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The treatment of stammering in children by the shadowing method
Bchav.
Ra.
B. Therapy.
1967, Vol.
5, pp. 325 to 329.
PCI$WIO~
Press Ltd.
Rioted
in En&nd
THE TREATMENT OF STAMMERING XN CHILDREN BY THE SHADOWING METHOD 0. KONDAS * Department of Psychology, Comenius University, Bratislava, Czechoslovakia (Received 15 November 1966)
Summary-There are very few reports about the application of behaviour therapy to child s~ering
and these are not ~~~a~ng_ Remedial education treatment is foliowed by frequent relapses. The present work gives data about the methods, effects and long-term resufts in nineteen child stammerers treated by the shadowing technique. A discussion of some of the theoretical problems involved is given and shows how the theoreticat analysis influences treatment procedures. Seventy per cent of the cases were successfully treated by the shadowing technique and subsidiary procedures; relapses occurred in only 12 per cent of the eases.
INTRODUCTION THE EXPERIMENTS of Cherry and Sayers (1956) on chronic stammerers have shown that the transference of the auditory perceptions of proper speech might provide a technique for reducing stammering. They concluded that “some of the experiments have suggested methods for training, and show some therapeutic promise”. However, there have been few clinical accounts of their method and follow-up evaluations of the treatment effects have been neglected. Both Cherry and Sayers and Maclaren (1960) examined the immediate influence of “shadowing” on speech fluency in adult stammerers. The application of learning theory to the treatment of childhood stammering is very rare. In his survey on behaviour therapy in children, Raohman (1962) mentions two unsuccessfully treated stammerers; the results in a further three ch.iIdren under operant control were more encouraging. Case (1960) used the method of negative practice in the treatment of stammering in adults with 80 per cent success, and another study was conducted by Walton and Black (1950). The remedial education treatment of child stammering is accompanied by frequent relapses which generally take place during the first months after treatment. For example, Chmelkov;i (1956) recorded a 40 per cent relapse rate; as relapses seem to be one of the most important problems in treating stammering, the present work emphasizes the durabili~ of the (re-)acquired fluent speech.
METHOD Subjects The sample consisted of sixteen children aged between 8 and 16 (X = 10*9), one 20-yr-old student and three children between the ages of 5 and 6. In addition to severe stammering, twelve of the children had frequent speech spasms accompanied by extraneous movements and grimaces. Four of them were unable to speak one whole sentence (they could not communicate verbally and had to write their answers). * Now at: Bratislava, Exniirova I?, Czechoslovakia. 325
326
0. KONDAi
Treatment procedure*
Since pneumographic records of stammerers show irregular and shallow breathing when speaking (Kondas, 1964, p. 160), breathing exercises were carried out during the first two sessions. The exercises consist of a combination of deep and slow inspirations. At the second or third session, exercises in relaxed breathing (similar to those used in autogenic training) were given. The main part of the procedure used in treating the 8 to 16yr-old children was the speech shadowing technique (Cherry and Sayers, 1956). Training in shadowing began in the second or third session. The therapist read an unknown text which was then repeated exactly (‘shadowed’) by the stammerer, one or two words later. One session consisted of two or three short exercises (3-5 min in duration) accompanied by short breaks. As soon as the technique was mastered, daily home-exercises were provided by the parents for about 5 min. To maintain the child’s interest and motivation alternative forms of shadowing (by telephone and by a- voice-cue technique) were used. The modifications were introduced only after the fifth session and thereafter the two forms of shadowing exercises were alternated in the following sessions. At the sixth or seventh session, various aspects of stammering were discussed individually with eight of the older stammerers. In four cases there was insufficient progress towards achieving fluency after ten to fifteen treatment sessions (plus 8-14 weeks of home-exercises) and desensitization treatment was substituted. In the anxiety hierarchies, stress was placed on everyday talking situations such as talking with schoolfellows, parents, teachers, strangers, answering questions etc. For three young children the shadowing technique was adapted into a play form. Using a puppet-show the child was told that we were going to teach him how to play with puppets. After a short training in puppet-movements, the therapist functioned as a prompter and the little stammerer as an actor who spoke for the puppet. “Scenes” were used at home, too, three times a week, and the parents were asked not to pay attention to stuttering moments. The results from this group are evaluated separately. All the treatment was provided on an out-patient basis. Criteria for evaluation
