Further evaluation of self and peer judgements of speech with delayed auditory feedback

Fifteen undergraduate students recorded a standard reading passage under simultaneous auditory feedback (SAF) and delayed auditory feedback (DAF, 210 ms). These pairs were rated for articulation and fluency differences, reading rate differences, pitch differences, loudness differences, and overall differences in quality of speech by the fifteen speakers and by ten peer judges. Results suggest that naive speakers under DAF form a self-impression of the effects of DAF upon their speech that is not different from the qualitative ratings of independent peer judges. The hypothesis that there was no overall difference between self and peer ratings was not rejected. Implications for the use of DAF as a research or treatment modality, or as both, are discussed.     

Implications of evaluating and intervening with incipient stutterers

A study was conducted to investigate the factors involved in the recovery from incipient stuttering without therapeutic intervention. Fifteen subjects were seen on two occasions, once for an initial evaluation after the reported onset of stuttering, and for a second evaluation to determine if they had recovered or become chronic stutterers. Within the constraints of a small sample, several findings are presented: (1) 80% of the children recovered spontaneously from stuttering, (2) subjects who exhibited more types and frequencies of disfluencies upon onset had a poorer prognosis for recovery, (3) the age of onset, if under 4 years, had little bearing on recovery, and (4) children who were seen professionally soon after disfluency onset had the greatest prognosis for recovery. Possible implications of these results are discussed.     

Cerebral lateralization of visual stimulus recognition in stutterers and fluent speakers

Cerebral lateralization of stutterers and nonstutterers was assessed in terms of choice reaction times to stimuli presented to either the left or right visual hemifield on letter recognition and figure recognition tasks. Reaction times on both tasks were determined before and after a behavioral speech therapy program. Stutterers demonstrated a significant reduction in mean reaction times in the letter recognition task over the course of the therapy program. This change differed significantly from that obtained from stutterers in the figure recognition task. The stutterers' responses were in contrast to the responses of the nonstutterers, who showed no reduction in mean reaction times for the letter or figure recognition tasks. The results were discussed in terms of alterations in aspects of central nervous system processing as a result of participation in the behavioral speech therapy.     

A comparison of syntax in young stutterers and nonstutterers

This study compares the syntactic structure of the spontaneous speech of a small group of stutterers and nonstutterers, using a method of constituent analysis. Speech samples were taped during play sessions with subjects, and the tapes were then transcribed and analyzed according to preselected constituent criteria. The stutterers were in the early stages of stuttering and had been diagnosed as stutterers by experienced clinicians. The method of analysis proved to be highly reliable. Differences were found in the number of complete clauses, the number of complex sentences, and in clause types between the two groups.     

The use of self-efficacy scaling in training student clinicians: Implications for working with stutterers

A scaling technique developed by Bandura for determining an individual's personal performance expectations (self efficacy) was applied to student clinicians working with stutterers. The self-efficacy scores of clinicians conducting treatment increased significantly while the scores of clinicians without treatment experience showed no significant change. As the student clinicians gained clinical experience there appeared to be a corresponding reduction in fear and avoidance of the treatment situation. Clinician fear concerning stuttering treatment appeared to have little relation to performance in treatment as rated by supervisors. The results indicate that self-efficacy scaling may be used to indicate clinician avoidance of working with stuttering clients.     

Vowel duration in stutterers participating in precision fluency shaping

The purpose of this study was to determine the extent to which stutters manipulate vowel duration to achieve fluency after participating in Precision Fluency Shaping. Nine stutterers who read an all-voiced sentence fluently before and after therapy were selected for study. Wide-band spectrograms were made of the initial phrase of the sentences, and vowel durations were computed. Results indicated that extended vowel durations were characteristic of the fluency of stutterers posttherapy. The subject that had the highest rate of disfluency after therapy also had the shortest vowel durations. Clinical implications concerning the importance of speech rate during carryover practice are made.     

