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901.
Effects of effort on response rate   总被引:2,自引:2,他引:0       下载免费PDF全文
Pigeons were trained to peck for food reinforcement, and the minimum effective force for a peck was varied. In a single-key situation, the response rate was unaffected up to a certain force value, beyond which increments caused a proportional decrement in response rate. Transient enhancement and suppression effects were observed following a change in the force requirement. A change from a high force requirement to a low force requirement resulted in a temporary enhancement of response rate above the stable performance level, whereas a change from a low to a high requirement produced a temporary suppression of the rate below the stable rate. In a two-key situation, the response rate on a key with a given force remained unaffected by the force requirement on the other key. When the rate of response was plotted against the required force, the resultant function was remarkably similar to that obtained from the single-key experiment. When the rates of reinforcement on the two keys differed, the decrement in response rate produced by an increase in the force requirement was proportionally greater on the key with the lower rate of reinforcement.  相似文献   
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Two doses diethylpropion, one dose pipradrol, one dose amobarbital and placebo were administered to 116 subjects, who rated their state on twenty variables. The variables were intercorrelated under pipradrol and pentymal. The correlation matrices were subjected to factor analysis. Four factors were found in both studies: Happiness, Alertness, Relaxation, and Flight of thoughts. There is some agreement between the two factor analyses. There were few significant effects of the drugs on factor scores, but the structure is quite unambiguous: pipradrol and diethylpropion are stimulating, and amobarbital tranquilizing.  相似文献   
909.
Response latencies in naming objects   总被引:16,自引:0,他引:16  
After some preliminary analysis of what is involved in naming objects, in which the possible role of classificatory systems in the memory store is discussed, it is shown experimentally that there are consistent differences between the times taken to respond to presented objects by uttering their names, variations between the performances of different individuals being outweighed by variations due to the different objects. Moreover, there is a high consistency between different individuals as to the ordering of objects in respect of their naming latencies. It is further shown that a high correlation exists between the time taken to name an object and the frequency with which its name occurs in the language as a whole, as estimated in the Thorndike-Lorge Word List. Some implications of these findings are discussed, especially with reference to possible mechanisms by which presented objects are visually identified, and the appropriate names retrieved from the “word-store.”  相似文献   
910.
Memory performance awareness in younger and older adults   总被引:2,自引:0,他引:2  
Reports on the course of memory-monitoring skills across adulthood are discrepant in conclusions and limited in scope. The purpose of this study was to build a large data base (3 samples and 7 different tasks) to assess performance awareness. Younger (19-41 years) and older (59-93 years) Ss estimated performance either before (i.e., predictions) or after (i.e., postdictions) completing each task. Predictions were less accurate than postdictions at both age levels, suggesting Ss monitored performance during the study-test cycle. Overall, the data suggested no consistent age effects in performance awareness: Age differences in monitoring occurred only in predictions and only for some tasks. Between-tasks differences in age effects could not be attributed to a single mediating mechanism like those suggested in previous reports. Why previous research has produced conflicting conclusions about metacognitive development in adulthood is discussed in light of these data.  相似文献   
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