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The demands and capacities model
THE DEMANDS AND CAPACITIES MODEL: RESPONSE TO SIEGEL C. WOODRUFF STARKWEATHER, and SHERYL RIDENER GOTTWALD Temple University, Philadelphia, Pennsylvania, U.S.A.
Responses to the recent critical comments of Gerald Siegel to the demands and capacities model are given. A brief history of the model’s development is followed by direct explanations of its empirical support and logical development. It appears that Dr. Siegel may have referred only to one of our publications on the model. His concern about difficulties in measuring capacities is also addressed. Finally, the logic of the model is explicated and a misunderstanding regarding the use of direct therapy is clarified. © 2000 Elsevier Science Inc. Key Words: Stuttering; Demands; Capacities; Children; Prevention
We are pleased for this opportunity to respond to Dr. Siegel’s comments. Several aspects of the demands and capacities model are often misunderstood, and it is a valuable opportunity for us to respond to them. There appear to be two main concerns. One is that the word “capacities” may be too assumptive, when in fact only an aspect of performance is meant. The second concern is not directly addressed, but alludes to a discussion by Ingham and Cordes (1997) in which it is alleged that there is an error of logic in the model. The model was developed in response to E. O. Wilson’s book Sociobiology (1975) and was an attempt to understand the interactions between genetics and environment in the development of stuttering. The interactions between genetics and environment are complex, and Wilson has spelled them out in more detail in a recent book (Consilience, 1998). It is not simply that a behavior is inherited and then either expressed or not, depending on the state of the environment. Instead, general tendencies to respond in certain ways, or to perceive in certain ways, or to be constrained in behavior in certain dimensions are inherited. These tendencies then find more or less expression according to the environmental circumstances of the organism. Thus, there is a continuing dynamic interaction between genetics and environment, and this is the kind of interactive process that the demands and capacities model expresses with regard to stuttering development. Address correspondence to Dr. C. W. Starkweather, 3615 Hamilton St., Philadelphia, PA 19104, U.S.A.
J. FLUENCY DISORD. 25 (2000), 369–375 © 2000 Elsevier Science Inc. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
0094-730X/00/$–see front matter PII S0094-730X(00)00086-3
370
C. W. STARKWEATHER and S. R. GOTTWALD
However, at the time of our first writing, we saw the interactions between genetics and environment less dynamically, and the word “capacity” was used to refer to characteristics within the person that, according to the literature, distinguished stutterers from nonstutterers (e.g., reaction time). An appropriate conclusion for an experimenter to reach on finding such a difference, inter alia, is that the characteristic in question is expressed only minimally in stutterers and is fully expressed in nonstutterers, thus suggesting that the characteristic is a “capacity” that increases the probability of fluent speech. That these characteristics are observable only through the observation of some behavioral performance goes without saying, but that does not mean that they are not present or that consideration of them in understanding stuttering, or in planning therapy, is somehow illogical. Indeed, if this were the case, most behavioral research would have no value. That capacities can be inferred from the observation of some specific behavior is in some cases an interpretation of the scientists who made the original observations, but even when it is not, it is quite reasonable. When it is found, repeatedly, that stutterers have a slower reaction time than nonstutterers, surely one of the explanations for the finding is that stutterers are not able to respond quickly. There may be other explanations, but a diminished capacity for reacting quickly is a logical one from the evidence. So, when Dr. Siegel expresses concern that the word “capacities” has not been formally defined in discussions of the model, he should first consider the original research in which a diminished capacity was recognized. It would be odd, to say the least, to require a more rigorous standard of inference in clinical practice than in the research on which the practice is based. When there was evidence that a particular capacity was diminished in stutterers, we incorporated it, with