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141.
Experiments 1 and 2 examined the effects of various durations of lickcontingent delays of reinforcement on the development of schedule-induced polydipsia. Food was provided every 1 min in the absence of licking. Delays of 1 min or more effectively disrupted the development of the licking behavior. In Experiments 3 and 4 a lick-contingent stimulus was provided in addition to the delay of food delivery. A light, which was turned on by a lick and turned off by food, greatly enhanced the development of polydipsia under delays that had previously prevented such development. A tone proved less effective than the light in promoting the development of polydipsia. Adventitious reinforcement and conditioned punishment explanations of these results were considered. A distinction was drawn between the mechanism responsible for the development of schedule-induced behavior and that responsible for its maintenance.  相似文献   
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The hypotheses were investigated that (a) ability to recognize the auditory perceptual stimuli for familiar events is a developmental correlate to language acquisition and (b) the low functioning mentally handicapped suffer from auditory agnosia and are impaired in this ability. The subjects were 42 nonretarded children of ages 3 through 6 and 53 severely and moderately retarded, noninstitutionalized students. The retarded subjects were matched by mental age to the chronological age of the nonretarded children. The stimuli were 49 environmental sounds; the task consisted of sound-and-picture matching-to-sample. Group membership and developmental age were the factors in an analysis of variance design. The results revealed a strong effect of developmental age (p <. 0001). The effect of group was not significant, indicating that auditory agnosia may not be common among the lower functioning retarded. The assumption that agnosia may be a major factor underlying the language disability of the severely retarded was reexamined. It was suggested that the severely retarded achieve the requisite perceptual-semantic knowledge base for language too late, after the critical age for spontaneous and efficient language learning has passed.  相似文献   
144.
Two randomly assigned groups, N = 7 each, of neurologically normal patients were composed. One group, RM, had regional cerebral blood flow measurements during a recognition memory probe test; the other group, SC, had rCBF measurements during a semantic classification task, using the same stimulus and response features as the RM task. Thus, the groups differed only in the cognitive instruction they were executing. The RM group showed a significantly lower change from resting baseline to activation, in mean left hemisphere initial slope index, than did the SC group. The RM group, but not the SC group, showed a significant inverse correlation between occipital flow and accuracy of memory performance as indicated by d′. Correlations between age and hemispheric initial slope index, and between homologous left and right hemisphere sites, were also described. The results are considered to support an anatomical basis for the distinction between episodic and semantic memory and to suggest that occipital flow may diminish with accurate memory performance because of an upstream demand of blood in the medial temporal lobes.  相似文献   
145.
Right CVAs, mild left CVAs, and non-brain-damaged adults received the Token Test under three conditions: quiet, white noise, and speech babble. Left CVAs performed most poorly of all groups in all conditions experiencing difficulty with subtests III, IV, and V. Right CVAs were inferior to controls on each of these three subtests in the speech babble condition only. Thus, right CVA difficulty with both memory and syntactic tasks was demonstrated in speech babble. These results are explained by the hypothesis that both hemispheres are necessary to process auditory information under complex listening conditions. Total brain capacity of right CVA patients may be overloaded if either memory load or linguistic complexity is increased in the presence of certain types of listening competition.  相似文献   
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Papers were reviewed in the sections where their major findings seemed to have the most important implications. Since it typically was not possible to do justice to individual studies in a few lines of summary, readers are referred to the specific articles of their interest for further information regarding other findings.As has been the case in the past several years, the number of studies related to vocational behavior and career development appears to be expanding, along with perceptions of what is relevant to the field. As greater emphasis is placed on the working life of individuals after initial occupational choices are made, researchers on vocational behavior and career development will increasingly find it necessary to synthesize research findings from the areas of industrial/organizational psychology, organizational sociology, and organizational behavior and theory. This factor may suggest greater collaboration among researchers across these fields in the future. In any event, the broadening base of relevant research, while challenging, also is an exciting development with rich potential for increased knowledge of vocational behavior.As Walsh mentioned in his review of 1978 literature, there is a vital need for more work of a longitudinal nature. We see some increase this year, but we are too frequently forced to draw conclusions regarding long-term vocational development from studies which are mainly crosssectional and correlational in nature.Among the research directions of note this year is the increasing emphasis on information processing/decision-making frameworks as a means of studying the vocation development process. Other trends were the growing concern with the relationship between work and nonwork, interest in recruitment processes, and the emphasis on situational as well as individual factors in predicting vocational behavior.  相似文献   
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