acceptance of the sporadic speech disruptions that are, for example, associated with temporary emotional, fatigue, and drug states. This acceptance is withdrawn by both the professional and nonprofessional listener, however, when the excessive fluency failures are chronically present under circumstances that are not considered an adequate cause for a stress reaction. The presence of fluency failure under these conditions is considered deviant because in these circumstances mo.st speakers are normally fluent. It is the task of the diagnostician to determine the condition or set of conditions upon which the fluency failure depends. This differential determination may lead the diagnostician to state that the organismic stress of specific emotional or organic events is disrupting the normal accuracy of the speech signal. He may, on the other hand, indicate that though the individual's fluency failures are fundamentally the result of an organic pathology, their continued occurrence has ultimately led to conditioned emotionality and speech disruptions whose causative antecedents are different but intertwined. In any event, the differential labels that are diagnostically attached to exhibited fluency failures do not represent meaningless differences. These labels reflect the fact that fluency failures do result from existent conditions that may vary widely and that tl1e course of behavior modification may depend on changes in the currently operating disruptors of the speech· signal. In summary, it has been posited that fluency failure may result from various forms of organismic stress and that stuttering is but one class of fluency disruption. It has also been postulated that the term stuttering should be applied by pathologists only when the disr11ptions of speech fluency significantly exceed the individual's usual level of disfiuency, when the fluency failures are chronic rather than sporadic in their presence, and when the disorganizations are dependent upon conditioned negative emotion whose very existence and magnitude is inappropriate to the stimulus situation. As a caution a point of clarification is needed. Throughout tl1is chapter we have spoken, for purposes of emphasis, as if a nearly direct relationship exists between the occurrence of negative emo-
STU'l"l'ERING: CONDITIONED DISINTEGRATION OF SPEECH :BEHAVIOR
43
tion and fluency failure. Actually, while studies clearly indicate a statistically significant relationship between these two phenomena, not everyone commits fluency failure every time he speaks under conditions of negative emotion. Quite to the contrary, as we have already pointed out, neither stuttering nor fluency is perfectly predictable, suggesting dearly the operation of several, if not many, causative factors. Bibliography 1. Anderson, 0. D., and H. S. Liddell, "Observations on experimental neurosis in sheep," Arch. N eurol. Psychiat" 34: 330-54, 1935. 2. , and R. Parmenter, "A long time study of the experimental neurosis in the sheep and dog," Psychosom. Med. Monogr., 2: Nos. 3 and 4, 1941. 3. Biggs, Barbara E., and Joseph Sheehan, "Punishment or distraction? Operant stuttering revisited," unpublished manuscript, U.C.L.A., 1967. 4. Bloodstein, 0., "Stuttering as an anticipatory struggle reaction," in J. Eisenson (ed.), Stuttering: A Symposium, Harper, New York, 3-69, 1958. 5. , "The development of stuttering: I. Changes in nine basic features," ] .S.H.D., 25:219-37, 1960. 6. , "The development of stuttering: 11. Developmental phases," ].S.H.D ..1 25:366-76, 1960. 7. , and E. J. Brutten, "Stuttering Problems," in R. W . Reiber, and R. S. Brubaker (eds.), Speech Pathology, North-Holland Publishing Co., Amsterdam, 1966. 8. Branscom, M., J. Hughes, and E. Oxtoby, "Studies of non-fluency in the speech of preschool children," in W. Johnson (ed.), Stuttering in Children and Adults, Univ. of Minn. Press, Minneapolis, 157-80, 1955. 9. Brogden, W. J., E. A. Lipman, and E. Culler, "The role of incentive in conditioning and extinction," Amer. ]. Psychol., 51:109-17, 1938. IO. Brown, S. F., "The influence of grammatical function on the incidence of stuttering," ].S.D., 2:207-15, 1937. 11. , "The loci of stutterings in the speech sequence," ].S.D., 10: 181-92, 1945. 12. Brutten, E. J., "A colorimetric anxiety measure of stuttering and expectancy adaptation," Ph.D. Diss., Univ. of Ill., 1957. 13. , "Palmar sweat investigation of disfluency and expectancy adaptation," ].S.H.R., 6:40-48, 1963. 14. , and B. B. Gray, "Effect of word cue removal on adaptation and adjacency: A clinical paradigm," ].S.H.D., 26:385-89, 1961.
