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961.
Event-Related Potentials were recorded over occipital and parietal scalp from left- and right-handed adults presented with a language and a non-language visual stimulus using a divided field, "oddball" paradigm. The major finding of interest was that the P300 component was larger over the left than the right hemisphere of the right-handers when the language stimulus was presented to the left hemisphere; there were no hemispheric differences for the left-handers, regardless of field of presentation. These results are discussed in the context of developing noninvasive measures to lateralize language function.  相似文献   
962.
Long-term effects of cerebellar pathology on cognitive functions   总被引:3,自引:0,他引:3  
Twelve patients with circumscribed chronic neocerebellar lesions but without CT-evidence of forebrain damage (other than the effects of shunting) were investigated for deficits of cognitive functions. Two different mechanisms were considered as possible causes of cognitive impairment: (1) Damage to the dentato-thalamo-cortical projection leading to impairments of cortical functions, and (2) prolonged intracranial pressure resulting in diffuse forebrain damage and subcortical dementia. Patients with lesions in the left neocerebellum showed deficits in cognitive operations in three dimensional space, consistent with the right forebrain dominance for spatial functions. Prolonged intracranial pressure, on the other hand, resulted in a mild overall cognitive impairment.  相似文献   
963.
In addition to posing a risk for coronary heart disease (CHD), Type A behavior has been suggested as a risk factor for non-CHD illness. Past evidence, however, has relied chiefly on retrospective studies of self-reported illness that failed to control for the potentially confounding effects of negative affectivity. The present investigation was an 18-month prospective study of Type A behavior and medical records of illness in which chronic negative affectivity was also assessed. Negative affectivity was associated with retrospective self-reported illness, but only Type A, as measured by the Jenkins Activity Survey (JAS) and the Framingham Type A Scale (FTAS), predicted medical records of subsequent illness severity and number of illness-related medical visits. Controlling for negative affectivity did not reduce these significant relationships. It was concluded that persons scoring high on the JAS or the FTAS may be a greater risk of minor illness when objective measures of illness are assessed over a period of 1 year or more. Alternative explanations and future directions for research are discussed.  相似文献   
964.
Summary Young and elderly adults acquired route information from a sequence of slides depicting a walk through an actual environment. The accuracy of their distance knowledge after viewing the slides was compared for a normal presentation and a presentation with temporospatial discontinuity. No differences between age groups were noted under normal presentation conditions, but young adults were more accurate under conditions of temporospatial discontinuity. Results were interpreted in terms of an age-related decrement in the operational capacity of working memory. They were also viewed as supportive of a constructivist-representational theory of spatial learning.This research was conducted while the senior author served as Principal Investigator for National Institute on Aging Grant No. 1 ROI AG05169, Aging and Spatial Cognition, sponsored by the National Institutes of Health, Bethesda, MD, USA  相似文献   
965.
Summary In the literature two different views with regard to the time course of activation of recognition units —hypothetical entities that represent identity information —are proposed. Both views are derived from a restricted set of phenomena in visual perception. The first view gets its intuitions from phenomena such as those summarized by Bloch's law; these phenomena show integration or summation of activation over time. This grow-and-grow view assumes that recognition units accumulate activation gradually over times The second view finds its inspiration in phenomena such as Mach-bands and simultaneous contrast; these phenomena show inhibition or steady-state suppression over time. This grow-and-shrink view assumes that the activation levels increase fast initially and then start to decrease.The perception literature strongly suggests that it may be light intensity that determines whether mainly integration (and phenomena such as Bloch's law) or inhibition (and phenomena such as Mach-bands) is obtained. So it is also likely that both information-processing views apply only to a limited range of intensity conditions; the grow-and-grow view to conditions of low-flight intensities, and the grow-and-shrink view to conditions of intermediate-and high-light intensities.It is argued that, to arrive at a complete view, a visual phenomenon that applies to the complete range of light intensities should be taken as a background for generating hypotheses about time courses in visual-information processing. The Broca-Sulzer effect is such a phenomenon. Starting from this phenomenon a simple, synthesizing, information-processing model is derived that is compatible with both the grow-and-grow view and the grow-andshrink view. It is shown that, besides the relevant temporal properties, this model also produces the appropriate spatial properties.  相似文献   
966.
Two experiments were performed to assess the accuracy and precision with which adults perceive absolute egocentric distances to visible targets and coordinate their actions with them when walking without vision. In experiment 1 subjects stood in a large open field and attempted to judge the midpoint of self-to-target distances of between 4 and 24 m. In experiment 2 both highly practiced and unpracticed subjects stood in the same open field, viewed the same targets, and attempted to walk to them without vision or other environmental feedback under three conditions designed to assess the effects on accuracy of time-based memory decay and of walking at an unusually rapid pace. In experiment 1 the visual judgments were quite accurate and showed no systematic constant error. The small variable errors were linearly related to target distance. In experiment 2 the briskly paced walks were accurate, showing no systematic constant error, and the small, variable errors were a linear function of target distance and averaged about 8% of the target distance. Unlike Thomson's (1983) findings, there was not an abrupt increase in variable error at around 9 m, and no significant time-based effects were observed. The results demonstrate the accuracy of people's visual perception of absolute egocentric distances out to 24 m under open field conditions. The accuracy of people's walking without vision to previously seen targets shows that efferent and proprioceptive information about locomotion is closely calibrated to visually perceived distance. Sensitivity to the correlation of optical flow with efferent/proprioceptive information while walking with vision may provide the basis for this calibration when walking without vision.  相似文献   
967.
The kinds of messages teachers give students regarding the value of credentials in the job-getting package during a period of high youth unemployment are explored. The response made by students to the credentialling ideology promoted in schools, and their construction of the job-getting formula, are also described. The validity of the two versions of job-getting strategies is considered in the light of evidence provided by a number of empirical research projects. The superiority of student knowledge in this area is used to present a case for a critical and democratic education which appropriates and legitimises the student voice.  相似文献   
968.
This study was designed to examine the correlates of developmental psychological stress for 36 middle-aged professional men. Based on sex role convergence and role adjustment theories, two sets of predictor variables were hierarchically entered into a multiple regression equation with a third set of variables entered to control for individual stressors. Controlling for individual stressors, midlife stress outcome was found to be influenced only by role adjustment (R2=.3593). The sex role convergence cluster did not account for a significant increase in variance. Controlling for individual stressors, the best univariate predictors of stress outcome associated with the midlife transition were (a) the quality of the parent-adolescent relationship and (b) marital satisfaction.  相似文献   
969.
Three different kinds of termination are described and discussed. In combined therapy the group can help to resolve and clarify the meanings of moves to terminate therapy. The role of the therapist's countertransferences in this stage of the work is important to consider, and here, too, the group is an important part of the work. The author sees termination as an important part of the treatment process. In combined therapy it may be more complex but it also allows for a fuller exploration of the relevant issues.  相似文献   
970.
Spouse abuse is examined from the perspective of attribution theory. Aggressors are seen as attributing their violent behavior to external causes, whether by projecting their negative traits onto their spouses or by finding excuses which blame temporary environmental factors. In contrast, victims often attribute the abuse to defects within themselves or situational factors affecting their spouses. The attribution process seems affected by the frequency, intensity and duration of the abuse, with temporal factors playing an important role in the woman's internalizing style. Furthermore, inadequate early coping efforts play a powerful role in establishing cognitive-perceptual patterns that serve to perpetuate the abuse.  相似文献   
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