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801.
802.
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   
803.
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   
804.
Gender differences across age in motor performance a meta-analysis   总被引:3,自引:0,他引:3  
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805.
Two perspectives on the nature of the social group and psychological group formation are discussed. The traditional social cohesion approach traces group formation to processes of interpersonal attraction, while the social identity approach defines the group in cognitive terms and considers identification, or self-categorization, to be the mechanism of psychological group formation. On the basis of an experiment by Turner, Sachdev and Hogg (1983) it is hypothesized that interpersonal attraction (positive or negative) is related to group formation only in so far as it enhances intergroup distinctiveness. This hypothesis is experimentally tested in a 2 × 3 (interpersonal liking/disliking per se versus no explicit categorization/random categorization/criterial categorization on the basis of affect) factorial design employing the ‘minimal group’ paradigm. People who like each other and were not explicitly categorized formed a group. This effect was enhanced by criterial categorization but disappeared when categorization was random. Although the results do not support the hypothesis, they are not explicable in social cohesion terms. A social identity explanation is furnished—attraction influences group formation by acting, under certain specifiable conditions, as a cognitive criterion for common category membership. This explanation is located in current theorizing and is proposed as part of a reconceptualization of the relationship between interpersonal attraction and group formation.  相似文献   
806.
Additional results from Rutte and Wilke's (1984) study are presented. In the context of a social dilemma situation two variables were manipulated: use and variance. Preference for various decision structures is the issue of the present paper. It appeared that a large majority structure and an unanimity structure were mast preferred. A small majority structure and a structure in which each decides for him/herself were intermediately preferred. Whereas a structure in which one person, a leader, decides for all was least preferred. Further analysis of these data suggested that only the latter two decision structures were influenced by the use and variance manipulations.  相似文献   
807.
Deficient processing theories of the spacing effect attribute poor recall of massed-repeated items to a failure to process one or both of the presentations fully. An implication of this approach is that anything that increases the probability that a repetition will receive full processing, or conversely, anything that decreases the probability that the item will be recognized as a repetition, should improve memorability of the item. The present set of experiments tested this prediction by manipulating the surface structure of repeated sentences. On the basis of previous research, it was assumed that memory for surface structure of sentences decays rapidly, and hence can contribute to initial identification of repetitions only at short spacings. Because this manipulation should hinder recognition of repetitions as repetitions, it was expected to induce full processing of massed repetitions, and thus facilitate recall of these items. This prediction was supported. When sentences were repeated verbatim (Experiment 1) or by the same speaker (Experiment 2), the typical spacing effect was obtained. However, when the surface structure or speaker changed at time of repetition, massed repetitions were recalled nearly as well (Experiment 1) or as well (Experiment 2) as their spaced counterparts.  相似文献   
808.
When a sentence with more than one clause is processed, words of the first clause become less available for recall or recognition once the clause boundary has been passed. One common interpretation of this observation is that the representation of a given word shifts from a predominantly surface form (e.g., phonological or lexical) to a semantic form, after the clause boundary. Two experiments that test that interpretation are reported. In the first experiment, two-clause spoken sentences were followed by spoken word or picture probes. Pictures were intended to provide a fast semantic match to probed words, but a slow surface match. Although response times exhibited a robust main effect of the clause position of the probe, no interaction with probe type was found. Similar results were obtained in a second experiment that compared pictures with written word probes. The faster response to picture than to word probes in the second experiment indicates that subjects did not covertly name the picture, but made a semantic match (as intended). These observations suggest the following reinterpretation of earlier sentence memory experiments: Words in the most recent clause of a sentence are more available than words in an earlier clause because their semantic representations are more active, not because their surface representations are more active.  相似文献   
809.
The intent of the study was to examine the effects of parental (mother and father) and child (gender and communicative status) status variables on the teaching strategies used by parents in a paper-folding task. The linguistic and nonverbal strategies of 120 parent-child groupings were analyzed during paper-folding tasks. Parents' strategies were coded according cognitive demand and directiveness. Results indicated that strategies varied as a function of children's communicative status. Parents were less directive and more demanding of nonhandicapped children compared to handicapped children. Parents' strategies seemed to be determined by children's ability to sustain discourse. Results are discussed in terms of Vygotsky's notion of the zone of proximal development.This research was partially supported by a grant from the U.S. Office of Education, Office of Special Education (Grant No. G007902000) to I. Sigel and A. McGillicuddy-DeLisi at Educational Testing Service, Princeton, and from the Biomedical Research Support Grant Program, Division of Research Resources, N.I.H. (Grant No. BRSG 507RR07025-17) to the first two authors. We acknowledge the helpful comments of two anonymous reviewers.  相似文献   
810.
This study examined two issues related to the use of nonprofessional counselors (n = 159) within the context of a diversion program for juvenile offenders. First, the relationship of the nonprofessionals' personality traits and general attitudes to client outcome was examined. No statistically significant correlations were observed. Second, the differential impact of various training and supervision factors was examined in terms of nonprofessional satisfaction, attitudes, and locus of control. Results suggested that training intensity, training content, and supervision setting may influence nonprofessionals' attitudes towards various social groups and their satisfaction with the nonprofessional experience.  相似文献   
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