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101.
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A study is reported in which the relations among normal aging, source amnesia, and frontal lobe functioning were explored. Twenty-four older adults (aged 60-84 years) were tested on their ability to remember where they had acquired new factual information; they were also given the Wisconsin Card Sorting Test (WCST), a test of verbal fluency, and other psychometric tests. The degree of source amnesia in this normal sample correlated with age, verbal fluency, and some measures from the WCST. Source amnesia was not related to Performance IQ, however, or to a measure of fact recall. The implications for the relations among aging, memory, and frontal lobe functions are discussed. 相似文献
104.
Critical Flicker Fusion Thresholds (CFFTs) were measured in 644 elderly people identified from community-based general practice
records, and the relationship of CFFT with age was investigated. The CFFT was measured using the method of limits with mean
scores for three ascending (flicker/fusion) and three descending (fusion/flicker) presentations being recorded. The difference
between the ascending and descending means was found to be significantly correlated with age (r=−0.131,P<0.001) and may reflect a reduced sensitivity of the Central Nervous System to suprathreshold flicker with increasing age.
The results suggest that CFFT measurement has an important role to play in gerontological research as an objective measure
of cognitive aspects of the ageing process. 相似文献
105.
K. Blokker S. Bruin J. Bryden I. Houseman C. Okkerse C. Van der Meer A. P. Verkaik 《Knowledge, Technology, and Policy》1990,3(3):76-83
In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS).
Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as
cooperative unions and multinational companies are included. After considering the influence of the changing environment on
the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined.
Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and
what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences
with this strategic investment are evaluated. 相似文献
106.
Abstract— In our discussion of the articles in this Special Section, we ask how well the various methods employed in these investigations can be made to converge on a common issue. We review how current evidence from positron emission tomography, studies of event-related potentials, cognitive methods, lesion studies, and network models relates to the mental processing of an ambiguous word. While many puzzles remain, we are impressed by the promising possibility of bringing these different methods together to deal with an issue central to cognition. 相似文献
107.
Private and public sector managers were compared regarding their job characteristics and organizational commitment. We hypothesized that job characteristics would be positively related to commitment and that sector would moderate that relationship. Moderated regression analyses revealed partial support for both hypotheses. The existence of clarity and challenge were positively related to commitment. Job characteristics demonstrated a stronger relationship with commitment among private sector managers. Explanations for these findings and directions for future research are discussed. 相似文献
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109.
The current study tests for the presence of differential order effects in evaluation tasks with consistent and inconsistent evidence as predicted by the Hogarth and Einhorn (1992) belief-adjustment model. The results, based on both between-subjects and within-subjects experiments, demonstrate that there were significant recency effects with inconsistent evidence as predicted, larger recency effects when the inconsistent evidence was farther apart in subjective value as predicted, and significant recency effects even when subjects were given training designed to both help them understand the task as completely as possible and to be better able to assess the pieces of evidence. By including a within-subjects design, we were able to demonstrate that the difference in subjective value between two pieces of evidence is the primary factor influencing the magnitude of the recency effect, regardless of whether the evidence is consistent or inconsistent. This latter finding is unique and contrary to previous research and theory. 相似文献
110.
When subjects attempt to fake psychopathology on the MMPI, scores on subtle subscales tend to be lower than those of nonfaking subjects. Our study hypothesized that this paradox comes about because the subtle subscales have no predictive validity, but their face validity for psychopathology is the opposite of the keyed direction for psychopathology. Subjects who attempt to fake psychopathology do so on the basis of item content and thus achieve lower rather than higher scores. Three groups of 80 undergraduates took the MMPI under regular, faking-good, or faking-bad instructions. As expected, faking-bad subjects scored significantly lower than regular subjects on the 100 most subtle items, and this was due to their responses to those. 73 of the items whose face validity was misleading. The results are consistent with other work showing valid uses of subtle items in detecting deception. 相似文献