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211.
Contrast sensitivity was measured for 12 healthy young males while sober, after ingestion of an alcohol placebo, and after ingestion of alcohol (95% grain alcohol; mean estimated blood alcohol level = .088%). Observations were made for both stationary gratings and gratings that traveled through a circular path and required pursuit eye movements. The significant alcohol-related reduction in contrast sensitivity was 2.6 times greater for moving (.29-log-unit reduction) than for stationary gratings (.11-log-unit reduction). The loss in contrast sensitivity for the moving gratings of high spatial frequency (12 cpd) was particularly severe (.37 log unit). Estimated blood alcohol level was correlated with the loss in contrast sensitivity for moving gratings (r = .61), but not with the loss for stationary gratings. Estimated blood alcohol level was strongly correlated with the difference between the loss in contrast sensitivity to moving and stationary gratings (r = .75). These results are consistent with reports that alcohol consumption degrades the ability to make pursuit eye movements. Subjects’ perceived intoxication level was not a reliable predictor of any index of visual performance.  相似文献   
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It is not known whether nominally different olfactory tests actually measure dissimilar perceptual attributes. In this study, we administered nine olfactory tests, including tests of odor identification, discrimination, detection, memory, and suprathreshold intensity and pleasantness perception, to 97 healthy subjects. Aprincipal components analysis performed on the intercorrelation matrix revealed four meaningful components. The first was comprised of strong primary loadings from most of the olfactory test measures, whereas the second was comprised of primary loadings from intensity ratings given to a set of suprathreshold odorant concentrations. The third and fourth components had primary loadings that reflected, respectively, mean suprathreshold pleasantness ratings and a response bias measure derived from a yes/no odor identification signal detection task. In an effort to adjust for potential confounding influences of age, gender, smoking, and years of schooling on the component structure, a matrix of residuals from a multiple regression analysis, which included these variables, was also analyzed. A similar component pattern emerged. Overall, these findings suggest, in healthy subjects spanning a wide age range, that (1) a number of nominally distinct tests of olfactory function are measuring a common source of variance, and (2) some suprathreshold odor intensity and pleasantness rating tests may be measuring sources of variance different from this common source.  相似文献   
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Recent investigations have explored dispositional optimism as a determinant of various health-related behaviors, though such research has been infrequently conducted in populations where pessimism would be expected to be prevalent. The present study examines optimism and unsafe sexual behavior in 230 sexually active inner-city minority adolescents. Findings suggest that dispositional optimism is a protective factor regarding adolescents' intentions to avoid engaging in unsafe sex. Further, the benefits of optimism appear to be explained by those who are more optimistic having higher levels of perceived condom use self-efficacy and stronger negative expectancies toward unsafe sex. Future interventions may need to address optimism in concert with behavioral-specific determinants to increase the probability of reducing unsafe sexual behavior in high-risk populations.  相似文献   
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Predicting Adolescents' Initiation of Intercourse and Contraceptive Use   总被引:1,自引:0,他引:1  
This paper examines whether variables consistent with problem behavior theory predict grade of onset of first intercourse and adoption of effective contraception. A total sample of 3,419 Wisconsin adolescents in Grades 7, 9, and 11 participated in a survey of health-related behaviors administered 3 times across a 6-year period. The sample is 87% White. Multiple regression methods generated different models for onset of sexual intercourse vs. contraceptive adoption. Consistent with problem behavior theory, sexual onset is predicted by the adolescent's behavioral system, perceived peer substance use/abuse, importance of friends, and extent to which the adolescent felt harried and believed it was okay to break laws. Contraceptive adoption is predicted by family structure, socioeconomic variables, and self-esteem. Age and gender model differences emerged.  相似文献   
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The aim of this paper is to demonstrate how object relations theory can be used to understand and regulate interpersonal conflict in group psychotherapy. Such concepts as projective identification, intersubjectivity and the analytic third are used to describe how conflict emerges in group psychotherapy and how it can be worked through. Case material is also provided to illustrate concepts and techniques in promoting a group's transition from a paranoid/schizoid to a depressive position. Positive aspects of the concept of projective identification are discussed including its use as a form of communication, a method of reducing anxiety and reintegrating previously dangerous and threatening aspects of the self.The paper was funded by Evan F. Lilly Memorial Trust Grant PV 13,067.  相似文献   
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