other similar findings, as part of the model. In the research studies presenting evidence of diminished capacity, the capacity investigated was operationally defined. We have also defined the term in several of our publications (Gottwald & Starkweather, 1995; Gottwald, 1999; Gottwald & Starkweather, 1999). In his critique, Dr. Siegel almost exclusively refers to one of the earliest publications describing the demands and capacities model (Starkweather, Gottwald, & Halfond, 1990). Although that information continues to be applicable, several more recent publications elaborate on the model and may help to clarify some of the inquiries that Dr. Siegel raises (Gottwald & Starkweather, 1995; Gottwald & Starkweather, 1999). For example, in one publication we described the capacity that Dr. Siegel seems most concerned with—motor ability—as “adequate speech motor control to coarticulate smoothly, rapidly, and with minimal effort”. The motor speech skills or capacities described here—coarticulation, speech rate and speech effort— are not mysterious or nebulous. They are easily observed and measured in the clinic setting, contrary to Dr. Siegel’s opinion. Although these observations are of behavior, they are not of fluency itself. Thus, the measures are independent of the construct, contrary to Dr. Siegel’s
DEMANDS AND CAPACITIES RESPONSE
371
suggestion. So it is not circular to measure a child’s speech rate, and to infer, if it is unusually slow, that he may lack one or more of the speech motor control skills that underlie fluency. Nor is it circular to assess a child’s language performance in a certain area, say word-finding, and to conclude that the extra time taken up by the child during this process makes it a little more likely that he might, through reacting to time pressure, begin to struggle in speaking. The same could be said of any of the assessments of capacity. If the literature shows that a certain skill is associated with fluent speech production, clinicians are well advised, on empirical as well as logical grounds, to assess that skill and to see if therapy can be planned in such a way as to increase it. Some skills may not be capable of change through therapy but only through maturity. In such a case, the therapy plan might incorporate alterations of the environment to make it easier for the child to be more fluent. For example, if a child has a slowed reaction time, we may not be able to change that with therapy. But we can modify speech rate and conversational pace in the child’s environment so that they are better matched to the child’s current reaction time capacity. Over time, maturity may increase this capacity, and the environmental modifications can be withdrawn. So it seems clinically useful to assess capacities, even in those cases when there is little that we can do about them. Dr. Siegel expresses concern about perceived difficulties encountered when attempting to formally assess capacities. He suggests that “...part of the clinician’s challenge is to determine a child’s capacity from the fragmentary evidence available in the child’s speech and other behavior”. We agree that any diagnostic process examining a human behavior such as fluency is challenging. But, contrary to Dr. Siegel’s beliefs, we do assess each capacity or skill area separately, not in isolation, but in the context of the act of intentional communication. We assess speech motor skill in several ways. Formal articulation and phonological analysis at the connected speech level provide us with information about the child’s ability to coordinate the oral-motor movements needed for speech. These assessments also provide information about the child’s ability to coarticulate in a smooth, fluid way another motor skill or capacity that contributes to fluency. Diadochokinetic rates are indicative of a child’s ability to maintain oral-motor movements for speech related tasks over time. Speech rate measurements provide insight about the child’s ability to manipulate speech-motor movements quickly and effortlessly. It is not at present practical for most clinicians to administer oral muscle reaction time measures, voice onset time measures, or other, more physiologically based measures of oral and speech motor control, but that does not mean that they are incapable of being measured. Indeed, they were measured in the studies that provided the findings that form the substance of the model, and perhaps with advances in clinical technique or instrumentation it may be practical for clinicians to measure them as part of a fluency assessment. In the meantime some inference may be necessary.
