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931.
The true receptive field of more than 90% of neurons in the middle temporal visual area (MT) extends well beyond the classical receptive field (crf), as mapped with conventional bar or spot stimuli, and includes a surrounding region that is 50 to 100 times the area of the crf. These extensive surrounds are demonstrated by simultaneously stimulating the crf and the surround with moving stimuli. The surrounds commonly have directional and velocity-selective influences that are antagonistic to the response from the crf. The crfs of MT neurons are organized in a topographic representation of the visual field. Thus MT neurons are embedded in an orderly visuotopic array, but are capable of integrating local stimulus conditions within a global context. The extensive surrounds of MT neurons may be involved in figure-ground discrimination, preattentive vision, perceptual constancies, and depth perception through motion cues.  相似文献   
932.
This study describes the development of the Attitudes Toward Women Scale for Adolescents (AWSA), an instrument based on the short form of the Spence-Helmreich Attitudes Toward Women Scale (AWS). The AWSA has been tested in four samples of adolescents. Internal consistency estimates and test-retest stability indicated high reliability. Hypotheses formulated to test the construct validity of the scale were largely supported. AWSA permits the examination of how boys' and girls' attitudes toward women influence the life paths that adolescent girls begin to pursue.This research was supported by grants to A. Petersen from the Spencer Foundation, the National Institute of Mental health (MH 30252/38142), and the Judith Baskin Offer Fund.  相似文献   
933.
The purpose of this study was to examine the attitudes of a general population toward female participation in sports and to replicate a previous study. The two areas investigated were (1) the perception of enhancement or detraction of femininity by girls' participation in athletics, and (2) whether different sports elicited different attitudes towards female participation in athletics. A town in Iowa was sampled. The results indicated that, in general, participation in sports neither detracted from nor enhanced femininity. Furthermore, most of the people wanted their daughters to play basketball, even though it neither detracted from nor enhanced femininity. The data suggest that traditional, rigid sex-role stereotypes were transcended and the opportunity set was dominant.This study was partially funded by a grant from the University of Iowa Graduate School. Appreciation is expressed to Dr. Eldon Snyder for graciously sharing his instrument and recent work.  相似文献   
934.
A case-study of gay identity development is presented based on Kelly's personal construct theory. The subject is a married man in his early thirties. Repertory grid technique is used to investigate the subject's construing of his relationships with gay men, and Kelly's account of emotion in terms of constructs of transition is used in analysing the emotional dimensions of the subject's experience. Three dimensions of interpersonal construing emerged from the grid analysis: emotional impact, negative affect and friendship. Five aspects of the subject's emotional experience are discussed: aggression, threat, anxiety, hostility and guilt. Some implications of the study for counselling are outlined, its limitations noted, and possible avenues for further research identified. It is argued that the study serves to illustrate the value of Kelly's perspective in understanding the interpersonal and emotional dimensions of gay identity development.  相似文献   
935.
The publication in 1973 of Student Counselling in Practice signalled a new phase in the development of both careers and counselling services in the tertiary sector. The emergence of the professional careers adviser in higher education is described alongside the key role of the Association of Graduate Careers Advisory Services. The gradual professionalisation of student counselling is shown to have taken a different form, as a result of the policies of the Association for Student Counselling with its insistence on role definition and the accreditation of practitioners. Developments in further education are briefly reviewed, and a final section considers the present situation and possible future trends.  相似文献   
936.
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   
937.
To test the generality, across modality and across species, of a bidirectional effect of photic stimulation in infant rats found in previous experiments, two experiments examined the effects on heart rate (HR) of onset and offset of auditory stimulation in rats and of photic stimulation in guinea pigs. Experiment 1 demonstrated a unidirectional, decelerative response in rats 17 and 21 days of age to the onset and offset of a 1-kHz tone, at both low (80 dB) and high (100 dB) intensity levels and at 14 days to the onset of the high-intensity tone. Experiment 2 demonstrated that infant guinea pigs, which unlike infant rats are precocial and not nocturnal, responded to the offset but not to the onset of light, and that this response was decelerative. These results indicated a lack of generality of the bidirectional HR effect, and were discussed in terms of the orienting/defensive reflex distinction.  相似文献   
938.
During 46 consecutive days the daily food intake and weight were recorded in 16 male Wistar rats. On Days 31-45 one mouse was presented each rat daily. Before any experience with mice (Days 0-27) the mousekiller rats, compared with the nonkiller rats, regulated their individual food intake more closely to their homeostatic equilibria, corrected for the linear trend. This result indicates a functional difference in food intake regulation between mousekiller rats and nonkiller rats prior to any experience with mice. However, no difference in the mean food intake was found between the mousekiller and the nonkiller rats.  相似文献   
939.
Individual differences in attribution have been little researched. Beliefs about locus of control have been taken to be stable and important differences between people. They may provide some of the background assumptions on which people base their explanations of actions, especially insofar as these explanations imply that the cause of an action was within the agent or his environment, and that the action was or was not under the agent's control. Respondents were therefore asked to fill in Rotter and Levenson locus of control questionnaires and to provide explanations or ask questions about several actions. It was hypothesized that internals would be inclined to go for explanations which were personal and implied high control, while externals would not. However, what emerged was the paradoxical finding that internals provided explanations which implied that the causes of the actions lay outside the agent, while externals provided ones which implied that the causes lay within. This result is discussed in terms of the difference between actions and outcomes, and the possibility that an important difference between people may be in the rigidity and simplicity of their beliefs about causality.  相似文献   
940.
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