Rate reduction strategies used by stutterers and nonstutterers during high- and low-pitched speech

Groups of child and adult normal speakers and stutterers were tested in an habitual condition and in conditions where they were instructed to read aloud at pitches both higher than and lower than normal. Objective measures were made of subjects' fluent reading rate, and vowel and pause durations across conditions. Disfluencies were also counted. Findings revealed that all four subject groups reduced their frequency of disfluency from the habitual to both experimental conditions. These decrements in disfluency were attended by significant reductions in fluent reading rate. Spectrographic analyses revealed that most subjects, regardless of age and speaker characteristic, affected their rate reduction by extending both vowel and pause durations. These results are compatible with those obtained in recent studies and are discussed.     

A perceptual comparison between paired stimulus and single stimulus methods of presentation of the fluent utterances of stutterers

This investigation compared tape recordings containing the fluent utterances of treated stutterers with those of normal speakers as paired stimuli and single stimuli as presented to 20 sophisticated judges. Fluent utterances were obtained from stutterers successfully treated in one of the following programs: (1) Van Riperian, (2) metronome-conditioning speech retraining, (3) delayed auditory feedback, (4) operant conditioning, (5) precision fluency shaping program, and (6) holistic therapy. In addition, a group of partially treated stutterers were included. The original tape recordings containing matched samples of the fluent utterances of a stutterer and normal speaker were presented as paired stimuli. These paired samples were then separated, randomized, and assembled individually on another tape recording and presented as single stimuli to the same judges. The results of the statistical analysis indicated that the fluent utterances of treated stutterers was perceptibly different from the fluent utterances of nonstutterers, regardless of the method of stimulus presentation.     

A comparison of LRT and VOT values between stutterers and nonstutterers

The experiment reported here found no significant group differences in laryngeal reaction time (LRT) and voice onset time (VOT) values. Rank-order correlations between the stutterers' LRT and VOT values were also nonsignificant. A model of the LRT paradigm is presented that (1) allows for systematic assessment of factors possibly contributing to the failure to replicate the often reported LRT group difference, and (2) is useful in examining the relationship between the LRT experimental condition and normal speaking conditions. We argue that two factors were particularly critical to our results. First, simple reaction time procedures included (1) a warning signal that preceded a response signal by a variable 1–3-sec foreperiod, and (2) a single response. We argue that foreperiod durations exceeded the stutterers' speech posture time for a known response. Second, the stuttering severity rating of our experimental group was less severe than ratings in other experiments.     

Stutterer''s scaled attitudes and their prognostic significance in therapy

Thirty individuals who manifested stuttering behavior participated in an intensive therapy program. Measures of pretherapy attitudes on the Attitude and Behavioral Observation Scale, which consists of self-evaluations of attitudes on a scale of five equal-appearing intervals and also two questionnaires, the Iowa Scale of Attitude Toward Stuttering and the Stutterer's Self-Ratings of Reactions to Speech Situations were utilized. These three scales were found to be significantly correlated. A difference score from the Motor Performance Scale, a speech proficiency scale of one to five was completed at pre- and posttherapy, as a measure of the client's success from therapy. Generally, pretherapy attitudes did not correlate significantly with success from therapy.     

Attitude and personality characteristics of older stutterers

Attitude and personality characteristics of 29 stutterers (19 male, 10 female) aged 52–82 yr were assessed using five questionnaires. Results indicate that, while the older stutterers score approximately the same as young adult stutterers on scales assessing approach and performance behaviors, the large majority of older stutterers perceive their stuttering as less handicapping than when they were young adults. Self-perceived personality characteristics of the older stutterers were similar to a group of older nonstutterers. While a few of the subjects had experienced some degree of success as a result of treatment later in life, the majority of the subjects did not currently desire treatment.     

A critical review of a recent decade of stuttering research

The purpose of the present investigation was to catalogue and evaluate portions of the literature on stuttering from 1967 to 1977. Of particular interest was the identification of the research literature. Of 287 articles located and evaluated, 181 were research reports. These reports were categorized according to topics, subject selection, subjects' characteristics, type of research designs and use of randomization, reliability, and statistical methods. Unhappily, many of the faults identified in reviews ten to twenty years earlier tended to persist, and many of the deficiencies recently cited by authorities in the field were found to characterize this literature.     