The main criterion
of evaluation
was the frequency of stammers and hesitations Additional information was obtained from a clinical evaluation of the patient’s speech as judged by the following scheme. 0. No effect, i.e. some changes in stammering frequency, but stammering still frequent and speech still not fluent. 1. Little improved-frequency of stammers decreased after treatment but fluent speech was still absent. 2. Much improved-stammering disappeared from current speech; patient speaks fluently most of the time with occasional loss of fluency. 3. Cured-speech is completely fluent; people cannot tell that the child was a stammerer (some slowness of speech may eventually appear). The same scheme was used in the follow-up evaluation. All but four cases were assessed l-2 months after the termination of treatment. In a follow-up evaluation five cases were assessed by the therapist, and the speech of the others was described by parents and by school-teachers. In all but one case the follow-up evaluation lasted over 3 yr with 5 yr as the maximal interval. ( = errors) during shadowing and natural talking.
l
The main characteristics
of the procedure are the same as described formerly in Slovak (Kondag, 1964)
THE TREATMENT OF STAMMERING IN CHILDREN BY THE SH#iDOWING METHOD
327
The average duration of the follow-up was 3.2 yr; four cases were followed for 5 yr, eight cases for from 3 to 4 yr, four cases for 2 yr, and the last case 1 yr. The three young children (not included in Table 1) were followed for from 1 to 4 yr. RESULTS Only one patient experienced difficulty in learning the shadowing method which was mastered quickly by most of the children. Mild cases (3-5 stammers per min) showed some improvement in talking within 3 weeks of shadowing practice. In nine cases, 2 months of practice was needed before improvements emerged but in five cases the duration of treatment was 6-9 months. The frequency of therapeutic sessions was however decreased from once a week to once a fortnight or once every 3 weeks. A reduction in stammering frequency during shadowing appears from the very beginning of practice. The difference in frequency of errors between the first and fifth session with shadowing are statistically significant (PC OWS). At the termination of therapy, or 1 month later, the frequency of stammers and hesitations decreased from 12.2 to 2.2. The difference is statistically significant (t= 3.478, P
Cured
-
Much Combined Slightly improved % improved
Combined Unimproved %
Shadowing method (II= 17) (a) after therapy
9
3
70.6
3
2
29.4
(b) foliow-up
8
2
58.8
2
5
41.2
7
IS
53.7
19
Remedial and skep therapy fn=41)* (a) afkr tkrap~
-
46-3
* Follow-up evaluation was not given.
The data in Table 1 show that ‘70 per cent of cases were successfully treated by the shadowing technique and subsidiary procedures. This is 17 per cent more than the figure obtained with intensive in-patient remedial treatment combined with sleep therapy. Only ‘cured’ and ‘much improved’ cases are taken as successful. It should be mentioned that one of our unimproved cases was feeble-minded (IQ 58). The follow-up evaluation shows that the successful effects of the treatment are markedly stable. only one of the nine ‘cured’ patients showed some slight relapse 2 yr and 5 months E
328
0. KONDAS
after the end of the treatment. He ascribed it to an excessive fear of a class-teacher at technical school. In the ‘much improved’ group, one case became worse 10 months after treatment, and further treatment over the course of a month produced another temporary improvement. The case of the university student is interesting in one respect. He finished his studies, speaking fluently except when he drank wine-this was not considered to be a relapse. In the whole group relapses appeared in 12 per cent of cases, while Zahfilkov& and Zima (1956) mentioned one relapse shortly after termination and three cases who relapsed while still in hospital. The group of three young children treated by a modified form of shadowing were much improved or cured after only 3-5 sessions with the therapist and 3-6 weeks of homeexercises. Their speech was quite fluent and is unchanged after periods from 1 to 3 yr post-treatment.
