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831.
This study examined whether chronic physical exercise activity is associated with better neurocognitive performance in older adults. One hundred five men participated in 1 of 3 age groups (18-28, 35-45, and 60-73). For each age group, subjects were classified as high or low in fitness on the basis of self-reported activity levels and the results of a submaximal bicycle ergometer test. A comprehensive battery of neuropsychological tests was administered to each subject, and older subjects scored significantly lower than the younger groups on most tests. Significant differences between high- and low-fit subjects were found only on tasks with heavy visuospatial demands, and these differences were most notable in the older adult group. These findings suggest that participation in aerobic exercise activity selectively preserves some cognitive functions that normally decline with age. The benefits of activity appear to be most evident on tasks that require visuospatial processing.  相似文献   
832.
Gerontologists have long been concerned with the impact of individual-difference factors on memory. This study used a large sample (N = 2,495) of adult volunteers aged 18 to 90 years to determine if a set of individual-difference variables--vocabulary, education, depression, gender, marital status, and employment status--mediates the effects of aging on a wide range of laboratory-analogue tests of everyday memory. The data indicated that age was consistently the most significant predictor of memory performance, followed by vocabulary and gender. Vocabulary totally mediated age effects on a prose memory measure, and partial mediation of aging effects--primarily by vocabulary and gender--was observed on 5 other memory tests. These data suggest that when health samples of volunteers serve as research subjects, these individual differences can affect some memory test scores, but age remains the best overall predictor of memory performance.  相似文献   
833.
Recent research on individual psychological assessments for personnel decision-making purposes has indicated a great deal of variability in practice. This study compared the responses of psychologists who evaluated the same set of assessment protocols on the basis of graduate training and professional affiliation. Results indicated few differences in evaluations of those assessed or in the way assessments were conducted. Concerns about training for and the practice of individual assessment are discussed.  相似文献   
834.
835.
Catharine MacKinnon's investigation of the role of sexuality in the subordination of women is a logical culmination of radical feminist thought. If this is correct, the position of her work relative to radical feminism is analogous to the place Parmenides's work occupied in ancient Greek philosophy. Critics of MacKinnon's work have missed their target completely and must engage her work in a different way if feminist theory is to progress past its current stalemated malaise.  相似文献   
836.
The purpose of this pilot study was to assess the effectiveness of a brief test user orientation program on increasing service station managers' familiarity with a few key employment testing issues, including their familiarity with theModel Guidelines for Preemployment Integrity Testing Programs. The obtained results reveal that even a brief orientation program was able to significantly increase the managers' stated degree of familiarity with testing issues.  相似文献   
837.
838.
The development of competence was studied in a longitudinal sample of 98 children, with measurement points when the children were 7, 10, and 12 years old. Competence was defined in terms of adequate adaptation to developmental tasks, both on a general and on a domain-specijic level. The general form of competence was measured by ego-resiliency, reflecting fexibility and ability to solve developmental problems Domain-specific competencies were measured by school achievement and social preference. The results showed that ego-resiliency was related to the two domain-specific competencies, although the hypothesized causal direction from general competence to specific competencies was not supported. Both domain-specific competencies were found to have a feedback effect on ego-resiliency. This feedback effect was stronger for social preference. These results suggest a transactional relationship between general and domain-specific competencies, and point to the importance of domain-specific competencies (especially social preference by the peer group) in the development of general competence in the child.  相似文献   
839.
Kelley and Stahelski's (1970) triangle hypothesis states that competitors hold homogeneous views of others by assuming that most others are competitive, whereas cooperators or pro-social people hold more heterogeneous views by assuming that others are either cooperative or competitive. To evaluate the triangle hypothesis, this study examines differences between pro-socials, individualists, and competitors not only in their expectations about others' choice behaviour, but also in the confidence with which such expectations are held. It was found that pro-social subjects expected more cooperation than individualists and competitors. More importantly, as predicted on the basis of the triangle hypothesis, pro-socials were less confident about their expectations than competitors, with individualists holding intermediate levels of confidence.  相似文献   
840.
The present research examined whether line-ups based on target (‘suspect’) face similarity are biased or suggestive. Four experiments are described in which subjects constructed photographic line-ups by selecting foils similar in appearance to a target. Later, another group of subjects who had not seen the faces before (mock witnesses) were asked to pick out the targets from the line-ups. All four experiments showed that mock witnesses selected the target significantly more often than expected by chance, thereby demonstrating suggestiveness. Three alternative line-up construction methods were also evaluated. In these methods, foil selection was based not only on target similarity but also on similarity with one or more of the other line-up faces. Results showed that alternative line-up targets were not selected significantly more often than chance, suggesting that bias was reduced. An overall analysis showed that the alternative line-ups were significantly less suggestive than target-based line-ups. The results indicate that foil selection procedures that incorporate foil-to-foil similarity produce fairer line-ups than those exclusively based on target similarity.  相似文献   
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