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871.
Fetal brain tissue from the occipital or the frontal cortex was implanted into the damaged occipital cortex of adult rats. The animals receiving grafts of embryonic frontal cortex showed partial restoration of brightness discrimination while recipients given homologous implants of occipital cortex were as impaired as those animals with lesions alone. Neither frontal nor occipital grafts aided in the performance of a pattern discrimination problem; both groups of brain-damaged animals were unable to learn the task. Nonetheless, both groups of animals had viable and enlarged grafts with similar neuronal and glial profiles.  相似文献   
872.
The present study attempted to identify behavioral skills associated with global perceptions of communication competence and to determine if the relationship between competence and skills varies as a function of perceptual locus. Fifteen dyadic conversations were videotaped. Each interactant rated self and partner and was rated by four observers who viewed each tape. Results indicated that subjects' perceptions of their partners' skills accounted for 87% of the variance in subjects' ratings of partners' competence and 80% of the variance in subjects'self-perceived confirmation. Observers' ratings of subjects' skills predicted 83% of the variance in observers' ratings of subjects' competence. Observers'ratings of subjects'skills were unrelated to subjects' self-rated competence.  相似文献   
873.
The truncated nuclear family is defined: it is the garden-variety family pathology found. The critical role of polarized continuity and discontinuity values in producing the truncated nuclear family is discussed. There is a brief review of factors in American society which, over the decades since the Second World War, have evolved the nuclear family as a dominant family unit, and of how those and other factors in society have produced the large numbers of truncated nuclear families seen in clinics, particularly in the past decade. Family therapy is the treatment of choice for the truncated nuclear family, provided there is a readiness of the family to undertake the stress of therapy.Dr. Zuk is family therapy consultant to agencies in New Orleans and elsewhere, and clinical professor (psychology) in the Department of Psychiatry and Neurology at Tulane University Medical School.This paper is a chapter in the forthcoming 2nd edition ofProcess and Practice in Family Therapy, to be published by Human Sciences Press of New York City in 1985.  相似文献   
874.
Considering the findings that schizophrenics have been found to show relatively slow reaction times (RTs), and often do not benefit from ordinarily helpful information (e.g. a warning signal), the present study investigated the relationship between these variables and psychoticism (P). One hundred and three male Ss were administered a questionnaire which provides a measure of P. In addition, all Ss were tested on an RT task under unsignalled (i.e. no warning signal) and signalled conditions. The results showed that the expected improvement in reaction speed with a warning signal was of a lesser magnitude for those high on P. Furthermore, the difference was due to the faster RTs for high P scorers in the unsignalled condition. The data suggest that high P scorers are like schizophrenics in that they show less benefit from a warning signal, but are dissimilar in terms of reaction speed in an unsignalled task.  相似文献   
875.
876.
Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.  相似文献   
877.
Expectancy theory concepts were used to predict (a) the attractiveness of, (b) the amount of effort directed toward entering, and (c) the eventual choice of a job in relatively big and small work organizations. It was found, among a group of graduating seniors from a technical college, that antecedent perceptions regarding organizational size (expectancy, valence, instrumentality) were significantly related to the relative attractiveness of different-sized organizations and the number of job interviews taken with relatively big and small companies. In addition, economically tied extrinsic outcomes were seen as more readily attainable in big organizations, whereas certain intrinsic outcomes were perceived to be more easily obtained in small organizations.  相似文献   
878.
Lane has argued that kantowitz and Knight incorrectly predicted an interaction between primary and secondary task difficulty for the variable-allocation model of attention. It is shown that such an interaction is indeed obtained if task-performance difficulty is defined in terms of capacity and only reasonable transformations of data are permitted. This interaction holds for any set of monotonic resource operating characteristics.  相似文献   
879.
The study examined the effects of providing six levels of research information to 270 classroom subjects on the data obtained from three different cognitive tasks. The effects of the three tasks on the subjects' academic self-concepts were also investigated. No significant differences were found among the six levels of information for each of the three tasks. On the logical task a significant linear relationship was found supporting previous research which indicates that the more information that is given to research subjects, the more negative the results. There were no significant differences on self-concept scores across the three tasks used. Overall, the implementation of ethical principles had little effect on data collected in classroom settings, indicating support for implementation. This data did indicate, however, that providing more information than required under the ethical principles can result in data bias on a specific task.  相似文献   
880.
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