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STUTIERfNG: CONDITIONED DISINTEGRATION OF SPEECH BEHAVIOR
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STUTTERING: CONDITIONEP DISINTEGRATION OF SPEECH BEHAVIOR
50. Savoye, A. L., "The effect of the Skinner-Estes operant conditioning
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punishment paradigm upon the production of non-fluencies in normal speakers," M.S. Thesis, Univ. of Pitt., 1959. Scl1aef, R. A. , "The use of questions to elicit stuttering adaptation," ].S.H.D., 20:262-65, 1955. Seward, J. P., "Experimental evidence for the motivating function of reward," Psycho[. Bull., 48:130-49, 1951. , "Introduction to a theory of motivation in learning," Psychol. Rev., 59:405-13, 1952. Shames, G., and C. Sherrick, "A discussion of non-fluency and stuttering as operant behavior," ].S.H.D., 28:3-18, 1963. Sheehan, J. G., "Conflict theory of stuttering," in J. Eisenson (ed.), Stuttering: A Symposium, Harper, New York, 1958. , P. A. Cortese, and R. G. Harley, "Guilt, shame, and graphic projections of stuttering," ].S.H.D., 27:129-39, 1962. Siegeli G. M., R. R. Martin, and E. H. Henrickson, "Experimental control of stuttering behavior, Progress Report I: Control of nonfluency in normal speakers," unpublished manuscript, Univ. of Minn., 1963.
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learning: The outcomes of several extinction procedures with dogs," ]. Ab. Soc. Psych., 48:291-302, 1953. , and L. C. Wynne, "Traumatic avoidance learning: The principles of anxiety conservation and partial irreversibility," Psychol. Rev., 61: 353-85, 1954. Spence, K. W., Behavior Theory and Conditioning, Yale Univ. Press, New Haven, 1956. Stassi, E. J., "Disfluency of normal speakers and reinforcement," ].S.H.R., 4:358-61, 1961. Stevens, M. M., "The effect of positive and negative i:einforcement on specific disfluency responses of normal-speaking college males," Ph.D. Diss., Univ. of Iowa, 1963. Strother, C., "A study of the extent of dysynergia occurring during the stuttering spasm," Psychol. Monogr., 49: 108-27, 1937. Travis, L. E., "A study of the horizontal disintegration of breathing during stuttering," Arch. Speech, 1:157-70, 1936.
68. Van Riper, C., "Study of the thoracic breathing of stutterers during
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73.
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81. 82.
47
expectancy and occurrence of stuttering spams," ].S.D.,, l :61-72, 1936. , "The effect of penalty upon the frequency of stuttering spasms," ]. Genet. Psychol., 50: 193-95, 1937. , "The preparatory set in stuttering," ].S.D., 2: 149-54, 1937. , Speech Correction: Principles and Practice, Prentice-Hall, New York, 1954. , and K. Hull, "The quantitative measurement of the effect of certain situations on stuttering," in W. Johnson (ed.), Stuttering in Children and Adults, Univ. of Min11. Press, Minneapolis, 199-206, 1955. , and R. L. Milisen, "A Study of the predicted duration of the stutterer's blocks as related to tl1eir actual duration," ].S.D., 4:339-46, 1939. West, R., M. Ansberry, and A. Carr, The Rehabilitation of Speech, Harper, New York, 1957. Wingate, M. E., "Evaluation and stuttering, Part I: Speecl1 characteristics of young children," ].S.H.D., 27:106-15, 1962. , "Evaluation and stuttering, Part III: Identification of stuttering and the use of a label," J.S.H.D.! 27:368, 377, 1962. , "A standard definition of stuttering," ].S.H.D., 29:484-89, 1964. Wischner, G. ]., "Stuttering behavior and learning: A program of research," Ph.D. Diss., Univ. of Iowa, 1947. , ''Stuttering behavior and learning: A preliminary theoretical formulation," ).S.H.D., 15:324-35, 1950. , "Anxiety-reduction as reinforcement in maladaptive bel1avior: Evidence in stutterer's represe.n tations of the moment of difficulty," ]. Ab. Soc. Psychol., 47:566-71, 1952. , "An experimental study of some verbal cues as instigators to stuttering behavior," unpublished manuscript, Univ. of Pitt., 1956. Wolpe, J., Psychotherapy by Reciprocal Inhibition, Stanford Univ. Press, Stanford, 1958.
