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871.
When discriminated interresponse-time (IRT) procedures have been used to assess preference relations among temporally extended operants, deviations from matching have been obtained. Using a yoked-control procedure, the present study found that key pecking in a discriminated IRT procedure has two sources of strength--that arising from the response-reinforcer contingency that is explicitly arranged, and that arising from a stimulus-reinforcer contingency that is a by-product of the explicitly arranged contingency. The key pecking of all lead birds, and that of 3 of the 4 birds exposed to a yoked autoshaping procedure, was controlled by the keylight that signaled the lead birds' criterion IRTs. Because stimulus control of key pecking by the keylight, whether autoshaped or discriminative, fosters deviations from matching, the discriminated IRT procedure does not provide an appropriate basis for conclusions about preference relations among IRTs.  相似文献   
872.
Summary Soon after Wheatstone published his results obtained with the twelve earliest stereograms. Brewster disputed the result obtained with one of them. This stereogram consisted of a thick vertical line presented to one eye and a thin vertical and thick inclined line to the other. Wheatstone reported seeing depth with this figure but Brewster did not. We conducted three experiments to explore the possible reason for the disagreement. Experiment 1 indicated that the stereogram produces a variety of perceptions including the depth as reported by Wheatstone and the rivalry as reported by Brewster. Experiment 2 showed that Brewster's procedure of keeping the eyes fixed while viewing the stereogram reduces the proportion of subjects reporting depth. In Experiment 3, the top half and the bottom half of the stereogram were presented in different trials. The top of the stereogram that contains no conflicting cues produced reliable depth, but the bottom that does, did not. It is concluded that the difference in the procedures they used and the nature of the stimulus were responsible for the conflicting results.  相似文献   
873.
Some effects of color on naming and recognition of objects   总被引:1,自引:0,他引:1  
In this article, we investigated the role of color in the recognition and naming of everyday objects. In the first experiment we found that color pictures were named faster than black-and-white and that shape information did not facilitate color naming. Experiment 2 was carried out to determine at which stage of object processing the color facilitation occurred. We found that color had no effect on object recognition but did facilitate object naming, even when color was redundant for discrimination. This did not apply to naming abstract shapes. Experiment 3 replicated the findings of Experiment 2 using different objects and colors. The results showed that color could facilitate but not inhibit object naming and did not affect object recognition.  相似文献   
874.
Do alcoholic Korsakoff's syndrome patients acquire affective reactions?   总被引:1,自引:0,他引:1  
In this study we report two experiments that investigate the acquisition of affective reactions. In Experiment 1, unfamiliar melodies were played to Korsakoff's syndrome patients and alcoholic and nonalcoholic control subjects who were matched with them according to age and education. Following a retention interval of 5 min, subjects received a preference test on old and new melodies. Korsakoff's syndrome patients showed the same increase in preference for old melodies as a consequence of prior exposures as control subjects did, but their recognition of melodies was significantly impaired in comparison with controls. In Experiment 2, the same subjects saw photographs of two men. Fictional biographical information depicted one as a "good guy" and the other as a "bad guy." After a retention interval of approximately 20 days, Korsakoffs recalled virtually none of the biographical information; however, 78% preferred the good guy, and impression ratings were less favorable for the bad guy. Korsakoff patients developed preferences and impressions even though they did not have voluntary access to the information on which the preferences were based. However, their impression ratings were less extreme than those of controls. The pattern of results of the two studies is discussed in terms of Johnson's (1983) MEM model of memory.  相似文献   
875.
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   
876.
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   
877.
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   
878.
Young people's qualifications are strongly related to their occupational success. It is often assumed that this can be largely accounted for by employers' selection on the basis of attainment. A variety of attainment-related attitudes and behaviour among young people which may contribute to the relationship are examined. The findings suggest that qualifications subsume a variety of behavioural factors which have an important direct effect on young people's chances in the job market.  相似文献   
879.
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   
880.
Summary The method of fixed set (Uznadze, 1966) was applied to the size-weight illusion. After the repeated lifting of a small, heavy stimulus and a large, light one with both hands simultaneously, the size-weight illusion diminished. It increased after lifting a small, light stimulus and a large, heavy one. These changes in perception were explained as contrast effects caused by the sets which were fixed during the preceding lifts. The same method was applied to the weight-size illusion and the contrast effect was observed in some cases. The results of the application of the fixed-set method to the size-weight illusion and to the visual size perception were compared. All the results showed analogous patterns of conflicting states between the temporarily fixed set and the set that the subject prepares naturally for perception, such as the size-weight illusion. By way of conclusion, the size-weight illusion was assumed to be a kind of contrast effect in the light of Uznadze's theory of set.  相似文献   
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