DISCUSSION
AND CONCLUSIONS
Cherry and Sayers (1956) and other authors have studied the inhibition of stammering by the transference of auditory perceptions, Their work supports the hypothesis that stammering is related to defayed auditory feedback and that ‘the det~i~ng defects here invoived are perceptual rather than motor’. Shadowing and other techniques of auditory perceptual distraction were shown to have a positive effect on stammering. Cherry and Sayers suggested that some of their techniques might provide a means for treating stammering and the present data support their claim. The inhibition of stammering became evident in the course of the first few exercises. The transfer of speech fluency from the shadowing condition to the normal speech behaviour follows somewhat later, and in this connection some problems arise. From the learning standpoint, the speech-shadowing technique seems to represent a method of positive practice. The fluent speech which develops during shadowing is seifreinforced and fluent verba behaviour is thereby established. The transfer of fluent speech from shadowing to the conditions of natural talking still remains a serious problem because speech in the shadowing situation does not provide for the active formulation of proper sentences or the communicative character of speech. Another obstacle may arise from the patient’s fear of some speech situations. Shadowing in the presence of another person, the training of regular breathing while reading and speaking, desensitization treatment and some negative practice, too, may be considered as helpful means for overcoming some of these problems and for ensuring successful transfer. A fear of talking and the subsequent approach-avoidance conilict which may arise are well-known features of the secondary stammering. It is also known that the stammerer avoids words which have become cues for stammering or fluency failure. These cues probably play a role in the generalization of stammer errors and specific word cues of past disfiuency may (according to Brutten and Gray, 1961) “elicit adjacent stuttering where it had not previously existed”. In one of our previous cases who had had considerable word-cueconnected stammers even during shadowing practice, some special shadowing exercises were provided in Latin and this type of failure then disappeared (Kondas, 1964, p. 162). The durability of improved speech depends on the gradient of generalization, and on subsequent reinforcement of speech fluency by everyday events. Therefore, the fluency of current taIking (and not of shadowing) was used as a criterion for te~nating treatment.
T?fE TREATMENT OF STAMhfERXNG IN CHILDREN BY THE SHADOWING
METHOD
329
Shadowing-speech fluency was re5ected.m the decreasing frequency of exercises required. Home-exercises were, however, continued once a week during the month following the completion of the treatment. Under these arrangements the effect of the treatment seems to be satisfactory from the standpoint of its durability. The relapses were substantialIy less than under remedial education treatment. Although the critical interval for relapses is the first year after treatment they sometimes occur even later. In Cherry and Sayers (Eysenck, 1960) article, Marland included seven child stammerers among her case illustrations. Fifty-seven per cent of them were successfully treated. Our results (70 per cent) are better. Thus, the shadowing technique seems to be a useful form of treatment for stammering in children. The play-form modification of shadowing has proved to be a feasible, natural and successful method for very young children. The durability of the improvements achieved by the above procedures is considered to be one of the most important results of the present work. The results confirm Eysenck and Rachman’s (1965) belief that “some method used in treating this condition in adults may prove more successful” in children than the reported attempts to overcome stuttering by de~nsiti~tion. REFERENCES BRUTTENE. J. and GRAYB. B. (1961) Effect of word we removal on adaptation and adjacency: A clinical paradigm. J. Speech Hearing Dis. X,385-389. CASEH. W. (1960) Therapeutic