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151.
Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings.  相似文献   
152.
The behavior-regulation approach to learned performance has been the subject of misapprehension and disagreement concerning: (1) the nature and importance of behavior regulation, (2) the definition and role of behavioral set-points, (3) the relation of optimal schedule performance to behavioral set-points, and (4) the question of whether deviations from total responding or from response patterns are the primary determinant of molar responding under schedule constraint. After clarifying the nature and role of behavior regulation and set-points, this paper shows that the data used to question optimal schedule performance (Allison, 1981a) actually strongly support the general behavior-regulation approach. These data also indicate a role for response-pattern set-points in determining schedule behavior, but contradict the hypothesis that deviations from response-pattern characteristics are the primary determinant of molar schedule effects.  相似文献   
153.
Transfer of matching-to-figure samples in the pigeon   总被引:2,自引:1,他引:1       下载免费PDF全文
Three pigeons were trained on a modified six-key matching-to-sample procedure. The third peck on the figure-sample key (which presented a bird, hand, face, beetle, rabbit, fish, flower, or red hue, as the sample) lighted only one comparison key. Every three additional pecks on the sample lighted another comparison key, up to a maximum of five keys. Pecks on keys of matching figures produced grain. Pecks on nonmatching keys (mismatches) turned off all lights on the comparison keys and repeated the trial. Three figures were used during acquisition. The birds learned to peck each sample until the matching comparison stimulus appeared on one of three comparison stimulus keys, and then to peck that key. Later, five novel stimuli, employed as both sample and comparison stimuli, and two additional matching keys were added. Each bird showed matching transfer to the novel samples. The data suggest that the birds may have learned the concept of figure matching rather than a series of two-component chains or discrete five-key discriminations.  相似文献   
154.
Rats' lever pressing produced sucrose reinforcers on a variable-interval schedule where, in different conditions, the duration of a stimulus presented immediately after reinforcement was either correlated or uncorrelated with the duration of the current interreinforcement interval. Under the baseline schedule, in which no stimulus was presented, the minimum interreinforcement interval was 8 s and the mean postreinforcement pause of each subject approximated this value. Response rates increased slowly over the first 10 to 15 s and then remained roughly constant throughout the remainder of the interval. In both the correlated and uncorrelated conditions, the added stimulus resulted in the postreinforcement pauses lengthening to values in excess of the duration of the preceding stimulus. This resulted in a poststimulus pause which was, in most cases, roughly constant irrespective of the duration of the preceding stimulus, or of the reinforcement contingencies prevailing immediately after stimulus offset. Local response-rate patterns in the uncorrelated conditions were similar to those obtained under the baseline schedule in which no stimulus was presented. However, in the correlated condition local response rates increased across the remainder of the interreinforcer interval. Further, the rate of acceleration was inversely related to the duration of the preceding stimulus. These results show that a correlation between stimulus duration and the ensuing time to reinforcement can control behavior—a type of temporal control not previously reported.  相似文献   
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Behavioral conceptions of alcohol abuse often include the hypothesis that drinking behavior is a negatively reinforced operant, with ethanol intoxication viewed as alleviating aversive environmental and internal states. This hypothesis has not been confirmed or refuted by previous studies which employed mild stressors and limited assessment methodology. In the present experiment, 22 patients with severe phobias approached their phobic animal under two consecutive conditions—first while sober and second after drinking either a placebo or an intoxicating dose of ethanol. The severe anxiety induced was assessed behaviorally, physiologically and by the patient's self-report of fear. The intoxicated patients did not experience decreased anxiety, tachycardia or avoidance, compared to the placebo group. These results have clinical implications and suggest the need to reconsider tension-reduction theories of alcohol abuse.  相似文献   
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