CHAPTER
PREDISPOSING FACTORS
Although learning is involved in the development of stuttering, unlearned predisposing factors may also be important in determining it. However, the statement that both learned and unlearned factors play a role in the development of stuttering ultimately leads to the debate on the effects of heredity versus those of environment. This debate raged hotly among behavioral scientists for many years, and most of them concluded that both heredity and environment contribute to the determination of behavior. Most theorists concerned with stuttering have directed their attention to the environmental influences and have failed to consider the organism in which learning takes place or the possible interaction between environmental and hereditary factors. As a result these theorists have neglected not only the possibility of genetic determination but also the possibility of constitutional determination that is not genetic. In this respect, we should point out that no matter what position is taken on the relationship between heredity and stuttering, it remains possible that other constitutional, but not hereditary, factors may contribute to this behavior. Thus, the rejection of hereditary causation does not mean the rejection of all organic determination.• •The term organic, as used here, denotes not only clearly defined organs of the body but also functional organizations, such as neurological processes.
49
50
PREDISPOSING FACTORS
Theories of the etiology of stuttering have ranged from strongly organic (15, 35) to strongly environmentalistic (38, 13, 28, 27) and some have involved a combination of these two frames of reference (32, 37). For some years now the environmental point of view has been in ascendency, and most contemporary theorists advocate this position. The fact that stuttering behavior has been markedly reduced or completely resolved without known organic change and the fact tl1at changes have occurred with therapy emphasizing environmental principles validates, to some extent, the environmentalist's position. In addition, as we have already mentioned, fluency failures tend to occur under conditions of emotional stress. This evidence implies that fluency failure is related to experience. Furthermo1·e, although there are data suggesting that stuttering is, in part, constitutionally determined, the correlations indicated by these data are not perfect, which implies that other factors have a significant influence. Taken together, these points strengthen the environmental position considerably. To maintain the environmentalistic position, however, the theoretician must account for stuttering or its absence on the basis of experience. But even strong environmentalists find it hard to uncover the experiences underlying stuttering in some cases. Furthermore, many children subjected to noxious conditions or consistent punishment directly related to speech do not develop chronic fluency failure. Organic theorists maintain that the strictly environmentalistic position is weakened by not being able to explain these phenomena and that variables necessary to the understanding of the development of stuttering have been omitted in most of the environmental approaches. One of the primary bases for hypothesizing constitutional determination is the evidence that stt1ttering tends to run across generations in families (34, 36, 12). Environmentalists, of course, point out that such data are not direct evidence that stuttering is inherited since social characteristics, such as religious preference and attitud~, also tend to run in families (13). Nelson's (18) data, however, indicate that stuttering tends to occt1r in children with a family history of stuttering even when the children have not had any direct contact with the stuttering family members. This suggests that direct imitation or influence is not a significant factor. Furthermore, if social influence were the sole determinant of stut~
PREDISPOSING FACTORS
51
