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111.
The present study examined the plasticity of the human perceptual system by means of laboratory training procedures designed to modify the perception of the voicing dimension in synthetic speech stimuli. Although the results of earlier laboratory training studies have been ambiguous, recently Pisoni, Aslin, Perey, and Hennessy (1982) have succeeded in altering the perception of labial stop consonants from a two-way contrast in voicing to a three-way contrast. The present study extended these initial results by demonstrating that experience gained from discrimination training on one place of articulation (e.g., labial) can be transferred to another place of articulation (e.g., alveolar) without any additional training on the specific test stimuli. Quantitative analyses of the identification functions showed that the new perceptual categories were stable and displayed well-defined labeling boundaries between categories. Taken together with the earlier findings, these results imply a greater degree of plasticity in the adult speech processing system than has generally been acknowledged in past studies.  相似文献   
112.
According to frequency theories of concept attainment, acquisition of rule-governed concepts depends on discriminating relevant from irrelevant stimulus features on the basis of their respective frequencies of occurrence. Depending on the theorist, the critical frequency counts may be based on occurrence in all stimuli or on occurrence in positive instances only. Experiment 1 held frequency in positive instances constant and varied the frequency of irrelevant features in the negative category. High frequency was associated with impaired performance, but only when concept problems started with a negative instance. Experiment 2 demonstrated that some previous findings in the literature that were thought to support frequency theory also depended on problems starting with a negative instance. These findings are not easily reconciled with existing frequency theories. We attribute our results to high intercategory similarity, which is a correlate of high frequency of irrelevant features. In the context of a hypothesis-testing theory, we propose that a negative start stimulus proactively interferes with memory for information in the initial positive instance and that the extent of the interference depends on how similar negative instances are to positive instances.  相似文献   
113.
Speech-language clinicians working with the confirmed stuttering client are often faced with the clinical management of the covert symptoms of stuttering in addition to the more observable and measurable overt symptoms. The authors report the successful use of awareness techniques to exaggerate the subjective experience of these covert symptoms and encourage the use of these techniques as an adjunct to the counseling and desensitization procedures traditionally employed. A transcribed clinical management session in which several awareness techniques are used to aid the client in an introspective examination of “anticipation of stuttering,” is analyzed in order to reach some specific recommendations for using awareness techniques in the clinical management of the covert symptoms of stuttering.  相似文献   
114.
In this study, the validation of a Revised Fear Survey Schedule for Children (FSSC-R) is detailed. Psychometric properties of the scale are reported for two normal samples and one clinical sample of school-phobic children. Initial analyses indicate that the FSSC-R possesses high internal consistency, high test-retest reliability and acceptable stability over time. Further, it adequately discriminates between normal and clinical samples, has acceptable convergent and discriminant validity and possesses a meaningful factor structure. The potential clinical utility of the scale is discussed, and important social and developmental issues affecting the development and expression of fear in children are addressed.  相似文献   
115.
A preliminary analysis of the reactions by staff and other residents to the behaviour of mentally-handicapped people living in a medium-sized institution is presented. The subjects' behaviour was categorized as appropriate, inappropriate or neutral according to culturally-normative criteria. It was found that, for the majority of time there was no reaction to the subjects' behaviour by staff or by other residents. The implications of utilizing culturally-normative criteria for categorizing behaviour are discussed. It is proposed that this type of analysis is potentially useful for understanding the nature of interactions in institutions.  相似文献   
116.
The role of marking when reward is delayed   总被引:1,自引:0,他引:1  
Two-choice spatial discrimination by rats is enhanced if a salient stimulus marker occurs immediately after every choice response and again after a delay interval (Lieberman, McIntosh & Thomas, 1979). Three experiments further explore this effect. Experiment 1 found that the second marker is unnecessary. Experiment 2 found that a marker presented before a response is as effective as one presented after. Both effects could be explained in terms of markers focusing attention on subsequent cues. Experiment 3, however, found that markers after choice enhance learning even when no discriminative cues are present following the marker. Markers thus appear to initiate both a backward search through memory and attention to subsequent events; both processes help to identify events that might be related to the unexpected marking stimulus.  相似文献   
117.
Blumstein, Cooper, Goodglass, Statlender, and Gottleib (Brain and Language, 9, 153–170 (1980)) attempt to determine by an examination of the VOTs of aphasic speakers whether Broca's aphasics make phonemic substitutions in addition to their well-known phonetic errors. There are a number of problems with this study, mostly due to an apparent failure to fully appreciate the fact that VOT is a cover term for several acoustic features. It is suggested that VOT measurement in any given position in a word cannot solve this problem and that future studies should include glottographic observations as well as VOT measurements made in all positions in the word.  相似文献   
118.
Interview data were collected from 46 English elderly men (age 70 to 94 years) relating to attitudes, psychological traits, and life satisfaction. Sexual interest was not related to life satisfaction or marital status but was significantly correlated with measures of emotional expressivity, personal identity, as well as regrets about the past. Findings are discussed in terms of Erikson's later stages of ego development.  相似文献   
119.
Four experiments used the visual search paradigm to examine feature integration mechanisms. Reaction time to determine the presence or absence of a conjunctive target is relatively fast and exhaustive for low-density displays. Search rate is slow and self-terminating for high-density displays. Density effects do not arise when the target is defined by a unique feature. Two mechanisms are proposed for feature integration. A fast mechanism integrates features on the basis of coarse location information coded with the initial registration of the features. This coarse location mechanism requires that display items be spaced apart. A second, slower mechanism is used when objects are clumped together. The 2-mechanism hypothesis provides a resolution to conflicting findings in the visual search and illusory-conjunction literature. A possible interpretation of the findings with a single guided search mechanism for feature integration is also discussed.  相似文献   
120.
Albino Sprague-Dawley rats with complete septal lesions and rats with control operations were studied under fixed-ratio (FR) schedules of reinforcement. Both groups were trained for 10 sessions each under FR 10, 20, 40, 60, 80, and 100. In contrast to findings from progressive FR studies and some simple FR studies, septal lesions resulted in lower overall and local response rates along with longer postreinforcement pauses. These effects were especially evident during the FR 100 schedule of reinforcement. A comparison of reinforcement rate as a function of FR size within the context of behavioral economics (i.e., a demand function) indicated that septal lesions did not alter the reward value of food. These findings suggest that responding on FR schedules of reinforcement can be altered by the various procedures used to train rats to reach the terminal value of a reinforcement schedule.  相似文献   
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