372
C. W. STARKWEATHER and S. R. GOTTWALD
Assessment information is collected in much the same way for the other capacity areas shown by the research to impact fluency. Formal and nonformal measures of language, cognition, and affect are computed to determine the child’s skill levels. This assessment protocol has been most recently described in a text devoted to early stuttering interventions. Another area where Dr. Siegel’s interpretations diverge from ours is related to what may be his simplification of the demands and capacities model. Dr. Siegel says that “...it is assumed that if the environment places undue pressure on any one of these capacities, stuttering may develop.” In reality, it is not the pressure of demands on capacities so much as it is the interaction of demands and capacities. And we certainly have not suggested that “pressure on any one of the capacities” (italics ours) may cause stuttering to develop. Such a simplistic view is far from our belief and quite different form the model as it has been described. Our view is instead considerably more complex and dynamic. A description here may also dispel the somewhat silly notion that the model is illogical. The developing child presents a composite of inherited tendencies, strengths, weaknesses, and perceptions, which together influence the probability that at a given moment he or she may speak disfluently. The literature suggests that certain specific skills based on those characteristics are important in determining the fluency level of a given speaker at a given time. At the same time, there are many environmental variables, which the literature has shown to influence a person’s fluency level at any given moment. There is nothing illogical in categorizing these findings in the literature according to whether they are within the person or external to the person. That separation is the first logical step of the model. The second logical step is to refrain from assuming that these known influences operated independently, but instead to assume that it is probable that all of them are impinging on the developing child at the same time. Thus, forces within the child that make him more likely to stutter are countered by environmental forces that make it less likely that he will stutter at a given moment. Similarly, a lack of some capacity may be countered by a supportive environment. And, of course, it may be that both organismic and environmental influences both summate to make the child more likely to stutter or more likely to be fluent. It is hard to imagine that it could be otherwise. The third logical step in the model is to acknowledge that these forces are not static but change from time to time. It may be that organismic influences change more slowly through maturity, learning, or insight, but they certainly change. Similarly, the environmental and contextual influences also change, and much more rapidly, with alterations in emotional, linguistic, and cognitive variations that take place during the speech act. The fourth logical step is to suggest that each child (or adult for that matter) has a threshold for fluency, and that when positive forces (either environmen-
DEMANDS AND CAPACITIES RESPONSE
373
tal or organismic) outweigh negative ones, the person will be fluent; and when the negative forces outweigh the positive ones, the person will be disfluent. Both normal speakers and stutterers speak with partial fluency. Because these organismic and environmental variables have been identified in the literature as making it more or less likely that the person will speak fluently, it is certainly logical to suggest that a threshold may be present, different of course for different individuals. We acknowledge that empirical support for this aspect of the model is sparse and would welcome research that would confirm or deny it. The final logical step is an assumption, but one easily made in our opinion. It is that the more often this threshold for disfluency is exceeded and the child speaks disfluently, the more opportunities there are for him or her to react with struggle and forcing, or to develop one or more of the various reactive behaviors with which we are all too familiar. Similarly, if one inclines to the operant frame of reference, it is still true that the more opportunities there are for a child to speak disfluently, the more opportunities there are for the child to experience consequences for disfluent speech. Consequently, it is the combined aggregate of environmental and organismic events affecting fluency that increase or decrease the probability that the child will develop stuttering. It seems therefore logical to base treatment on a simultaneous reduction of negative influences and an increase in positive ones. Dr. Siegel, in his comments, suggests that a child’s capacities are not seriously addressed within the framework of the demands and capacities model. He states that, “...in practice, however, capacities usually get short shrift.” If Dr. Siegel had supplemented his literature review with additional resources, including writings published more recently that expand on the clinical application of the demands and capacities model, he would have discovered that the consideration of capacities in therapy is, on our view, as critical as addressing demands (i.e., Gottwald & Starkweather, 1995; Gottwald & Starkweather, 1999). When applying the demands and capacities model to intervention, each child’s treatment program is individualized, because each child and family present with a unique combination of capacities and demands at any given point in time. When considering capacity development, some children will need articulatory support, others will benefit from the development of expressive language skills, while others may work on social communication skills. At the same time, some families may decide that a less hectic schedule or a more structured family turn-taking style will reduce the pressure associated with talking. It is impossible to discuss the modification of demands without an adequate understanding of the strengths and limitations of the child’s capacities. Regarding “direct” therapy, Dr. Siegel states that “Starkweather and his colleagues recognize that reducing demands may not suffice, and direct therapy is sometimes necessary”. A first area of contention with this statement re-