tering it would be difficult to explain both stuttering in the absence of familial history and the absence of stuttering where there is such a history (37). The relationship between genetic factors and stuttering is further supported by data indicating that this behavior occurs with significantly greater frequency in both members of monozygotic twin pairs than in both members of dizygotic twin pairs. These data were collected by Nelson, Hunter. and Walter (20), who examined 200 twin pairs, 69 monozygotic and 131 dizygotic. Stuttering was identified in 10 pairs of the monozygotic group and in 30 pairs of the dizygotic group. Of the 10 pairs of monozygotic stuttering twins, stuttering was found in both members of 9 pairs. Of the 30 pairs of dizygotic stuttering twins, stuttering was found in both members of only 2 pairs. Assuming that environmental influences are approximately the same for monozygotic and dizygotic twins, these data command considerable support for the point of view that heredity plays an important part in the development of stuttering. Nelson's (19) data concerning the relationship between the onset of stuttering and family history of stuttering also support this hypothesis. Nelson made a three-generation analysis of the pedigrees of 204 stutterers and 204 matched nonstutterers. She divided her subjects into those whose families showed a "stuttering strain" and those whose families showed a "nonstuttering strain!' The fact that 104 of the stutterers, but only 4 of the matched nonstutterers, came from families with a stuttering strain is in itself quite suggestive. It is perhaps even more important, however, that Nelson found that significantly more stutterers from stuttering strains than those from nonstuttering strains began to stutter at the same time they began to speak. It follows, of course, chat significantly more of the stutterers from nonstuttering strains than those from stuttering strains began stuttering some time after the onset of speech. Furthermore, there is an indication in Nelson's data that if stuttering first · appears after the onset of speech, that is, after the first year of speaking, it is more likely to be reported as related to some traumatic event such as an accident, operation, or illness than if it occurs coincidentally with the onset of speech, particularly in children from fa mi lies showing no stuttering strain. There is thus a fairly clear implication in Nelson's data of the existence of inherited constitutional factors which (a) increase the probability
52
PREDISPOSING FACTORS
that stuttering will occur, (b) increase the probability of stuttering beginning coincidentally with the onset of speech, and (c) make the development of stuttering somewhat less dependent on traumatic contributory experiences. It is also important to consider constitutional factors that may influence the learning of emotional behavior and that may thus be related to the disintegration of fluent speech. One such factor is evident in the fact that stuttering is found more often in males than in females (16, 25, 26). This sex difference in the frequency of stuttering is ust1ally interpreted by envitonmentalists as resulting from a differential attitude which favors the female child (13). However, data recently published by Eisenson (7) suggest that the sex ratio for American stutterers also exists in cultures where there is little difference in attitude toward male and female children. These data throw doubt on the environmentalistic hypothesis concerning the sex ratio of stuttering. '\/Ve must therefore at least consider the alternate hypothesis that such differences are sex-linked and that stuttering is in part constitutionally determined, perhaps because of a differential susceptibility to emotionally induced disorganization. At first glance, the hypothesis that sex differences among stutterers are a function of constitutional factors might seem most startling. There is, however, a considerable amount of tangentially supportive data. For example, the male child is less likely than the female to survive the birth process, is more likely to contract most diseases, and is more likely to have a shorter life span (24). From birth to death, the male appears to be at a disadvantage. A relationship between constitutional factors and emotional learning is also suggested by research on activity level. Observations of children from birth through the early years of childhood have indicated that there are stable individual differences in activity level (29, 4, 2, 3). These differences in activity level suggest an important variance in the threshold of responding. With respect to this, Wolpe (39) points out that a highly responsive child faced with conditions leading to negative emotional reaction is more likely to have a greater extent and intensity of conditioned anxiety than one whose reactivity level is low. Furthermore, research has shown that highly anxious individuals condition more readily and are more susceptible to maladaptive emotional learning (33, 39). Baron's (1) data, for example, indicate that stutterers condition
PREDISPOSING FACTORS
53