Brainstem auditory electrical response characteristics of stutterers and nonstutterers: A preliminary report

In the present study, eight adult male stutterers and nonstutterers showed no significant latency or amplitude differences in BSERs recorded in response to monaural and binaural clicks. However, significantly greater variance was found in the stutterers' group under the monaural stimulation condition at click rates of 12/sec and 5/sec. Left and right monaural waveforms were subtracted individually from the binaural waveform. The resultant binaural interaction difference traces were examined to determine auditory tract preference for binaural stimulation. While some subjects from both groups showed no auditory tract preference, it was found that the significant variance between groups for wave V latency was attributable to the subset of stutterers without auditory tract preference. This finding is interpreted as evidence of neurological differences in stutterers' auditory processing at the brainstem level.     

Syntactic influences on stuttering in young child stutterers

This study examined the location and rate of stuttering in the spontaneous speech of nine young stutterers (4.0–6.6 yr) in relation to certain aspects of syntax. It was designed to answer the following questions: Is there more stuttering at clause onset (boundary) than at other points in the clause? Does the type of clause influence rate of stuttering? Is there more stuttering on complex than on simple sentences? The syntactic analysis defined 10 clause types (seven pertaining to complex sentences and three pertaining to simple sentences); clause boundaries (taking into account “filler” words occuring in such positions); and hierarchical constituent structure within sentences. Stuttering was found with significantly greater frequency at clause boundaries than at internal (nonboundary) positions of clauses. This was apparent for nine of the 10 clause types, the exception being complement clauses. The word “and” at the beginning of simple and complex sentences provoked a high rate of stuttering. The hierarchical structure within the clause did not influence the location of stuttering, and sentence complexity was not a factor in the rate of stuttering.     

The early history of the behavior modification of stuttering: From laboratory to clinic

The knowledge of and attitudes toward stuttering of 152 Alabama vocational rehabilitation counselors were studied using the Alabama Rehabilitation Counselors' Attitudes Toward Stuttering (ARCATS) Inventory consisting of 25 true- false statements designed to assess knowledge of stuttering and 15 statements designed to assess attitudes toward stuttering. Counselors were found to perceive stuttering as being significantly vocationally handicapping and amenable to therapy and to perceive stutterers as almost always benefiting from therapy and as being good candidates for vocational rehabilitation. It was concluded that the vocational rehabilitation counselors studied hold attitudes facilitative to the rehabilitation of stutterers.     

Linguistic analysis of a bilingual stutterer

The ultimate test of the adequacy of linguistic models of fluency breakdown is the degree to which they may account for patterns of dysfluency in the speech of a stutterer who is fluent in more than one language. We present the case of an adult bilingual stutterer (Spanish-English), whose spontaneous language in both Spanish and English was structurally analyzed to assess the relationships of phonological and syntactic structure to the frequency and location of fluency breakdown. Our findings suggest that syntax is probably a greater determinant of stuttered moments than is phonology. Additionally, similarities and differences between English and Spanish sentence structure were associated with similarities and differences in the loci of dysfluencies across the two languages. The need for crosslinguistic research utilizing monolingual and bilingual speakers of languages other than English is emphasized.     

Speech timing skills of normally fluent and stuttering children and adults

This study was designed to explore the speech timing skills of normally fluent and stuttering children and adults producing two sentences, ten consecutive times at basal and modified speaking rates. Spectrographic displays of subjects' utterances in both conditions were made in order to obtain consonant, vowel, pause, and utterance duration measures. Results showed that (1) the two groups of children produced speech durational values similar to those of the two adult groups and (3) there were no consistent between- and within-group differences in the basal and modified rate conditions. Findings are discussed in terms of methodological and sampling differences that exist between the present study and past research on stutterers' speech production abilities.