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The purpose of this study was to determine the effects of Type A behavior and family history of hypertension on cardiovascular reactivity to mental stress in a group of employed black women. Measures of heart rate and of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken at rest, during a mental arithmetic task, and during the Type A Structured Interview (SI). Results indicated that the Type A behavior pattern was associated with SBP and DBP hyperresponsivity during the SI but not during mental arithmetic. Additionally, certain speech components of the Type A pattern, as well as features of the potential-for-hostility component, were also related to cardiovascular responses during the SI. Family history of hypertension did not influence the cardiovascular parameters either alone or in combination with Type A behavior. The results suggest that many of the cardiovascular response characteristics of the Type A pattern that have been observed in predominantly white samples also hold true for blacks. Replication of these findings with other subgroups of blacks, such as young females and middle-aged males, will help document the generality of these findings within the black population.  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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A comparison of two measures of egocentrism   总被引:1,自引:0,他引:1  
This study examined the relationship between two prominent measures of egocentrism, Enright's Adolescent Egocentrism Scale (AES) and Elkind's Imaginary Audience Scale (IAS), in a sample of 458 adolescents, between 10 and 15 years old. Both correlational and factor analyses indicated that the two measures assess distinctly different phenomena. As predicted, IAS scores were correlated with self-reported levels of shyness, nervousness, and social skills. These results provide partial evidence for the validity of the IAS as a measure of self-consciousness, though not necessarily egocentrism per se. The validity of the AES was not examined.  相似文献   
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An experiment was conducted to examine the effects of medical diagnostic-test results on illness appraisal and the recall of symptoms and behavior. Subjects were tested for a fictitious enzyme deficiency and were told either that the test result was positive (deficiency present) or that it was negative (deficiency absent). In addition, some of the subjects were told the test was accurate 95% of the time and others were told it was accurate 75% of the time. As predicted, subjects judged the enzyme deficiency as less serious and more prevalent when presented with positive test results. Subjects with positive test results also recalled more behaviors that had been labeled as risk factors. Although positive test subjects tended to report more deficiency-related symptoms, diagnosis did not affect the free recall of general symptoms. In addition, information concerning the reliability of the diagnostic test had no effect on judgments or recall but did affect information seeking. Subjects with positive test results were less likely to request a definitive follow-up test when their results were unreliable. The results are interpreted as evidence for independent confirmatory search and denial processes following medical diagnosis.  相似文献   
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This study examined attitudes among 290 residents of three villages in South-West England toward proposals to build a nuclear power station nearby. Respondents were split into four groups according to whether they were neutral or in favor of a new power station either locally or elsewhere in the UK (Group PN), against one locally but neutral or pro elsewhere (LO), or moderately (MO) or extremely (XO) against a new power station both locally and elsewhere. The perceived impact of a nuclear power station on local life was assessed by 30 items. The PN group expected most benefit or least damage on all 30 items. On a majority of items the mean ratings of the LO group resembled those of the XO's more than did those of the MO's. A stepwise discriminant analysis yielded two interpretable functions. The first reflected a trend over the groups in the order PN-LO-MO-XO and was marked particularly by concern with impact on personal peace of mind. The second fuction discriminated the LO's from the other groups, suggesting that they were relatively less concerned with specifically nuclear risks, but more concerned with environmental conservation.  相似文献   
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