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61.
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G. C. Preston A. Dickinson N. J. Mackintosh 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1986,38(2):217-237
Three experiments used a discriminated operant procedure to study conditional discrimination learning in rats. The first experiment showed that rats were capable of learning a biconditional discrimination in which two contexts served as conditional cues signalling the reinforcement contingencies associated with two discriminative stimuli. The discrimination was learned equally well when one discriminative stimulus signalled food, the other its absence, and when one stimulus signalled food, the other extinction plus mild footshock.
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
In Experiment 2 it was shown that prior training on such a conditional discrimination enhanced the subsequent context specificity of simple conditioning relative to control groups of animals for whom the prior training had not been conditional. Experiment 3 showed that a reversal of the significance of one pair of discriminative stimuli produced no spontaneous reversal in performance to a second, target, pair.
The pattern of results is best accounted for by an analysis of contextual conditional discrimination learning in terms of stimulus configurations and offers no support for the notion that rats may learn a general conditional rule or set. 相似文献
63.
We examined the effects of acute psychological stress on lymphocyte proliferation and circulating levels of interleukin-1 and -2. Healthy men were exposed to two viewings of a gruesome surgery film and were asked to recall details of the film twice during a 30-min period. These subjects were compared to a nonstress control group. Lymphocyte proliferation to the mitogen concanavalin A (Con A; 5 micrograms/ml) was decreased during and after exposure to the stressor when compared to the control group. This decrease was more pronounced in subjects exhibiting greater blood pressure reactivity while viewing the film than in subjects showing smaller blood pressure responses. None of the other immunological measures was significantly affected by the stressor. Cortisol was not correlated with lymphocyte responsiveness. Possible explanations for these results and implications for further research are discussed. 相似文献
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This study examined the effect of high and low communication apprehension in conjunction with social and personal settings upon verbal behavior. Step wise multiple discriminant analysis of the data indicated a linear combination of language indices (number of syllables, Noun-Verb/Adjective-Adverb ratio, and phrase repetitions) which discriminated between the high apprehensive-personal setting group and the remaining three groups. Results are discussed relative to theoretical projections and the potential for sensitivity toward communication behavior being operative within the communication apprehension framework. 相似文献
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Although message‐production theories often assume that goals behave dynamically to direct communication behavior, few studies consider the interconnectedness of goals and behavior throughout interactions. Here, the interrelationship of communication goals and tactics was examined through a sequential analysis of 47 conflict interactions between close friends or dating partners. It was posited that for both the initiators and resistors in a conflict, the importance of relational or other‐identity goals would be associated with the use of integrative tactics and the importance of instrumental or self‐identity goals would be related to the use of distributive tactics. We examined these predictions within and across partners. Analyses indicated that for both conflict initiators and resistors, the importance of a combination self/instrumental goal predicted the use of distributive tactics and the importance of an other‐identity goal lead to partner‐oriented tactics. For resistors, the importance of an instrumental goal was associated with the use of distributive tactics and the importance of a combination identity/relational goal was aligned with issue‐oriented tactics as well. Across partners, several significant patterns between one partner’s use of distributive or integrative tactics and the other partner’s goals were observed. Implications of the results for understanding conflict and message production are discussed. 相似文献