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271.
Twenty-eight pigeons were given discrimination training. Four groups were run in which for 0, 2, 4 and 9 sessions of training colour was an irrelevant cue and tone was relevant. Generalization tests were given in extinction; the training colour (C1) and another colour (C2) were presented with tone (T) and noise (N). Responding to these four stimulus combinations, TC1, TC2, NC1 and NC2, allowed the assessment of control by colour and tone. A reduction of control by colour and an increase in control by tone were found to be positively related to the amount of training with colour irrelevant. Tests showed a strong inverse relationship between control by colour and tone.  相似文献   
272.
Four groups of rats received 0, 3, 6 or 9 days of overtraining after having reached stable performance on a continuous reinforcement bar pressing schedule. Half the subjects in each group had previously been designated emotionally reactive or non-reactive in terms of defecation rates in an open-field test. Following training, there were four test days in which bar pressing in each group was examined in the presence or absence of white noise. The major findings were that, in both the reactive and non-reactive groups, white noise produced a fear reaction which significantly depressed bar pressing at low levels of habit strength while having an energizing effect at higher levels. The results were interpreted as supporting Bardach's (1960) hypothesis that anxiety introduced early in practice is more disruptive than when introduced late in practice.  相似文献   
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The relationship between attitudes toward the Vietnam war and willingness to sign a strongly worded and publicized antiwar resolution was studied in a random sample of 131 male college seniors at a selective liberal arts college. Level of opposition to the war did not fully explain why many strongly antiwar subjects did not sign the resolution. With level of opposition to the war held constant, personality measures and other attitudes differentiated between signers and nonsigners It is hypothesized that the disposition to act publicly in support of private attitudes is a separate variable, which may be independent of the content and intensity of attitudes Studies of “activism” should distinguish more sharply between private attitudes and public actions.  相似文献   
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