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251.
The epsilon4 allele of the apolipoprotein E (APOE) gene is a known risk factor for Alzheimer's disease and may also affect cognitive performance in normal aging. Evidence of the presence and magnitude of epsilon4-related cognitive deficits was examined with a meta-analysis of the available literature. Thirty-eight studies were included, and cognitive performance was collapsed into 8 domains. Results indicated significant APOE-epsilon4 group differences for global cognitive functioning, episodic memory, and executive functioning, in favor of non-epsilon4 carriers. In addition, older age and APOE-epsilon4 heterozygosity was associated with smaller epsilon4-related impairments. The meta-analysis results suggest that APOE-epsilon4 genotype does affect cognitive performance in healthy aging, although the influence is relatively small and specific to certain domains of cognitive performance.  相似文献   
252.
Information processing is impaired when two tasks are performed concurrently. The interference between the tasks is commonly attributed to structural bottlenecks or strategic scheduling of information processing. The present experiment investigated the effects of time pressure for the second of two responses on information processing in overlapping tasks by recording the lateralized readiness potential (LRP). Time pressure shortened the latency of the second response by diminishing the time devoted to motoric processing. In addition, task interference decreased under time pressure, which is probably due to the relatively early availability of the central bottleneck stage rather than to increased overlap of central stages. The LRP also provided direct evidence for an additional bottleneck following response selection, possibly due to supramodal refractoriness of response initiation.  相似文献   
253.
Predictors of self-reported suicide attempts were studied cross-sectionally and prospectively in order to discern which variables may account for the gender difference in such reports. A representative sample of Norwegian students (N= 9,679) in grades 7-12 were followed from 1992 to 1994. More girls (10.4%) than boys (6.0%) reported a previous attempt and more girls (3.3%) than boys (1.9%) reported an attempt during the study period. The gender difference in previous suicide attempts was significantly reduced when depressed mood was controlled, and was no longer significant when disordered eating was included. There was no gender difference in future attempts when previous attempts, depressed mood, physical appearance, pubertal timing, and romantic involvement were controlled. Girls' higher level of risk factors may account for their higher level of self-reported nonfatal suicidal behavior.  相似文献   
254.
Past and future suicide attempt rates among gay, lesbian, and bisexual (GLB) young people were compared with those of heterosexual young people. A sample of Norwegian students (N = 2.924; grades 7-12) was followed in 3 data collection waves. Risk factors included previous suicide attempt,depressed mood, eating problems, conduct problems, early sexual debut, number of sexual partners, pubertal timing, self-concept, alcohol and drug use, atypical gender roles, loneliness, peer relations, social support, parental attachment, parental monitoring, and suicidal behavior among family and friends. When homosexual attraction, homosexual identity, and same-sex sexual behavior were entered to predict suicide attempt, only same-sex sexual behavior was significantly predictive. The increased odds could not be attributed to GLB students' greater exposure to risk factors for suicide attempt.  相似文献   
255.
256.
Two experiments, an off-line acceptability judgment study and an on-line self-paced reading experiment, were conducted to tackle the question of locality-based preferences in sentence processing. The material consisted of German verb-final sentences containing a relative clause that was either host adjacent or extraposed. While the off-line data seem to reflect locality based integration cost, the on-line data revealed a highly different picture. It is argued that, in the present constructions at least, locality is relevant for production rather than perception. In perception, heads can be anticipated through incremental integration of their arguments.  相似文献   
257.
The revival of republicanism was meant to challenge the hegemony of liberalism in contemporary political theory on the grounds that liberals show insufficient concern with institutional protection against political misrule. This article challenges this view by showing how neorepublicanism, particularly on Philip Pettit's formulation, demands no greater institutional protection than does political liberalism. By identifying neutrality between conceptions of the good as the constraint on institutional requirements that forces neorepublicanism into the liberal framework, the article shows that neutrality is what neorepublicans must jettison to offer a tenable critique of liberalism. Only then can neorepublicans ensure greater protection against misrule by demanding that citizens participate more actively in politics. They can then also criticize liberalism for failing to appreciate the importance of such protection.  相似文献   
258.
Saccade performance has been reported to be altered in Parkinson's disease (PD), however, with a large variability between studies as both motor and cognitive impairment interfere with oculomotor control. The aim of this study was to identify different patterns in saccade alterations in PD using a data-driven approach and to explore their relationship with cognitive phenotypes. Sixty-one participants with PD and 25 controls performed eye-tracking (horizontal and vertical prosaccades, antisaccades) and neuropsychological testing. Hierarchical cluster analysis was applied to the eye-tracking data to subsequently compare the clusters based on demographical, clinical and cognitive characteristics. The three identified clusters of saccade alterations differed in cognitive profiles from healthy controls, but not in PD-related motor symptoms or demographics. The rate of directive errors in the antisaccade task was increased in clusters 1 and 2. Further, cluster 1 was defined by a general disinhibition of reflexive saccades and executive dysfunction in the neuropsychological evaluation. In cluster 2, prolonged saccade latencies and hypometria were accompanied by multidomain cognitive impairment. The cluster 3 showed increased antisaccade latency and vertical hypometria despite lack of evidence for cognitive impairment. Our results suggest that there may be at least two opposing patterns of saccade alterations associated with cognitive impairment in PD, which may explain some of the contradictory results of previous studies.  相似文献   
259.
The discriminant validity of measures of job involvement, job satisfaction and organizational commitment was tested with data from 467 army officers in Sweden. Confirmatory-factor analysis showed a close fit between the proposed three-factor model and the data. Further, six of eleven job and health correlates related differently to the three attitude vairables. The results indicate that job involvement, job satisfaction and organizational commitment represent three empirically distinct constructs. Implications for future research discussed.  相似文献   
260.
Computerized medical personal registers are created for administrative purposes but are frequently used in research. It can be shown that this divergence of aims deeply affects the validity of the diagnosis in register research. The diagnostic process is embedded within the process of creating the data base. This process is guided by the aims for making diagnosis. Five different aims for making diagnosis in clinical practice have been analysed and eight suggestions for validity control are proposed on the basis of the study.  相似文献   
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