more readily during speecl1 activity than during nonspeaking circumstances. Baron assumed that this difference was tl1e result of an increase in the drive level because of speech-associated anxiety. Finally, Pavlov has pointed out that botl1 people and animals differ in conditionability (22). Individuals differ in autonomic reactivity too, so that a given amount of 11oxious stimulation may result in unequal amotints 0£ autonomic upheaval. Eysenck (8, 9, I 0) indicates that these individual differences in conditionability and autonomic reactivity involve the personality dimensions of intraversion and neuroticism, respectively. He indicates also that the interaction at the extrem.es of these dimensions (dysthemia) results in a person almost predestined to stiffer from anxiety, conditioned fears, and phobic behavior. Franks (11) suggests that dysthemia is related to excessive central excitation, which is presumably constitutional. This excessive central excitation results in a tendency toward anxiety, overt sensitivity to the environment, hyperactivity, and hesitancy. The data of Jost and Sontag (14) suggest that these individual differences in autonomic reactivity may be, at least in part, hereditarily determined. These researchers measured the difference in autonomic functioning between siblings and unrelated children. Though their sample size was small, it was apparent that for the functions tested, siblings were less alike than twins, and unrelated children were less alike than siblings and twins. These results may help to explain the previously mentioned data that revealed a similar association between genetic relatedness and stuttering. That autonomic reactivity, conditionability, and the acquisition of anxiety responses are related, and that they are in part constitutionally determined, may be important to an understanding of fluency failure. They are clearly relevant to our hypothesis that the conditioning of anxiety responses is one of the primary variables in the disorganization of fluent speech and the development of stuttering. Furthermore, whether these constitutionally cletermined individual differences are genetic or nongenetic, they probably figure in the learning of stuttering. There are considerable data, then, to support the idea that constitutional factors play some role in the development of stuttering. These same data, however, can also be interpreted to mean that nongenetic factors are involved. For example, in Nelson's (19) data,
54
PREDISPOSING FACTORS
although only 2 per cent of the nonstutterers showed a family history of stt1ttering compared to 51 per cent of the stutterers, it must also be pointed out that the families of 49 per cent of the stutterers sl1owed no evidence of a stuttering strain. This last finding, by itself, might tempt us to say that there is as much evidence for nongenetic determination of stuttering as there is for genetic determination. Also, although most of the other data we have cited suggest a constitutio11al component, they certainly do not indicate that it is tl1e sole cause of stuttering. Problems in interpretation of such biological data usually arise when statistical studies show evidence of a positive correlation between two phenomena but where no specific pl1ysiological mechanisms or processes that explain the data have been discovered. Interpretation is even more difficult wl1en the correlations are far less tha11 perfect, a situation that usually s11ggest$ the operation of variables not accounted for in the measurement proceclures. There is thus con£usio11 over the interpretation of the demonstrated relationsl1ips and over the causes of the 11nexplained variance. The most reasonable solution to this confusion, at least in regarcl to sttlttering, is the recognition that both constitutional and experiential factors are usually involved in its development. It also appears that tl1e amount of variance contributed by each of these sets of factors may fluctuate over a wide range from case to case. There is, thus, probably no set or predetermined amou11t of variance contributed by either constitution or experience from case to case; that is, there is not always tl1e same amount of variance contributed by constitutional factors or by experiential factors. Instead, we can expect to find different amounts of variance contributed by these factors i11 different cases. Thus~ in some cases, an organic predisposition may be so strong that only slightly undesirable co11ditions in the environment may create fluency failure. This is apparently the situation in the cases from Nelson's study, whicl1 indicates a tendency for children from families with a stuttering strain to begi11 stuttering coincidentally with the onset of speech and without severe experiential trauma. In other cases, wl1ere the organic predisposition is not so strong, only severe undesirable environmental conditions will produce failure in fluent speech. This situation is suggested by Nelson's cases of children from nonstuttering family strains who began to stutter later and