methods in stuttering and speech blocking. In Behaviour Z%erapy and the Neuroses, (Ed. EY~ENCK11. J.). Pergamon Press, Oxford. EYSENCKH. J. (1960) Eehaviour Therapy am-2the Neuroses. Pergamon Press, Oxford. EY~ENCKH. J. and RACHMANS. (1965) The Causes and Cures of Neurosis. Routledge & Kegan Paul, London. CHERRY C. and SAYERS B. McA. (1956) Experiments upon the total inhibition of stammering by external control and some clinical results. J. psychosom. Res. 1,233-246. Reprinted in Behaviour Kkrapy aad fhe Neuroses (Ed. EY~ENCKH. J.). Pergamon Press, Oxford (1960). cbhfELKOV~ A. (1956) Skupinova terapie koktavosti (Group therapy of sling). Cr. Logo&, 202-203. Stat. Pedagog. Naklad., Praha. KOND& 0. (1964) Podiel ucenia v psychoterapii (i% Roie of learn& in Psychotherapy). Vyd. Slav. Akademie vied. Bra&lava. KONDA~0. (1965) Princip interferencie v discentnej reedukacii balbuties a dyslexie (Principle of interference in discent correction of stammering and reading disability). Psychologica, Sbom. FPUK, 57-68, Bratislava. MACL~~REN J. (1960) The treatment of a stammering by the Cherry-Sayers method: Clinical impressions. In Behviour 7’herapy and the Neuroses, (Ed. E~~ENCKH. J.), pp. 457-%0. Pergamon Press, Oxford (1960). RACHMAN S. (1962) Learning theory and child psychology: Therapeutic possibilities. J. ChildPsychol. Psychiat. 3, 149-163. Reprinted in Experiments in Behaviour Therapy, (Ed. EY~ENCK H. J.). Pergamon Press, Oxford (1964). WAL’IDND. and BLACK D. A. (1958) The application of 1earning theory to the treatment of stammering J. psychosom. Res. 3,170-179. Reprinted in Behaviour Therapy and the Neuroses, (Ed. EY~ENCKH. J.) Pergamon Press, Oxford (1960). ZAHALKOVA-PAVL~VA A. and Z~MAJ. (1956) VyZsledky komplexni I&by spanken u koktavosti (Results of complex sleep therapy in stammering). Cs. Lagopedie, 197-201. Stat. Pedagog. Naklad., Praha.
Ra.
B. Therapy.
1967, Vol.
5, pp. 325 to 329.
PCI$WIO~
Press Ltd.
Rioted
in En&nd
THE TREATMENT OF STAMMERING XN CHILDREN BY THE SHADOWING METHOD 0. KONDAS * Department of Psychology, Comenius University, Bratislava, Czechoslovakia (Received 15 November 1966)
Summary-There are very few reports about the application of behaviour therapy to child s~ering
and these are not ~~~a~ng_ Remedial education treatment is foliowed by frequent relapses. The present work gives data about the methods, effects and long-term resufts in nineteen child stammerers treated by the shadowing technique. A discussion of some of the theoretical problems involved is given and shows how the theoreticat analysis influences treatment procedures. Seventy per cent of the cases were successfully treated by the shadowing technique and subsidiary procedures; relapses occurred in only 12 per cent of the eases.
INTRODUCTION THE EXPERIMENTS of Cherry and Sayers (1956) on chronic stammerers have shown that the transference of the auditory perceptions of proper speech might provide a technique for reducing stammering. They concluded that “some of the experiments have suggested methods for training, and show some therapeutic promise”. However, there have been few clinical accounts of their method and follow-up evaluations of the treatment effects have been neglected. Both Cherry and Sayers and Maclaren (1960) examined the immediate influence of “shadowing” on speech fluency in adult stammerers. The application of learning theory to the treatment of childhood stammering is very rare. In his survey on behaviour therapy in children, Raohman (1962) mentions two unsuccessfully treated stammerers; the results in a further three ch.iIdren under operant control were more encouraging. Case (1960) used the method of negative practice in the treatment of stammering in adults with 80 per cent success, and another study was conducted by Walton and Black (1950). The remedial education treatment of child stammering is accompanied by frequent relapses which generally take place during the first months after treatment. For example, Chmelkov;i (1956) recorded a 40 per cent relapse rate; as relapses seem to be one of the most important problems in treating stammering, the present work emphasizes the durabili~ of the (re-)acquired fluent speech.
