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951.
Lesions localized to specific areas of the amygdala and overlying cortex in rats produced differential effects in several behavioral tasks. Three different types of lesions were tested: central, basolateral, and cortex lateral to the amygdala. Lesions restricted to the central nucleus produced increased activity on all parameters studied in an open-field test, but the other two groups were not changed. In one-way active avoidance all three groups with lesions showed deficits. The most pronounced change was observed in the central group. All groups showed the same degree of retention loss, but in forced extinction of one-way active avoidance after retraining, the cortical and basolateral groups were most defective. A fear-reduction hypothesis is proposed for the central lesion. The basolateral and cortical areas may be more specifically involved in passive avoidance behavior.  相似文献   
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Second- and sixth-grade (ages 7 and 11 years, respectively) subjects were instructed to learn simple Spanish vocabulary nouns using the keyword method. To remember a foreign word translation the keyword method user must: (1) associate the foreign word to an English word (the keyword) that sounds like part of the foreign word; and (2) remember an image of the keyword and translation referents interacting. Second-grade keyword users who were provided with interactive pictures remembered more vocabulary items than those who generated their own imagery links when given separate pictures of the keyword and translation referents. Second graders who generated their own linking images when given only the keywords and translation words recalled fewer items than both picture groups, and were not significantly different from control subjects. Sixth graders in the three imagery-link variations performed at comparable levels and better than control subjects. The results are in complete accord with previous speculations about the development of imagery strategies in children.  相似文献   
954.
The discriminative learning and transfer of compound and component problems were assessed in retarded subjects at two levels of intelligence. It was found that brighter subjects (MA = 10 years) found the component problems relatively easier than the compound problems to a greater extent than did the less developed subjects (MA = 5 years). The learning of compound solutions was shown to transfer positively to other compound problems and negatively to component problems. Component solutions were found to transfer positively to other component solutions and negatively to compound solutions. These dimensional transfer effects were interpreted to mean that both compound and component solutions were mediated and conceptual in nature. The developmental differences in relative usages of compound and component aspects of stimuli were viewed as the result of differences in direction of attention rather than of differences in complexity of processing.  相似文献   
955.
Four recently proposed models of confusion are examined within a classification of major types of multiplicative models. It is shown that all four are equivalent within a single confusion matrix but are open to mutual testing across experiments producing two or more confusion matrices. Generalization of these models is considered.  相似文献   
956.
A survey of 96 school psychologists and 75 school superintendents throughout the state of Ohio showed the two groups to have generally similar personal value systems and to be in overall agreement in their respective rankings of school psychology goals. Both groups held the traditional school psychologist's goal of conducting individual testing to be lower relevance than acting as an internal consultant or resource person. Of those differences identified, superintendents assigned greater relevance to values which were consistent with their administrative concerns, while psychologists held values preferring individualism as more relevant. Superintendents held goals associated with increased learning efficiency and interacting with community agencies as more relevant, while psychologists assigned higher relevance to goals associated with parent-psychologist interactions.  相似文献   
957.
Temporal control of behavior: schedule interactions   总被引:1,自引:1,他引:0       下载免费PDF全文
In Experiment I the response that terminated the postreinforcement pauses occurring under a fixed-interval 60-second schedule was reinforced, if the pause duration exceeded 30 seconds. The percentage of such pauses, rather than increasing, decreased. There were complex effects on the discriminative control of the pause by the reinforcer terminating the previous fixed interval, depending on whether the fixed interval and the added reinforcer were the same or different. In Experiments II(a) and II(b), each reinforcement initiated an alternative fixed-interval interresponse-time-greater-than-t-sec schedule, the schedule values being systematically varied. When the response following a pause exceeding a given duration was reinforced, fewer such pauses occurred than when they were not reinforced, i.e., on the comparable simple fixed-interval schedule. There was no systematic relationship between mean interrinforcement interval and duration of the postreinforcement pause. The pause duration initiated by reinforcement was directly related to the dependency controlling the shortest pause at that time, regardless of changes in mean interreinforcement interval.  相似文献   
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