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71.
This note presents the hypothesis than the excessively forceful closure of the mouth of larynx associated with certain types of stuttering may involve a neurological confusion between speech and the human body's Valsalva mechanism, which is designed to increase pulmonary pressure by forceful closure of the upper airway to assist in many types of physical effort. It is suggested that such behavior may result from excessive neuromotor tuning of the Valsalva mechanism prior to speech, especially in situations where the stutterer anticipates the need to “try hard” to speak properly. Such tuning may both interfere with phonation and render the Valsalva mechanism overexcitable to triggering stimuli, such as the increase in subglottal pressure that accompanies the start of articulation. 相似文献
72.
The attitudes of 674 speech-language pathologists toward stuttering, stutterers, stuttering therapy, parents of stutterers, and related issues were studied during the years 1973–1983. During that period, clinician attitudes were found to shift away from support of the John-sonian concepts, which suggest parental causality and dangers in early intervention. In addition, clinicians became less likely to perceive stutterers as possessing psychologic disorders and misperceptions of their problem and of their interpersonal relationships. However, a significant number of clinician's were found to continue to hold unsubstantiated beliefs regarding the personality of stutterers, their parents, and the efficacy of early intervention with very young stutterers. The results of the study were interpreted as suggesting the need to educate fluency specialists. 相似文献
73.
Norma Colburn 《Journal of Fluency Disorders》1985,10(1):51-58
The clustering of disfluency within early utterances in the speech of four nonstuttering children was examined. During the developmental period their mean length of utterance was between 2.25 and 3.0 morphemes. The frequency and characteristics of the clustered disfluencies are described and compared with single disfluent moments. Clusters of two disfluencies were analyzed for interactive effects of positional preference and type. Results were similar to those found in older preschool nonstuttering speakers, demonstrating the normal developmental nature of clustering in early sentences. Implications for using this temporal measure to differentially diagnose normal from abnormal disfluency are discussed. 相似文献
74.
75.
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. 相似文献
76.
77.
Three samples of different levels of mental ability, but each of average or above- average intelligence, were administered a battery of reaction time test which measure the speed with which persons can execute various elementary cognitive processes. Discriminant analyses revealed significant differences between the groups in reaction times and intraindividual standard deviations, and univariate analyses indicated that higher ability groups tended to obtain significantly faster mean reaction times and to show significantly less intraindividual variability than lower ability groups. Groups which differed the most in mental ability differed to the greatest extent on the more complex reaction time tests but this pattern was reversed for groups which were relatively close in mean IQ. Generally, the results support the hypothesis that speed- of-processing is an important factor unferlying intelligence, but a number of puzzling findings indicate the need for continued research in this area. 相似文献
78.
W V Dube W J McIlvane H A Mackay L T Stoddard 《Journal of the experimental analysis of behavior》1987,47(2):159-175
In an arbitrary matching-to-sample procedure, two mentally retarded subjects learned conditional discriminations with two sets of stimuli. Each set included a spoken name (N1 or N2), an object (O1 or O2), and a printed symbol (S1 or S2). One subject selected conditionally (a) O1 upon N1, and O2 upon N2, and (b) S1 upon O1, and S2 upon O2. The other subject selected conditionally (a) S1 upon N1, and S2 upon N2, and (b) O1 upon S1, and O2 upon S2. For both subjects, selections of O1 and S1 produced one type of food, F1; selections of O2 and S2 produced a different type of food, F2. Both subjects also learned identity-matching performances, selecting O1, O2, S1, S2, F1, and F2 conditionally upon those stimuli as samples; F1 followed selections of O1, S1, and F1; F2 followed selections of O2, S2, and F2. Matching performances consistent with stimulus class formation involving the names, objects, symbols, and foods were demonstrated on probe trials, even though these performances had not been taught explicitly. Next, new objects, X1 and X2, were presented on identity-matching trials, producing F1 and F2, respectively. Without further training, X1 was selected conditionally upon N1, S1, and O1, and X2 was selected upon N2, S2, and O2. When the contingencies were changed so that selections of X1 and X2 were now followed by F2 and F1, respectively, X2 was selected conditionally upon N1, S1, and O1, and X1 was selected upon N2, S2, and O2. Class membership of X1 and X2 had apparently changed. This study provides evidence that reinforcers may become members of stimulus classes, and that new stimuli may become class members through relations with reinforcers. 相似文献
79.
The interaction of stimulus and reinforcer control in complex temporal discrimination. 总被引:2,自引:2,他引:0
Six pigeons were trained in a discrete-trials signal-detection procedure to discriminate between a fixed-duration stimulus (5 s or 20 s) and a set of variable durations ranging from 2.5 s to 57.5 s in steps of 5 s. For each fixed-duration stimulus, the ratio of reinforcer frequencies contingent upon reporting the fixed versus the variable stimulus was systematically manipulated. Detection performance was well controlled by both the stimulus value and the reinforcer ratio. Both the discriminability between the fixed duration and the set of variable durations, and the discriminability between the fixed duration and each of the variable durations, were independent of the reinforcer-frequency ratio when discriminability was measured as log d. The sensitivity of response bias to reinforcement-ratio changes was independent of the value of the fixed duration, but was not independent of the discriminability of the variable durations from the fixed durations. Under current models, discriminability measures in complex temporal discrimination may be independent of biasing manipulations, but bias measures are not independent of stimulus values. 相似文献
80.
DOES EFFORT PLAY A ROLE IN THE EFFECT OF RESPONSE REQUIREMENTS ON DELAYED MATCHING TO SAMPLE? 总被引:2,自引:2,他引:0 下载免费PDF全文
The possible role of "effort" in the accuracy of pigeons' performance on a delayed matching-to-sample procedure was investigated by examining the effects of response requirements that accompanied a trial-initiating stimulus and that accompanied a sample stimulus. In the first experiment, the effect of varying the size of a fixed-ratio requirement for responses during an initiating stimulus was compared to that of varying a similar requirement for responses during the sample stimulus. Accuracy increased reliably with increases in the ratio scheduled during the sample stimulus, but was not significantly affected by increases in the ratio scheduled on the key during the initiating stimulus. In another phase of Experiment 1, sample duration was held constant while the ratio requirement was varied during the initiating stimulus. Again, accuracy of matching to sample was not significantly affected by the size of the ratio scheduled during the initiating stimulus. Experiment 2 provided a systematic replication of these results in another group of pigeons and included a more detailed analysis of responding. These results support the view that increases in sample-response requirement facilitate accuracy of delayed matching by increasing the durations of exposure to the sample stimuli, and do not support a role of effort in the sample-response effect. In Experiment 3, the facilitative effect of responses on the sample but not of those on the initiating stimulus was replicated using a simultaneous matching-to-sample procedure. This finding provides further evidence against an interpretation of response-requirement effects that appeals to effort; the finding also suggests that sample exposure might affect initial discrimination of the sample rather than remembering the sample. 相似文献