PREDISPOSING FACTORS
55
apparently in conjunction with traumatic experiences. In other words, there are botl1 constitutional and learned factors wl1ich may interact to produce stuttering. Given a certain level of constitutional predisposition, experience may increase or decrease the probability that stuttering will occur. Stressful experiences may produce stuttering in a relatively adequate organism, whereas even positive experience may be unable to compensal:e for grossly inadequate organic functioning. l\tfeehl (17) has taken a similar position concerning the interaction between heredity and experience in the etiology of schizophrenia. He h as, however, taken a slightly harder stand on the constitutional cleterminants by postt1lating that they are "specific etiological factors," that is, a necessary but not sufficient determinant. H stuttering were approached in this way, it would mean that this form of fluency failure could develop only in organisms that have some deficiency in 01·ganic functioning. Without this condition, no matter how perverse an individual's experience, stuttering could not develop. Given slight organic deficiency, a strong contribution f1·om experie11ce would be required. But given severe organic deficiency, only a small contribution would be required from experience. At this point there are no data that clearly indicate either that stutterers are universally found to be organically defective or that stuttering consistently develops in indivicluals of su1)erior constitution who are subjected to intensely negative experience. This issue begs for more adequate study of stutterers and for experimentation with conditions leading to fluency failure in nonstutterers with no familial history 0£ stuttering. The interactionist position we have taken here is by no means a new one. Van Riper's (32) recognition tl1at fluency failure ca11 result from constitutional inadequacy and West's (37) postt1lation that constitutional weakness or dysphemia leads to stuttering when triggered by emotional factors have been a part of the literature for many years. The current trend, however, toward an overdependence on environmentalistic explanations requires a restatement of the interactionist position. This seems to be all tl1e more necessary in the light of the more recent data concerned with the effects oh learned behavior of neurophysiological processes such as arousal and activation levels (23, 5), conditionability (31, 30, IO, 11), and limbic
56
PREDISPOSING FACTORS
centers of positive reinforcement (21) and aversiveness (6). Although none of the research in t11ese areas is yet definitive, it clearly implies that experience does not lead simply and directly to learned behavior. Instead, experience appears to interact with organismic variables that also play a role in the shaping of observed behavior. Individual differences, then, are a function not only of unique experience but also of the idiosyncratic combination of experiential and constitutional factors. From this interactionist position it should be clear that the diagnosis of stuttering shotild include a more thorough analysis of organic variables than is now the case. Our hypothesis concerning direct neurophysiological factors argues for neurological work-ups in addition to the customary cursory examination of peripheral speech-associatecl organs. Of course, present knowledge and means for measuring such nem·ological processes are limited, so that diagnostic possibilities in this area are restricted. This, however, is no excuse for the viTtuaJly complete rejection of neu1-ological measure1nent in contemporary research and clinical practice. At this point we argue that the assumptions regarding strictly environmental determination are likely erroneot1s, have led to gross neglect of possibly important determiners of stt1ttering, and have prematurely closed off research a11d development of potentially useful diagnostic and clinical procedt1res. We are fully aware that these hypotheses are presently difficult to test because of limitations in the kI1owledge of neurological processes. Bttt we also wish to point out that the present rejection of neurological factors as a diagnostic consideration was based primarily on the failure of neurology in the 1930's to provide answers to questions raised at that time. Neurophysiological measurement has progressed considerably since then. This progress st1ggests the need for reconsideration of this area. Our hypotheses concerning indirect constitutionally determined factors also argue for diagnostic procedt1res now completely absent from co11temporary practice. Here, we have claimed that such variables as conclitionability, at1tonomic arousal, and behavioral activity level may possibly have a bearing on the development of stuttering. If these l1ypotheses are valid, it is also likely that such processes play a part in the modification of stuttering. Thus, to the extent that diagnosis implies measure1nent for the purpose of determining