374
C. W. STARKWEATHER and S. R. GOTTWALD
lated to Dr. Siegel’s use of the term “direct therapy.” We assume he is referring to working with the child. The demands and capacities model views the family system, and not the child, as the focus of intervention (i.e., see Gottwald, 1999). Direct therapy refers to all of the components of intervention, including helping families modify their speaking environments, helping caregivers learn new ways to communicate with the child who stutters, and helping the child strengthen fluency skills. In addition, it is not clear how Dr. Siegel acquired this perception about when direct therapy is selected for any particular child. We do not advocate trying just one aspect of the program, and then implementing the second aspect if the first is unsuccessful, as Dr. Siegel suggests. Because we are hoping to develop the best match possible between capacities and demands, we expect to be most successful most rapidly if both capacities and demands are addressed in therapy. In reality, there are many reasons why a clinician would work with the child who stutters while also working with the child’s family. A case example may prove helpful. A 5-year-old boy who had recently begun to stutter came from a highly verbal family. He had two teenage brothers, and both parents held PhDs and professional jobs. When this youngster used longer, more complex sentences, articulatory clarity and fluency decreased. In therapy, we provided this child with many opportunities to practice using longer sentences, first at a much slower speech rate and then gradually increasing rate as the child’s speech production system became more skilled through practice. At the same time, we helped the family to choose conversation topics that were more appropriate for the five-year old, which then reduced the sentence length and complexity used by the adults in the household. So the child’s ability level was strengthened while the environmental models were simplified. We feel that the resultant match between capacities and demands was responsible for this child’s improved fluency. There is one point we will concede. The words “demands” and “capacities” are not as descriptive as we would like. “Capacities” does indeed suggest something inherent, and perhaps static, and in the beginning we were thinking of inherent traits and so came to use the term “capacity.” Later, as we expanded the model, we came to see capacities more as skills that could be learned or modified, a view much closer to contemporary genetic thinking. The term “demands” is also not as descriptive as we would like. It seems to suggest that everything that is environmental has a negative influence. Some environmental variables, of course, enhance fluency.
REFERENCES Gottwald, S.R., & Starkweather, C.W. (1995). Fluency intervention for preschoolers and their families in the public schools. Language, Speech and Hearing Services in the Schools 11, 117–126.
DEMANDS AND CAPACITIES RESPONSE
375
Gottwald, S.R. (1999). Family communication pattern and stuttering development; An analysis of the research literature. In N.B. Ratner & E.C. Healey (Eds.), Stuttering research and practice: Bridging the gap (pp. 175–92). Mahwah, NJ: Lawrence Erlbaum Associates. Gottwald, S.R., & Starkweather, C.W. (1999). Stuttering prevention and early intervention: A multi-process approach. In M. Onslow & A. Packman (Eds.), The Handbook of Early Stuttering Intervention (pp. 53–82). San Diego, CA: Singular Publishing Company. Ingham, R., & Cordes, A. (1997). Self-measurement and evaluating stuttering treatment efficacy. In R.F. Curlee & G.M. Siegel (Eds.), Mature and treatment of stuttering: New directions (2nd ed.) (pp. 413–437). San Diego, CA: Singular Publishing Company. Starkweather, C.W., Gottwald, S.R., & Halfond, M. (1990). Stuttering prevention: A clinical method. Englewood Cliffs, NJ: Prentice-Hall. Wilson, E.O. (1975). Sociobiology: The new synthesis. Cambridge, MA: Belknap Press of Harvard University Press. Wilson, E.O. (1998). Consilience: The unity of knowledge. New York: Vintage Books.
Responses to the recent critical comments of Gerald Siegel to the demands and capacities model are given. A brief history of the model’s development is followed by direct explanations of its empirical support and logical development. It appears that Dr. Siegel may have referred only to one of our publications on the model. His concern about difficulties in measuring capacities is also addressed. Finally, the logic of the model is explicated and a misunderstanding regarding the use of direct therapy is clarified. © 2000 Elsevier Science Inc. Key Words: Stuttering; Demands; Capacities; Children; Prevention
We are pleased for this opportunity to respond to Dr. Siegel’s comments. Several aspects of the demands and capacities model are often misunderstood, and it is a valuable opportunity for us to respond to them. There appear to be two main concerns. One is that the word “capacities” may be too assumptive, when in fact only an aspect of performance is meant. The second concern is not directly addressed, but alludes to a discussion by Ingham and Cordes (1997) in which it is alleged that there is an error of logic in the model. The model was developed in response to E. O. Wilson’s book Sociobiology (1975) and was an attempt to understand the interactions between genetics and environment in the development of stuttering. The interactions between genetics and environment are complex, and Wilson has spelled them out in more detail in a recent book (Consilience, 1998). It is not simply that a behavior is inherited and then either expressed or not, depending on the state of the environment. Instead, general tendencies to respond in certain ways, or to perceive in certain ways, or to be constrained in behavior in certain dimensions are inherited. These tendencies then find more or less expression according to the environmental circumstances of the organism. Thus, there is a continuing dynamic interaction between genetics and environment, and this is the kind of interactive process that the demands and capacities model expresses with regard to stuttering development. Address correspondence to Dr. C. W. Starkweather, 3615 Hamilton St., Philadelphia, PA 19104, U.S.A.