METHOD Subjects The sample consisted of sixteen children aged between 8 and 16 (X = 10*9), one 20-yr-old student and three children between the ages of 5 and 6. In addition to severe stammering, twelve of the children had frequent speech spasms accompanied by extraneous movements and grimaces. Four of them were unable to speak one whole sentence (they could not communicate verbally and had to write their answers). * Now at: Bratislava, Exniirova I?, Czechoslovakia. 325
326
0. KONDAi
Treatment procedure*
Since pneumographic records of stammerers show irregular and shallow breathing when speaking (Kondas, 1964, p. 160), breathing exercises were carried out during the first two sessions. The exercises consist of a combination of deep and slow inspirations. At the second or third session, exercises in relaxed breathing (similar to those used in autogenic training) were given. The main part of the procedure used in treating the 8 to 16yr-old children was the speech shadowing technique (Cherry and Sayers, 1956). Training in shadowing began in the second or third session. The therapist read an unknown text which was then repeated exactly (‘shadowed’) by the stammerer, one or two words later. One session consisted of two or three short exercises (3-5 min in duration) accompanied by short breaks. As soon as the technique was mastered, daily home-exercises were provided by the parents for about 5 min. To maintain the child’s interest and motivation alternative forms of shadowing (by telephone and by a- voice-cue technique) were used. The modifications were introduced only after the fifth session and thereafter the two forms of shadowing exercises were alternated in the following sessions. At the sixth or seventh session, various aspects of stammering were discussed individually with eight of the older stammerers. In four cases there was insufficient progress towards achieving fluency after ten to fifteen treatment sessions (plus 8-14 weeks of home-exercises) and desensitization treatment was substituted. In the anxiety hierarchies, stress was placed on everyday talking situations such as talking with schoolfellows, parents, teachers, strangers, answering questions etc. For three young children the shadowing technique was adapted into a play form. Using a puppet-show the child was told that we were going to teach him how to play with puppets. After a short training in puppet-movements, the therapist functioned as a prompter and the little stammerer as an actor who spoke for the puppet. “Scenes” were used at home, too, three times a week, and the parents were asked not to pay attention to stuttering moments. The results from this group are evaluated separately. All the treatment was provided on an out-patient basis. Criteria for evaluation
The main criterion
of evaluation
was the frequency of stammers and hesitations Additional information was obtained from a clinical evaluation of the patient’s speech as judged by the following scheme. 0. No effect, i.e. some changes in stammering frequency, but stammering still frequent and speech still not fluent. 1. Little improved-frequency of stammers decreased after treatment but fluent speech was still absent. 2. Much improved-stammering disappeared from current speech; patient speaks fluently most of the time with occasional loss of fluency. 3. Cured-speech is completely fluent; people cannot tell that the child was a stammerer (some slowness of speech may eventually appear). The same scheme was used in the follow-up evaluation. All but four cases were assessed l-2 months after the termination of treatment. In a follow-up evaluation five cases were assessed by the therapist, and the speech of the others was described by parents and by school-teachers. In all but one case the follow-up evaluation lasted over 3 yr with 5 yr as the maximal interval. ( = errors) during shadowing and natural talking.
