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61.
This research examines how maximizers make decisions when they must trade-off between desirability and feasibility attributes. Across four studies, we demonstrate that maximizers tend to prefer choices offering more desirability to those offering more feasibility and respond more favorably to a product's advertising when it highlights desirability more than feasibility attributes. Furthermore, we show that maximizers' focus on outcomes rather than processes drives their preference for desirability, such that changing from an outcome to a process focus can redirect their interest from desirability to feasibility. By contrast, satisficers do not prefer products higher in desirability to those higher in feasibility and are not more receptive to ads highlighting desirability attributes. Furthermore, because satisficers may focus on both the outcome and the process, priming either one is redundant and does not alter their preference for desirability or feasibility.  相似文献   
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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   
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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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