J. FLUENCY DISORD. 25 (2000), 369–375 © 2000 Elsevier Science Inc. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
0094-730X/00/$–see front matter PII S0094-730X(00)00086-3
370
C. W. STARKWEATHER and S. R. GOTTWALD
However, at the time of our first writing, we saw the interactions between genetics and environment less dynamically, and the word “capacity” was used to refer to characteristics within the person that, according to the literature, distinguished stutterers from nonstutterers (e.g., reaction time). An appropriate conclusion for an experimenter to reach on finding such a difference, inter alia, is that the characteristic in question is expressed only minimally in stutterers and is fully expressed in nonstutterers, thus suggesting that the characteristic is a “capacity” that increases the probability of fluent speech. That these characteristics are observable only through the observation of some behavioral performance goes without saying, but that does not mean that they are not present or that consideration of them in understanding stuttering, or in planning therapy, is somehow illogical. Indeed, if this were the case, most behavioral research would have no value. That capacities can be inferred from the observation of some specific behavior is in some cases an interpretation of the scientists who made the original observations, but even when it is not, it is quite reasonable. When it is found, repeatedly, that stutterers have a slower reaction time than nonstutterers, surely one of the explanations for the finding is that stutterers are not able to respond quickly. There may be other explanations, but a diminished capacity for reacting quickly is a logical one from the evidence. So, when Dr. Siegel expresses concern that the word “capacities” has not been formally defined in discussions of the model, he should first consider the original research in which a diminished capacity was recognized. It would be odd, to say the least, to require a more rigorous standard of inference in clinical practice than in the research on which the practice is based. When there was evidence that a particular capacity was diminished in stutterers, we incorporated it, with other similar findings, as part of the model. In the research studies presenting evidence of diminished capacity, the capacity investigated was operationally defined. We have also defined the term in several of our publications (Gottwald & Starkweather, 1995; Gottwald, 1999; Gottwald & Starkweather, 1999). In his critique, Dr. Siegel almost exclusively refers to one of the earliest publications describing the demands and capacities model (Starkweather, Gottwald, & Halfond, 1990). Although that information continues to be applicable, several more recent publications elaborate on the model and may help to clarify some of the inquiries that Dr. Siegel raises (Gottwald & Starkweather, 1995; Gottwald & Starkweather, 1999). For example, in one publication we described the capacity that Dr. Siegel seems most concerned with—motor ability—as “adequate speech motor control to coarticulate smoothly, rapidly, and with minimal effort”. The motor speech skills or capacities described here—coarticulation, speech rate and speech effort— are not mysterious or nebulous. They are easily observed and measured in the clinic setting, contrary to Dr. Siegel’s opinion. Although these observations are of behavior, they are not of fluency itself. Thus, the measures are independent of the construct, contrary to Dr. Siegel’s
DEMANDS AND CAPACITIES RESPONSE
371
suggestion. So it is not circular to measure a child’s speech rate, and to infer, if it is unusually slow, that he may lack one or more of the speech motor control skills that underlie fluency. Nor is it circular to assess a child’s language performance in a certain area, say word-finding, and to conclude that the extra time taken up by the child during this process makes it a little more likely that he might, through reacting to time pressure, begin to struggle in speaking. The same could be said of any of the assessments of capacity. If the literature shows that a certain skill is associated with fluent speech production, clinicians are well advised, on empirical as well as logical grounds, to assess that skill and to see if therapy can be planned in such a way as to increase it. Some skills may not be capable of change through therapy but only through maturity. In such a case, the therapy plan might incorporate alterations of the environment to make it easier for the child to be more fluent. For example, if a child has a slowed reaction time, we may not be able to change that with therapy. But we can modify speech rate and conversational pace in the child’s environment so that they are better matched to the child’s current reaction time capacity. Over time, maturity may increase this capacity, and the environmental modifications can be withdrawn. So it seems clinically useful to assess capacities, even in those cases when there is little that we can do about them. Dr. Siegel expresses concern about perceived difficulties encountered when attempting to formally assess capacities. He suggests that “...part of the clinician’s challenge is to determine a child’s capacity from the fragmentary evidence available in the child’s speech and other behavior”. We agree that any diagnostic process examining a human behavior such as fluency