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991.
Lever holding into shock and short-latency responses to shock onset are two response patterns that interfere with avoidance acquisition in free-operant and discriminated avoidance situations. In an attempt to eliminate these patterns, an additional timer disabled the lever for a period slightly longer than shock duration. A free-operant avoidance schedule with a warning stimulus, but without the additional timer, constituted the control condition. The lever-disabling timer was turned on by different events in two experimental conditions: (a) release of the lever at the onset of shock, (b) shock onset. Interfering responses diminished most rapidly, and efficient avoidance behavior appeared earliest, when the lever-disabling timer was turned on by shock onset.  相似文献   
992.
Three pigeons were trained to perform a two-key sequential match-to-sample task. During baseline conditions, food reinforcement was contingent upon the first match response to occur following 8-min periods, and orange illumination of both keys preceded the delivery of food by 0.5 sec. The baseline schedule of food reinforcement was in effect throughout the study. In some conditions, a 0.5-sec flash of orange keylight alone was presented contingent upon mismatch responses that followed variable time periods averaging 1 min. Rate of mismatch responses increased and accuracy of matching performances decreased as compared with baseline conditions. The ability of the 0.5-sec orange flash to reinforce mismatch responses was markedly reduced when it no longer immediately preceded the delivery of food.  相似文献   
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The intent of this study was to determine the effects of a clients' need for approval on the outcomes of counseling. The expectation was that clients who have a high need for approval by others would cooperate more with the counseling process and would more often be successful in the sense of being rehabilitated. The Marlowe-Crowne Social Desirability Scale was administered to 167 applicants at a state rehabilitation agency immediately after the initial interview. It was hypothesized that successfully rehabilitated clients would obtain significantly higher social desirability scores than those clients who were not successful. The results confirmed the hypothesis at the .01 level of significance.  相似文献   
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