l
The main characteristics
of the procedure are the same as described formerly in Slovak (Kondag, 1964)
THE TREATMENT OF STAMMERING IN CHILDREN BY THE SH#iDOWING METHOD
327
The average duration of the follow-up was 3.2 yr; four cases were followed for 5 yr, eight cases for from 3 to 4 yr, four cases for 2 yr, and the last case 1 yr. The three young children (not included in Table 1) were followed for from 1 to 4 yr. RESULTS Only one patient experienced difficulty in learning the shadowing method which was mastered quickly by most of the children. Mild cases (3-5 stammers per min) showed some improvement in talking within 3 weeks of shadowing practice. In nine cases, 2 months of practice was needed before improvements emerged but in five cases the duration of treatment was 6-9 months. The frequency of therapeutic sessions was however decreased from once a week to once a fortnight or once every 3 weeks. A reduction in stammering frequency during shadowing appears from the very beginning of practice. The difference in frequency of errors between the first and fifth session with shadowing are statistically significant (PC OWS). At the termination of therapy, or 1 month later, the frequency of stammers and hesitations decreased from 12.2 to 2.2. The difference is statistically significant (t= 3.478, P
Cured
-
Much Combined Slightly improved % improved
Combined Unimproved %
Shadowing method (II= 17) (a) after therapy
9
3
70.6
3
2
29.4
(b) foliow-up
8
2
58.8
2
5
41.2
7
IS
53.7
19
Remedial and skep therapy fn=41)* (a) afkr tkrap~
-
46-3
* Follow-up evaluation was not given.
The data in Table 1 show that ‘70 per cent of cases were successfully treated by the shadowing technique and subsidiary procedures. This is 17 per cent more than the figure obtained with intensive in-patient remedial treatment combined with sleep therapy. Only ‘cured’ and ‘much improved’ cases are taken as successful. It should be mentioned that one of our unimproved cases was feeble-minded (IQ 58). The follow-up evaluation shows that the successful effects of the treatment are markedly stable. only one of the nine ‘cured’ patients showed some slight relapse 2 yr and 5 months E
328
0. KONDAS
after the end of the treatment. He ascribed it to an excessive fear of a class-teacher at technical school. In the ‘much improved’ group, one case became worse 10 months after treatment, and further treatment over the course of a month produced another temporary improvement. The case of the university student is interesting in one respect. He finished his studies, speaking fluently except when he drank wine-this was not considered to be a relapse. In the whole group relapses appeared in 12 per cent of cases, while Zahfilkov& and Zima (1956) mentioned one relapse shortly after termination and three cases who relapsed while still in hospital. The group of three young children treated by a modified form of shadowing were much improved or cured after only 3-5 sessions with the therapist and 3-6 weeks of homeexercises. Their speech was quite fluent and is unchanged after periods from 1 to 3 yr post-treatment.
DISCUSSION
AND CONCLUSIONS
Cherry and Sayers (1956) and other authors have studied the inhibition of stammering by the transference of auditory perceptions, Their work supports the hypothesis that stammering is related to defayed auditory feedback and that ‘the det~i~ng defects here invoived are perceptual rather than motor’. Shadowing and other techniques of auditory perceptual distraction were shown to have a positive effect on stammering. Cherry and Sayers suggested that some of their techniques might provide a means for treating stammering and the present data support their claim. The inhibition of stammering became evident in the course of the first few exercises. The transfer of speech fluency from the shadowing condition to the normal speech behaviour follows somewhat later, and in this connection some problems arise. From the learning standpoint, the speech-shadowing technique seems to represent a method of positive practice. The fluent speech which develops during shadowing is seifreinforced and fluent verba behaviour is thereby established. The transfer of fluent speech from shadowing to the conditions of natural talking still remains a serious problem because speech in the shadowing situation does not provide for the active formulation of proper sentences or the communicative character of speech. Another obstacle may arise from the patient’s fear of some speech situations. Shadowing in the presence of another person, the training of regular breathing while reading and speaking, desensitization treatment and some negative practice, too, may be considered as helpful means for overcoming some of these problems and for ensuring successful transfer. A fear of talking and the subsequent approach-avoidance conilict which may arise are well-known features of the secondary stammering. It is also known that the stammerer avoids words which have become cues for stammering or fluency failure. These cues probably play a role in the generalization of stammer errors and specific word cues of past disfiuency may (according to Brutten and Gray, 1961) “elicit adjacent stuttering where it had not previously existed”. In one of our previous cases who had had considerable word-cueconnected stammers even during shadowing practice, some special shadowing exercises were provided in Latin and this type of failure then disappeared (Kondas, 1964, p. 162). The durability of improved speech depends on the gradient of generalization, and on subsequent reinforcement of speech fluency by everyday events. Therefore, the fluency of current taIking (and not of shadowing) was used as a criterion for te~nating treatment.
