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The purpose of this investigation was to further define the role of anxiety sensitivity, in relation to physiological arousal and the cognitive perception of anxiousness, as a determinant of anxiety. One hundred and thirty-two undergraduates at an urban university served as subjects. Two physiological measures of arousal and two cognitive measures of anxiety were used following an anxiety inducing task (mental arithmetic). The general expectation, which was supported, was that individual differences in anxiety sensitivity levels are more closely related to subjects' reported anxiousness in stressful conditions than are the actual physiological changes. Additionally, anxiety sensitivity was related to poststress levels of anxiety whereas trait anxiety was only related to pre- and postrelaxation levels of anxiety. Implications of the findings are addressed. 相似文献
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The presence of nonobservational vocabulary is shown to be necessary for wide application of a conservative principle of theory revision.Support for this research was provided by the Office of Naval Research under contract No. N00014-87-K-0401. We thank Daniel Andler and Clark Glymour for helpful discussion. 相似文献
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Abstract: Do memories change as we acquire new information? Recent research on memory distortion using implicit tests along with research using confidence is reviewed and new studies are presented. Two new studies asked misinformed subjects to provide reasons for their answers. In each study 15% to 27% of subjects said they remembered seeing items they had only read about. In another study subjects were asked to identify the source of misleading items they had seen in slides or read in misleading questions. Subjects were more likely to say they had seen in slides something they read about in the questions than they were to confuse information from two nearly identical sets of slides. Recent work shows that, not only is it possible to distort memory for events, it is possible to implant an entire memory for something that never happened. The evidence is now clear that we can become mentally tricked into making large as well as small changes in the way we recall the past. 相似文献
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Discrimination of methadone and cocaine by pigeons without explicit discrimination training. 下载免费PDF全文
D W Schaal M P McDonald M A Miller M P Reilly 《Journal of the experimental analysis of behavior》1996,66(2):193-203
Pigeons were trained to peck a key on a variable-interval 2-min schedule of food reinforcement. Prior to each session, either 2.0 mg/kg methadone (n = 3), 3.0 mg/kg cocaine (n = 4), or 5.6 mg/kg cocaine (n = 2) was administered. When each pigeon's rate of pecking was stable, a range of doses of the training drug and saline were administered prior to 20-min extinction sessions separated by at least four training sessions. Rate of pecking during these extinction tests was generally an increasing function of dose, with the lowest rates obtained following saline and low doses and the highest rates obtained following doses near the training doses. Dose functions from pigeons trained with 5.6 mg/kg cocaine were steeper than those from pigeons trained with 3.0 mg/kg cocaine. Pigeons trained with methadone or 3.0 mg/kg cocaine were then given discrimination training, in which food reinforcement followed drug administration and 20-min extinction sessions followed saline administration. Rates of pecking under these conditions quickly diverged until near-zero rates were obtained following saline and high rates were obtained following drug. Discrimination training steepened dose functions for the training drugs, and the effects of several other substituted drugs depended on the pharmacology of the training drug. The pigeons trained with 5.6 mg/kg cocaine were tested with d-amphetamine, methadone, and morphine prior to discrimination training. d-Amphetamine increased rates dose dependently, and methadone and morphine did not. The results suggest that discriminative control by methadone and cocaine was established without explicit discrimination training. 相似文献