PREDISPOSING FACTORS
57
therapeutic strategy, knowledge concerning tl1ese variables is vitally • nnportant. At this point we must anticipate th.e argument that since both direct and indirect constitutional factors are organic, they are unresponsive to treatment and thus unworthy of serious consideration at the level of clinical practice. Here agai11 we must point out that this pessimism or sense of futility arose from the limitations of neurophysiology in tl1e past. While limitations still exist, striking progress has been made. Control of epileptic seizures, red11ction of behavioral 11yperactivity, modification of mood, and rehabilitation of behavioral functions lost or disrupted through neurological trauma are now acknowledged as useful treatment procedures. We tht1s argue that the present sterility in this area may be as much a function of attitude as it is of real limitations. In addition, even if the organic factors that we have 11ypothesized to play a role in the determining of stuttering turn 011t to be unresponsive to any form of treatment, it still appears likely that adequate planning for therapy of stuttering will require their measurement. In the sense that these variables may influence the ability of the client to lear11 or in the sense that differential programs for rehabilitative learning may be required, the particular therapeutic programs may depend on the measurement of these dimensions. Bibliography l. Baron, M., "The effect on eyelid conditioning of a speech variable i11 stutterers and nonstutterers," Ph.D. Diss., Univ. of Iowa, 1949. 2. Birns, B., "Individual differences in human neonates," unpublisl1ed manuscript, N.I.M.H. Grant No., MF-10, 992, 1-10, 1963. 3. Bridger, W. H., and B. Birns, "Neonates' behavioral and autonomic responses to stress during soothing," Recent Ad. Biol. Psychiat., 5: 1-6, 1963. 4. , and M. F. Reiser, "Psychophysiologic studies of tl1e neonate: An approach toward the methodology and theoretical problems involved," Psychosom. Med., 21 :265-76, 1959. 5. Delafresnaye, J. F. (ed.), Brain Mechanisms and Learning,, Thomas, Springfield, 1961. 6. Delgado, J. M. R., W. W. Roberts, and N. E. Miller, "Learning motivated by electrical stimulation of tl1e brain," Amer. ]. Physiol., 179: 587 -93, 1954.
58
PREDISPOSING FACTORS
7. Eisenson, J., "Observations 011 the incidence of stuttering in a special culture," A.S.H.A., 5:772, 1963. 8. Eysenck, H. J., Th.e Structure of Human Personality, Methuen, London, 1953. 9. , Dynamics of Anxiety and Hysteria, Routledge, London, 1957. 10. , Beliavior Therapy and the Neuroses, Pergamon, New York, 1960. 11. Franks, C. M., "Conditio11ing and abnorn1al behavior," in H. J. Eysenck (ed.), Handbook of Abnormal Psychology, Basic Books, New York, 1961. 12. Gray, M., "Tl1e X family: A clinical and laborar.0ry study of a 'stuttering' family," ). Speecli Dis., 5:343-48, 1940. 13. Johnson, W., et al., Speech Handicapped Scliool Children, Harper, New York, 1956. 14. Jost, H., a11d L. W. Sontag, "The genetic factor in autonomic nervous system fi.1nction," Psychosom. lVIed., 6:308-10, 1944. 15. Karlin, I. W., "Stuttering: Basically an organic disorder," Logos, 2:6163, 1959. 16. Loutitt, G. E., and E. C. Hall, "A survey of speech defects among the public school children of Indiana," j.S.D., 1:73-80, 1936. 17. Meehl, P. E., "Schizotaxia, schizotypy, schizophrenia," Amer. Psychologist, 17:827-38, 1962. 18. Nelson, S. E., "Personal contact as a factor in the transfer of stutteri11g," Hitman Biol., 11:393-418, 1936. 19. , "Tl1e role of heredity in stuttering," ]. Pediat., 14:642-54, 1939. 20. , N. Hunter, and lYI. Walter, "Stuttering i11 twin types," ].S.D., 10:335-43, 1945. 21. Olds, J., and P. Milner, "Positive reinforcement produced by electrical stimttlation of septal area and other regions of rat brain," ]. Comp. Physiol. Psychol., 47:419-427, 1954. 22. Pavlov, I. P., Conditioned Refiexes, Clarendon, Oxford, 1927. 23. Ramey, E. R., and D. S. O'Dol1erty, Electrical Studies on the Unanesthetized Brain, Haeber, New York, 1960. 24. Scl1einfeld, A., Wo1(1.en and Men, Harcourt, New York, 1943. 25. Schuell, I-1., "Sex differences in relation to stuttering: Part I," ].S.D., 11: 277-98, 1946.