is challenging. But, contrary to Dr. Siegel’s beliefs, we do assess each capacity or skill area separately, not in isolation, but in the context of the act of intentional communication. We assess speech motor skill in several ways. Formal articulation and phonological analysis at the connected speech level provide us with information about the child’s ability to coordinate the oral-motor movements needed for speech. These assessments also provide information about the child’s ability to coarticulate in a smooth, fluid way another motor skill or capacity that contributes to fluency. Diadochokinetic rates are indicative of a child’s ability to maintain oral-motor movements for speech related tasks over time. Speech rate measurements provide insight about the child’s ability to manipulate speech-motor movements quickly and effortlessly. It is not at present practical for most clinicians to administer oral muscle reaction time measures, voice onset time measures, or other, more physiologically based measures of oral and speech motor control, but that does not mean that they are incapable of being measured. Indeed, they were measured in the studies that provided the findings that form the substance of the model, and perhaps with advances in clinical technique or instrumentation it may be practical for clinicians to measure them as part of a fluency assessment. In the meantime some inference may be necessary.
372
C. W. STARKWEATHER and S. R. GOTTWALD
Assessment information is collected in much the same way for the other capacity areas shown by the research to impact fluency. Formal and nonformal measures of language, cognition, and affect are computed to determine the child’s skill levels. This assessment protocol has been most recently described in a text devoted to early stuttering interventions. Another area where Dr. Siegel’s interpretations diverge from ours is related to what may be his simplification of the demands and capacities model. Dr. Siegel says that “...it is assumed that if the environment places undue pressure on any one of these capacities, stuttering may develop.” In reality, it is not the pressure of demands on capacities so much as it is the interaction of demands and capacities. And we certainly have not suggested that “pressure on any one of the capacities” (italics ours) may cause stuttering to develop. Such a simplistic view is far from our belief and quite different form the model as it has been described. Our view is instead considerably more complex and dynamic. A description here may also dispel the somewhat silly notion that the model is illogical. The developing child presents a composite of inherited tendencies, strengths, weaknesses, and perceptions, which together influence the probability that at a given moment he or she may speak disfluently. The literature suggests that certain specific skills based on those characteristics are important in determining the fluency level of a given speaker at a given time. At the same time, there are many environmental variables, which the literature has shown to influence a person’s fluency level at any given moment. There is nothing illogical in categorizing these findings in the literature according to whether they are within the person or external to the person. That separation is the first logical step of the model. The second logical step is to refrain from assuming that these known influences operated independently, but instead to assume that it is probable that all of them are impinging on the developing child at the same time. Thus, forces within the child that make him more likely to stutter are countered by environmental forces that make it less likely that he will stutter at a given moment. Similarly, a lack of some capacity may be countered by a supportive environment. And, of course, it may be that both organismic and environmental influences both summate to make the child more likely to stutter or more likely to be fluent. It is hard to imagine that it could be otherwise. The third logical step in the model is to acknowledge that these forces are not static but change from time to time. It may be that organismic influences change more slowly through maturity, learning, or insight, but they certainly change. Similarly, the environmental and contextual influences also change, and much more rapidly, with alterations in emotional, linguistic, and cognitive variations that take place during the speech act. The fourth logical step is to suggest that each child (or adult for that matter) has a threshold for fluency, and that when positive forces (either environmen-
DEMANDS AND CAPACITIES RESPONSE
373
