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A group of 115 black male adolescents drawn from a clinically unselected birth cohort, half of whom were known to have had neurological soft signs at age 7, were examined at age 17 to determine the relation between soft signs and performance on standard tests of school achievement and sustained attention. Three signs measured at age 17-dysgraphesthesia, difficulties with rapid alternating movements (dysdiadochokinesis), and motor slowness—were related to lower concurrent and past IQ and to impaired performance on laboratory and paper-and-pencil measures of sustained attention. The relation between signs and the attentional measures remained significant after IQ was statistically controlled. The three age 17 soft signs as well as age 7 signs were related to impaired performance on standardized tests (age 17) of school achievement. Most of the relation between signs and school achievement could be accounted for by the variance signs shared with sustained attention. One sign, mirror movements, was unrelated to all other attentional and cognitive measures.The study was supported by center grant MH 306906 and research training grant 5 T32 MH 13043-13 from the National Institute of Mental Health, as well as by the City College and the City University Computing Centers. We thank Lillian Belmont and two reviewers for their critical comments on an earlier version of the paper. We dedicate this paper to the memory of Joseph Barmack.  相似文献   
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The Additive Factor Method assumes that task performance is the sum of sequential and independent processes. We studied the duration of the central processes (memory search and decision) and the motor decision process in hyperactive and learning-disabled children under socalled divided attention and S-R compatibility conditions. It was found that the learning-disabled were impaired in memory search and decision processes whereas hyperactives were impaired in the motor decision process.The authors wish to thank L. Leertouwer for making the drawings.  相似文献   
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Some properties are discussed of regular polygons that may result from angular homeostatic processes in stable orbit. To characterize these homeostatic polygons we need to discuss the winding number, the sidedness (integer, fractional and irrational), multiplicity, envelopes, and density. A regular (i.e., equilateral, equiangular) polygon may be closed in one revolution about its unique center, in multiple revolutions, or not at all. A homeostatic polygon can be generated only if all vertices are included in a single polygon, which occurs if and only if the number of vertices and the number of revolutions required to complete the polygon are relatively prime. For the homeostatic polygon to have a finite number of sides (without repeating itself) the angle subtended by any two successive vertices at the center must be a rational multiple of 2. Biological implications of these properties are illustrated.  相似文献   
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Contributions of clinical neuropsychology to the study of schizophrenia   总被引:4,自引:0,他引:4  
Clinical neuropsychological findings are examined with respect to competing hypotheses about localized neuropathology in schizophrenia. Two general models of structural and functional impairment are described. The first addresses deficits in cortical/subcortical processes concerned with arousal, attention, and higher cortical functions. The second addresses impairments in the balance of lateralized functions consistent with left hemisphere overactivation. Empirical data provide support for both models, and suggest that the explanatory power of these models may vary when they are applied to different subtypes of schizophrenia.  相似文献   
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In two studies, co-workers of persons with disabilities were taught to use coincidental training procedures while completing their own jobs. In Study 1, the effects of coincidental training on the salad-making skills of 3 trainees with mild and moderate mental retardation were evaluated. Coincidental training by co-workers resulted in improved accuracy of the salad-making skills of the trainees. In Study 2, trainees were also coincidentally taught to make quality-control checks of their salads. An alternating treatments and multiple baseline design indicated that the trainees more readily acquired the skills when taught to check the correctness of their work.  相似文献   
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Dobbins  Gregory H.  Stuart  Cecile  Pence  Earl C.  Sgro  Joseph A. 《Sex roles》1985,12(5-6):549-560
The present study examined the effects of the sex of the leader, the sex of the rater, and the temporal position of leader performance information on ratings of leader behavior. Male and female subjects listened to an audiotape of a male or female leader and then rated the leader's initiating structure and consideration behaviors. The position of the leader performance information was manipulated by describing the leader as successful before or after raters listened to the audiotape or not presenting raters with the performance information. Analyses indicated that the sex of the leader and/or sex of the rater biased ratings of initiating structure when the performance information was presented after the audiotape and when no leader performance information was presented. Consideration ratings were affected only by the position of the leader performance information. The results are interpreted within a cognitive/implicit sex theory framework. Implications for leadership research are also discussed.Portions of the data analyzed in this study were collected by the second author as part of a master's thesis directed by Joseph A. Sgro.  相似文献   
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ABSTRACT Many philosophers who wish to defend abortion, but who have become frustrated by the resistance of the personhood question to yield to any nonarbitrary solution welcomed Judith Thomson's 'A defense of abortion.'Thomson argues that abortion is sometimes justifiable even if the foetus is a person. In this paper I argue that Thomson's argument is a defense of abortion, rather than merely extraction without death, only because of the current state of medical technology. Once the technology is in place to extract foetuses while preserving their lives and to allow them to develop to full term outside the uterus, Thomson cannot defend the killing of the foetus. If she is right, however, a woman will still have the right to have a foetus extracted from her body. Finally, it is pointed out that the source of the problem with Thomson's argument is the major premise in most arguments for the permissibility of abortion: a woman's right to control her own body. If the defence of abortion is to entail a defence of the termination of the foetus, then this premise, understood as the right to remove an unwanted entity from one's body or the right to alter one's body as one wishes, simply will not do the trick.  相似文献   
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