, "Sex diffei·e11ces ii1 relation to stuttering: Part II," ].S.D. 12:23-28, 1947. 27. Shames, G. 1 and C. Sl1errick., "A discussion of non-fluency and stuttering as operant behavior," ].S.H.D., 28:3-18, 1963. 28. She.eh.a n, J. G., "Conflict theory of stuttering," in J. Eisen son (ed.), Stuttering: A symposi1tm, Harper, New York, 1958. 26.
PREDISPOSING FACTORS
59
29. Shirley, M. :tvf. "Tl1e first two years: ..\. study of twenty-five babies," J-Velfare ''longr., Vol. 3. U11iv. of ~1inn. Press, l\Jinneapolis, 1933. 30. Spence, I
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72
A THEORY FOR THE MODIFICATION OF STUTTERING
oral readings until the response activity did not differ significantly among the three speaking conditions. Indeed, by as soon as the third oral reading there was no significant difference between the frequency of stuttering in the relatively high drive circumstances of speaking before an audience or into a telephone and the low drive condition of speaking to tl1e examiner. The contention that the initial level of performance is partly determi11ed by the drive level has been given further support by a series of investigations utilizing the Palmar Sweat Index (P.S.l.) as an independent measure of negative emotion. These studies were also concerned with the relationship between the initial level of performance a11d the rapidity with which stuttering declined during massed oral reading. The first of these studies was conducted by Brutten (8), who was concerned with the similarities and differences in the performance of stutterers ancl nonstutterers. The results, as seen in Figure IV-2, make it evident that although the stutterers had more fluency failures than the nonstutterers, both samples adapted significantly. Moreover, the stutterers also displayed a higher initial freqtiency of fluency failure and significantly more negative emotion than the nonstutterers. Tl1ese differences in the trial-one fluency failures of stutterers and nonstutterers are important to our contention that the degree of adaptation is a function of the magnitude of dysfluency on the initial trial. Figure IV-2 offers striking support for this relationship since there was a greater degree of adaptation for the stutterers than for the nonstutterers. As a matter of fact, the median frequency of fluency failures over the seven oral trials showed a decremental slope of 22 degrees £01· the stutterer and only 9 degrees for the nonstutterer. * Tl1at the slope of adaptation is a function of the initial level of fluency failure is also shown in Figure IV-3. Here we see that differences in the i11itial pe1·formance level of tl1ree severity groups were associated with differences in the degree o( adaptation; the mild stutterers showed an adaptational decline of 10 degrees, the moderate stutterers a decline of 28 degrees, and the severe stutterers one of 57 degrees. This relationship is also sup• Tl1e angle of the slope was formed by connecting the median points of the first and seventh oral reading trials and then by drawing a horizontal line through point seve11. The reference circle or arrow of the protractor was then placed so as to correspond with point seven and the horizontal line drawn througl1 it. The degree slope is determined by noting where the line connecting points one and seven crosses the marked arc of t11e protractor.
73
A THEORY FOR THE MODIFICATION OF STUTTERING 30 Stutterers Fluency Failure - Palmar Sweating - Non stutterers
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