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231.
On the basis of the hypothesis of misapplied constancy scaling, the perception of an abstract horizontal-vertical illusion figure embedded in photographs of natural scenes with depth cues is investigated. The effect is compared with that of a figure on photographs containing no depth information and with a figure on a neutral surface. It is shown that the magnitude of the illusion in the perspective scenes is greater than in the other two conditions. The results are considered compatible with a constancy theory of the illusion. Finally, the evidence for misapplied constancy scaling in the horizontal-vertical illusion in relation to a retinal theory is discussed.  相似文献   
232.
233.
Distributions of reinforcers between two components of multiple variable-interval schedules were varied over a number of conditions. Sensitivity to reinforcement, measured by the exponent of the power function relating ratios of responses in the two components to ratios of reinforcers obtained in the components, did not differ between conditions with 15-s or 60-s component durations. The failure to demonstrate the “short-component effect,” where sensitivity is high for short components, was consistent with reanalysis of previous data. With 60-s components, sensitivity to reinforcement decreased systematically with time since component alternation, and was higher in the first 15-s subinterval of the 60-s component than for the component whose total duration was 15 s. Varying component duration and sampling behavior at different times since component transition may not be equivalent ways of examining the effects of average temporal distance between components.  相似文献   
234.
The present experiments studied a three-event delayed sequence-discrimination (DSD) task: one arrangement (order) of two stimuli (red and yellow overhead lights) taken three in succession (e.g., red, yellow, red) was the positive sequence and the remaining seven arrangements were the negative sequences for responding and reward during the subsequent test stimulus. In Experiment 1, the final stimulus (recency) and the order of stimuli in the positive sequence controlled acquisition of discrimination. In Experiment 2, increasing the duration of memory intervals between stimuli reduced the discriminability of those negative sequences identical to the positive sequence after the delay. Three-event DSD performance in Experiments 1 and 2 was similar to two-event DSD performance in comparable published experiments. Models developed to explain pigeon performance in two-event DSD were extended to the three-event task. Results from both two- and three-event versions of the DSD task falsified a noncumulative model and several cumulative integration models (i.e., adding, averging, and some multiplying models), but corroborated one cumulative, multiplying model.  相似文献   
235.
The following survey is intended to demonstrate and discuss some principle problems of biomagnetism and the application in clinical fields. The development of special technical parameters especially by the SQUID method is initiating new possibilities of research and completing the neurobiologically determinated basis and conditions of neuropsychiatric disorders. The Magnetoencephalography (MEG) will be represent an important role of a new functional diagnostic method.  相似文献   
236.
We present four cases of Prader-Willi syndrome. Two of them have an abnormality of a chromosome 15, the other both show different chromosomal abnormalities. Translocations or deletions were found recently in the bands 15q11/12 in about 60% of the cases of Prader-Willi syndrome. The consequences for diagnosis, symptomatology and genetic counselling of the syndrome are discussed.  相似文献   
237.
The cross-correlation method was used to measure interhemisphere phase differences over four areas of the brain in 22 healthy children aged between 7 and 10 years. Apart from defining normal values, the authors describe age-dependent characteristics and changes that take place as a result of mental stress.  相似文献   
238.
The foot is a highly cathected appendage that is commonly singled out as the brunt of humorous or derisive remarks, as if it embodies repugnance and disgust. Attitudes toward the foot are overdetermined, bearing the imprint of man's early linguistic patterns and individual dynamics. This article suggests that feet are symbolic because they bear the feelings derived from earlier separations, good and bad object representations, collective memories, and genital representations. The foot's role as symbol of both the male and female genitals, repository of badness, symbol of passivity, initiator of movement, and site of self-mutilation have been briefly reviewed. As Fats Waller rhapsodizes that the "feet's too big," he finds a convenient way to displace his symbiotic and erotic anxieties vis-à-vis women. Similarly, patients who come for psychiatric treatment and psychotherapy frequently make references to their feet or use them in specific ways. An understanding of this type of communication can often provide insight into individual dynamics and enhance treatment. The weight placed on these communications depends, of course, on the vicissitudes of the previous therapeutic work as well as on the particular problems of the patient.  相似文献   
239.
Gender differences across age in motor performance a meta-analysis   总被引:3,自引:0,他引:3  
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240.
Recent research on social cognition suggests that lifelike visual and vocal information about a person may strongly mediate the impact of prior social categorical knowledge on social judgements. Other research, however, on the contribution of visual cues to impression formation, suggests that they have relatively little impact. This study sought to resolve these conflicting findings by examining the effect of visual cues on social judgements when subjects possess prior social categorical knowledge varying in salience to the experimental task. Videotaped target interviews were monitored by observers in either sound and vision or sound only, and measures were taken of the targets' perceived personality, their ‘actual’ and ‘predicted’ social performance, and social acceptance by observers. Whilst salience of categorization strongly influenced the quality of judgements, visual cues had little if any effect. However, visual cues strongly influenced subjects' confidence in all three sets of judgements, sound and vision subjects being consistently more confident than their sound only counterparts. The findings are discussed in relation to previous research in both social cognition and visual cues.  相似文献   
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