tal or organismic) outweigh negative ones, the person will be fluent; and when the negative forces outweigh the positive ones, the person will be disfluent. Both normal speakers and stutterers speak with partial fluency. Because these organismic and environmental variables have been identified in the literature as making it more or less likely that the person will speak fluently, it is certainly logical to suggest that a threshold may be present, different of course for different individuals. We acknowledge that empirical support for this aspect of the model is sparse and would welcome research that would confirm or deny it. The final logical step is an assumption, but one easily made in our opinion. It is that the more often this threshold for disfluency is exceeded and the child speaks disfluently, the more opportunities there are for him or her to react with struggle and forcing, or to develop one or more of the various reactive behaviors with which we are all too familiar. Similarly, if one inclines to the operant frame of reference, it is still true that the more opportunities there are for a child to speak disfluently, the more opportunities there are for the child to experience consequences for disfluent speech. Consequently, it is the combined aggregate of environmental and organismic events affecting fluency that increase or decrease the probability that the child will develop stuttering. It seems therefore logical to base treatment on a simultaneous reduction of negative influences and an increase in positive ones. Dr. Siegel, in his comments, suggests that a child’s capacities are not seriously addressed within the framework of the demands and capacities model. He states that, “...in practice, however, capacities usually get short shrift.” If Dr. Siegel had supplemented his literature review with additional resources, including writings published more recently that expand on the clinical application of the demands and capacities model, he would have discovered that the consideration of capacities in therapy is, on our view, as critical as addressing demands (i.e., Gottwald & Starkweather, 1995; Gottwald & Starkweather, 1999). When applying the demands and capacities model to intervention, each child’s treatment program is individualized, because each child and family present with a unique combination of capacities and demands at any given point in time. When considering capacity development, some children will need articulatory support, others will benefit from the development of expressive language skills, while others may work on social communication skills. At the same time, some families may decide that a less hectic schedule or a more structured family turn-taking style will reduce the pressure associated with talking. It is impossible to discuss the modification of demands without an adequate understanding of the strengths and limitations of the child’s capacities. Regarding “direct” therapy, Dr. Siegel states that “Starkweather and his colleagues recognize that reducing demands may not suffice, and direct therapy is sometimes necessary”. A first area of contention with this statement re-
374
C. W. STARKWEATHER and S. R. GOTTWALD
lated to Dr. Siegel’s use of the term “direct therapy.” We assume he is referring to working with the child. The demands and capacities model views the family system, and not the child, as the focus of intervention (i.e., see Gottwald, 1999). Direct therapy refers to all of the components of intervention, including helping families modify their speaking environments, helping caregivers learn new ways to communicate with the child who stutters, and helping the child strengthen fluency skills. In addition, it is not clear how Dr. Siegel acquired this perception about when direct therapy is selected for any particular child. We do not advocate trying just one aspect of the program, and then implementing the second aspect if the first is unsuccessful, as Dr. Siegel suggests. Because we are hoping to develop the best match possible between capacities and demands, we expect to be most successful most rapidly if both capacities and demands are addressed in therapy. In reality, there are many reasons why a clinician would work with the child who stutters while also working with the child’s family. A case example may prove helpful. A 5-year-old boy who had recently begun to stutter came from a highly verbal family. He had two teenage brothers, and both parents held PhDs and professional jobs. When this youngster used longer, more complex sentences, articulatory clarity and fluency decreased. In therapy, we provided this child with many opportunities to practice using longer sentences, first at a much slower speech rate and then gradually increasing rate as the child’s speech production system became more skilled through practice. At the same time, we helped the family to choose conversation topics that were more appropriate for the five-year old, which then reduced the sentence length and complexity used by the adults in the household. So the child’s ability level was strengthened while the environmental models were simplified. We feel that the resultant match between capacities and demands was responsible for this child’s improved fluency. There is one point we will concede. The words “demands” and “capacities” are not as descriptive as we would like. “Capacities” does indeed suggest something inherent, and perhaps static, and in the beginning we were thinking of inherent traits and so came to use the term “capacity.” Later, as we expanded the model, we came to see capacities more as skills that could be learned or modified, a view much closer to contemporary genetic thinking. The term “demands” is also not as descriptive as we would like. It seems to suggest that everything that is environmental has a negative influence. Some environmental variables, of course, enhance fluency.
REFERENCES Gottwald, S.R., & Starkweather, C.W. (1995). Fluency intervention for preschoolers and their families in the public schools. Language, Speech and Hearing Services in the Schools 11, 117–126.
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