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In two experiments, hungry rats were given instrumental lever-press training for an appetitive reinforcer and, in addition, were exposed to another type of food which was not contingent on lever pressing. In the first experiment, exposure to each type of food was on separate days, whereas in the second experiment rats were exposed to each type of food in strict alternation within each session. Subsequently, a food aversion was conditioned to the reinforcer for the experimental group and to the non-contingent food for the control group. In both experiments, animals with an aversion to the reinforcer responded less in an extinction test than animals with an aversion to the non-contingent food. Subsequent reacquisition tests confirmed that the aversion to the non-contingent food in the control group was of comparable strength with that to the reinforcer in the experimental group. The results were discussed in terms of whether the reinforcer is encoded in the associative structure set up by exposure to an instrumental contingency.  相似文献   
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Gay marriages (as such) are not as yet allowed anywhere but the demand for them is increasing. Most countries take a liberal attitude towards marriage: few obstacles are put in its way. But objections to gay marriages continue to be raised. These objections are refuted and the case for gay marriage is assessed through the prism of various forms of liberalism. The normative argument for allowing gay marriage is shown to be both strong and consistent with many of the values upheld by the opponents of such unions.  相似文献   
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We test the emotion-response congruency hypothesis, which predicts that the consequences of socially sharing one's negative emotions depend on the congruency between the shared emotion and the response that is obtained from the interaction partner. Experiment 1a shows that the response that people prefer is dependent on the specific emotion shared. Experiment 1b, however, reveals that the responses that interaction partners provide do not differ across emotions. Yet, and crucially, Experiment 2 shows that the outcomes of sharing are affected by the congruency between the response that people receive and the emotion they share, thus supporting the emotion-response congruency hypothesis. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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