T?fE TREATMENT OF STAMhfERXNG IN CHILDREN BY THE SHADOWING
METHOD
329
Shadowing-speech fluency was re5ected.m the decreasing frequency of exercises required. Home-exercises were, however, continued once a week during the month following the completion of the treatment. Under these arrangements the effect of the treatment seems to be satisfactory from the standpoint of its durability. The relapses were substantialIy less than under remedial education treatment. Although the critical interval for relapses is the first year after treatment they sometimes occur even later. In Cherry and Sayers (Eysenck, 1960) article, Marland included seven child stammerers among her case illustrations. Fifty-seven per cent of them were successfully treated. Our results (70 per cent) are better. Thus, the shadowing technique seems to be a useful form of treatment for stammering in children. The play-form modification of shadowing has proved to be a feasible, natural and successful method for very young children. The durability of the improvements achieved by the above procedures is considered to be one of the most important results of the present work. The results confirm Eysenck and Rachman’s (1965) belief that “some method used in treating this condition in adults may prove more successful” in children than the reported attempts to overcome stuttering by de~nsiti~tion. REFERENCES BRUTTENE. J. and GRAYB. B. (1961) Effect of word we removal on adaptation and adjacency: A clinical paradigm. J. Speech Hearing Dis. X,385-389. CASEH. W. (1960) Therapeutic methods in stuttering and speech blocking. In Behaviour Z%erapy and the Neuroses, (Ed. EY~ENCK11. J.). Pergamon Press, Oxford. EYSENCKH. J. (1960) Eehaviour Therapy am-2the Neuroses. Pergamon Press, Oxford. EY~ENCKH. J. and RACHMANS. (1965) The Causes and Cures of Neurosis. Routledge & Kegan Paul, London. CHERRY C. and SAYERS B. McA. (1956) Experiments upon the total inhibition of stammering by external control and some clinical results. J. psychosom. Res. 1,233-246. Reprinted in Behaviour Kkrapy aad fhe Neuroses (Ed. EY~ENCKH. J.). Pergamon Press, Oxford (1960). cbhfELKOV~ A. (1956) Skupinova terapie koktavosti (Group therapy of sling). Cr. Logo&, 202-203. Stat. Pedagog. Naklad., Praha. KOND& 0. (1964) Podiel ucenia v psychoterapii (i% Roie of learn& in Psychotherapy). Vyd. Slav. Akademie vied. Bra&lava. KONDA~0. (1965) Princip interferencie v discentnej reedukacii balbuties a dyslexie (Principle of interference in discent correction of stammering and reading disability). Psychologica, Sbom. FPUK, 57-68, Bratislava. MACL~~REN J. (1960) The treatment of a stammering by the Cherry-Sayers method: Clinical impressions. In Behviour 7’herapy and the Neuroses, (Ed. E~~ENCKH. J.), pp. 457-%0. Pergamon Press, Oxford (1960). RACHMAN S. (1962) Learning theory and child psychology: Therapeutic possibilities. J. ChildPsychol. Psychiat. 3, 149-163. Reprinted in Experiments in Behaviour Therapy, (Ed. EY~ENCK H. J.). Pergamon Press, Oxford (1964). WAL’IDND. and BLACK D. A. (1958) The application of 1earning theory to the treatment of stammering J. psychosom. Res. 3,170-179. Reprinted in Behaviour Therapy and the Neuroses, (Ed. EY~ENCKH. J.) Pergamon Press, Oxford (1960). ZAHALKOVA-PAVL~VA A. and Z~MAJ. (1956) VyZsledky komplexni I&by spanken u koktavosti (Results of complex sleep therapy in stammering). Cs. Lagopedie, 197-201. Stat. Pedagog. Naklad., Praha.