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Recent studies point to a major role for alpha2-containing GABA-A receptors in modulating anxiety. However, the possible implication of GABA-A receptors containing the alpha3 subunit on anxiety is less known. The aim of this study was to examine the effects of SB-205384 (0.5-4 mg/kg, i.p.), an alpha3 subunit positive modulator of GABA-A receptor, on anxiety tested in the elevated plus-maze in male mice, using classical and ethological parameters. Mice treated with SB-205384 showed an increase in the frequency of entries and the time spent in open arms, as well as a reduction in the time spent in closed arms, as compared with the control group. A notable increase of "head-dipping" unprotected and a reduction of "stretched-attend posture" protected was also evident. These findings indicate that SB-205384 exhibits an anxiolytic-like profile in the elevated plus-maze test, suggesting that GABA-A receptors which contain the alpha3 subunit might be involved in regulation of anxiety. 相似文献
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Progress in the Molecular-Genetic Study of Intelligence 总被引:3,自引:0,他引:3
ABSTRACT— The past decade has seen a major shift in the genetic study of human intelligence; where classic studies aimed to quantify the heritability of intelligence, current studies aim to dissect this heritability into its molecular-genetic components. Five whole-genome linkage scans have been published in the past year, converging on several chromosomal (or genomic) regions important to intelligence. A handful of candidate genes, some of which lie in these genomic regions, have shown significant association to intelligence and the associations have been replicated in independent samples. Finding genes brings us closer to an understanding of the neurophysiological basis of human cognition. Furthermore, when genes are no longer latent factors in our models but can actually be measured, it becomes feasible to identify those environmental factors that interact and correlate with genetic makeup. This will supplant the long nature–nurture debate with actual understanding. 相似文献
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VIQ-PIQ differences have been studied in children with autism and Asperger syndrome but have not been studied in a separate group of children with PDD-NO, although, PDD-NOS has a much higher prevalence rate than autism and deficits in communication and social interaction are severe. The Wechsler Intelligence Scale for Children-Revised (WISC-R) was administered to 100 children, aged 6-12 years, with PDD-NOS (n = 76), autism (n = 13), and Asperger syndrome (n = 11). PDD-NOS was diagnosed using explicit research criteria. No overall differences between VIQ and PIQ were found in PDD-NOS and autism. Peaks in the subtest scores on Information, Similarities, Picture Arrangement, and Mazes, and troughs in the subtest scores on Comprehension, Digit Span, and Coding were demonstrated in children with PDD-NOS. Their score on the Freedom from Distractibility factor was lower than the scores on the Verbal Comprehension factor and the Perceptual Organization factor. Children with PDD-NOS seemed to have a similar VIQ-PIQ profile as children with autism, and on the subtest level children with PDD-NOS showed some similarities to children with Asperger syndrome or autism. It was not possible to distinguish PDD-NOS from autism or Asperger syndrome by using IQ scores. 相似文献
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One hundred twenty-two women participated in a study of the relationship between acquaintance/stranger rape and the respective variables of ego-identity achievement (attainment of self-image during adolescence that integrates one's ideas of what one is and what one wants to be) and perception of risk in intimacy (perception of close interpersonal relationships as a risky proposition). Results showed that compared to women who had not been sexually assaulted, survivors of rape in general reported lower ego-identity achievement and greater perception of risk in intimacy. Focusing on acquaintance rape and stranger rape with age at the time of assault as possible moderator, it was found that lower ego-identity achievement was systematically related to acquaintance rape in women who had been raped during their adolescent years, but not in survivors of rape during adulthood. Perception of risk in intimacy was significantly higher among women who had been raped when adolescents compared to those who had been raped during adulthood, but only in relation to acquaintance rape. 相似文献
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Sarah J. Cotton Maureen F. Dollard Jan de Jonge 《International journal of stress management》2002,9(3):147-162
It is imperative that the university environment be supportive and capable of nurturing optimal learning and performance in students. Using job design and work stress theories, the study assessed relationships between psychosocial work characteristics, well-being and satisfaction, and performance in a random sample survey of Australian university students (N = 176). Methodological improvements were a time lag between survey and performance measures, an objective measure of performance, and LISREL structural equation modeling. Results showed high levels of psychological distress and low levels of satisfaction, both linked to high demands combined with low control. In accord with the happy-productive student hypothesis, satisfaction mediated the impact of the work environment on performance. Reengineering the design of the student work environment may therefore improve performance outcomes (student grades) through enhancing satisfaction. 相似文献
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The primary purpose of the study was to identify event-based prospective-memory tasks that provide sensitive and reliable tools for assessing effects of normal aging in prospective-memory performance. Four prospective-memory tasks were selected from the literature or were newly developed, with the tasks differing on various dimensions that, for theoretical reasons or based on previous evidence, might determine task sensitivity to age effects on prospective-memory performance: perceptual saliency of prospective target events, frequency of occurrence of prospective target events, complexity of prospective-memory instructions, and provision of feedback after prospective-memory errors. Two of the four tasks yielded large and robust age effects on prospective-memory performance. Correlational analyses suggested that these age effects on prospective-memory performance were mediated, at least in part, by a reduced ability of older adults to maintain prospective intentions in a highly activated state and not by age effects on basic mental speed alone. 相似文献