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71.
The effects of dopaminergic depletion of the nucleus accumbens was tested in various behavioral tasks such as alternation, spatial discrimination, and reversal learning, and in an extinction paradigm in a T maze. Animals with lesions showed impairment of spontaneous alternation behavior, disturbances in the acquisition of spatial discrimination, and great difficulty in reversing previously learned habits. In the extinction phase, experimental animals are unable to adjust their behavior, and continue to choose the previously reinforced arm of the T maze. It is suggested that the nucleus accumbens plays an important role in the transition of motivation into action, and that dopamine has a facilitatory influence on the mediation of these processes.  相似文献   
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An attempt was made to test the hypothesis that the Egocentricity Index (Exner, 1974), a ratio which incorporates pair and reflection responses, is related to self-esteem. Sixty criminal defendants referred for psychiatric evaluation were routinely administered the Rorschach. After all other testing was completed the subjects were asked to complete the Coopersmith Self-esteem Inventory. Results found no significant relationships between the Egocentricity Index and self-esteem as measured by the Coopersmith. It was recommended that the Egocentricity Index not be used as a measure of self-esteem until research evidence to support its use in this manner is provided.  相似文献   
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Gender differences across age in motor performance a meta-analysis   总被引:3,自引:0,他引:3  
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Thomas R. Alley 《Synthese》1985,65(3):411-444
The concept of an ecological niche (econiche) has been used in a variety of ways, some of which are incompatible with a relational or functional interpretation of the term. This essay seeks to standardize usage by limiting the concept to functional relations between organisms and their surroundings, and to revise the concept to include epistemic relations. For most organisms, epistemics are a vital aspect of their functional relationships to their surroundings and, hence, a major determinant of their econiche. Rejecting the traditional dualism of organism and environment, an econiche is defined as the reciprocal (dual) of a functionally specified class of organisms (FSTU). From this perspective, an econiche necessarily implies a certain type of organism, and a class of functionally similar organisms implies a special econiche.The econiche concept is also discussed in relation to other ecological terms that reflect the distributional patterns of organisms, such as habitat, and the concept of an empty niche is criticized.Special thanks are due to Michael Turvery for his part in many stimulating discussions of some of the problems and concepts addressed in this paper. I am also grateful to him and to Claudia Carello, Tim Johnston, Bill Mace, Bernard Patten, Ed Reed, Robert E. Shaw, Bill Warren, and an anonymous reviewer for their comments on earlier drafts of this paper.  相似文献   
78.
In this study, the relationship between two commonly used measures of social competency, peer ratings of perceived status and adult ratings of assertiveness, were examined. In Phase I, high and low sociometric status children were videotaped responding to a series of role-play scenes; performance on these scenes was then rated retrospectively by adults for overall assertiveness. In Phase II, a second group of children who were unfamiliar with the videotaped children observed the taped scenes and provided ratings of likability, intelligence, working together, and attractiveness. In general, results revealed that children and adults differed in their ratings of the videotaped children. Further, boys used different cues in their ratings than did girls. More specifically, the sociometric status of girls was related to perceived attractiveness, whereas the sociometric status of boys was more closely related to perceived intelligence. Such findings suggest that children and adults look for and use different cues in their judgments. Given these differences, it is concluded that child and adult ratings should not be used interchangeably in the assessment of, and evaluation of, social competency in children.Portions of this research were supported by a grant from the Virginia Department of Criminal Justice Services.  相似文献   
79.
Work values and key influencers of a sample of black male and female adolescents were examined. Results indicated that boys and girls valued both the intrinsic and extrinsic rewards of work; however, girls reported slighter stronger extrinsic values than did boys. In addition, the sexes reported differences in the importance of specific work values such as "making lots of money," and "doing important things." When naming a key influencer, respondents tended to cite a same-sex and race individual. Sex of one's key influencer was related to certain work values, with subjects reporting a male key influencer valuing "trying out one's own ideas" and "having a secure future" more than those reporting a female key influencer. The interaction of sex of subject and sex of key influencer was significant on one of the work value outcomes. Implications of these findings are considered.  相似文献   
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In 1985 we published a meta-analysis of gender differences across age in motor performance in Psychological Bulletin, but it did not include an indexing of each motor task to the references from which it was obtained. This paper provides a table listing the 20 motor tasks and the references from which data for each task were taken. The range of tasks was from fundamental movements (e.g., catching, jumping, running, throwing) to motor fitness (e.g., agility, arm hang, balance, grip strength) to perceptual-motor abilities (e.g., anticipation timing, fine eye-motor coordination, pursuit-rotor tracking, reaction time). The arm hang was represented in the fewest papers (n = 2) while the dash and long jump were most frequently referenced (n = 21).  相似文献   
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