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991.
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   
992.
993.
Patterns of manual preference and the extent to which preference provided a benefit in performance (movement time) were evaluated in 7 young adult capuchin monkeys (Cebus apella). Directions of preference were inconsistent within individual animals across home-cage activities, unimanual, and bimanual experimental tasks. Preferences were more strongly expressed in the experimental tasks than in the home cage. A left bias in the population for prehension, predicted by recent theories, was not evident in any setting. Movement time was moderately negatively correlated with degree of preference within experimental tasks. The benefit to performance conferred by lateral preference was not dependent on whether the right or left hand was preferred. Lateralization of prehension appears to be a flexible process in these monkeys, which can result in quickly realized benefits in some conditions.  相似文献   
994.
The story of Joseph in the Qur'an has been approached by many non‐Muslim writers1 who were content to list which details of the biblical story have been missed out from the biblical story and which points have been added, maintaining that these had their origins in biblical or other Jewish sources. Our treatment here concentrates on the texts of the story in the Qur'an and the Old Testament, attempting to identify the differing functions and preoccupations of the two accounts in their respective contexts, to show how this difference affects the choice of material and the treatment given to it. This article concludes that the two versions should be approached by readers, Muslims and non‐Muslims, with this difference in mind in order to appreciate the message and the qualities of each.  相似文献   
995.
This study examines the factor structure of the Mobility Inventory for Agoraphobia and attempts to validate the inventory, using an Australian sample of agoraphobic patients, by comparison with other scales. One hundred twentyfour panic disorder with agoraphobia patients were studied. Factor analysis showed that a two-factor solution was the most suitable both when subjects were accompanied (accompanied condition) and when alone (alone condition). Factor I represented public, crowded, or social situations including department stores, supermarkets, restaurants, theaters, and panics and social gatherings. Factor II reflected enclosed or riding situations such as elevators, parking garages, enclosed spaces, and riding in subways or airplanes. These two factors accounted for 46.6% and 44.3% of the variance on the accompanied condition and the alone condition, respectively. The Mobility Inventory was significantly correlated with the Agoraphobia factor of the Fear Questionnaire and the Social Avoidance and Distress scale. These results indicated that the Mobility Inventory is a valid instrument to measure agoraphobic behavior.  相似文献   
996.
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   
997.
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999.
PIGEONS ARE SENSITIVE TO THE SPATIAL ORGANIZATION OF COMPLEX VISUAL STIMULI   总被引:1,自引:0,他引:1  
Abstract— Two experiments investigated the role of spatial organisation in the discrimination and generalization of complex visual stimuli by pigeons. In Experiment 1, after pigeons had been trained to discriminate line drawings of four objects, they were tested with novel pictures in which the same component parts of the objects were spatially rearranged. The spatially scrambled pictures led to a dramatic drop in recognition accuracy, hut responding remained above chance. In Experiment 2, pigeons reached a high level of discriminative performance when required to choose among four different spatial arrangements of the same object parts. These results confirm Cerella's (1980) conclusion that pigeons discriminate the component parts of complex visual stimuli, but. unless it is assumed that the scrambling deleted or created emergent features, the results disconfirm his conclusion that spatial organization plays no role in pigeons' picture perception.  相似文献   
1000.
Depression in some patients with spinal cord injuries may be clinically significant and, when present, should be treated to decrease morbidity including decreased physical functioning. Depression associated with spinal cord injury (SCI) may be misevaluated, due to (1) nonspecific multifactorial production of depression symptoms and (2) SCI-specific decrease in somatic sensory central nervous system input. The Somatic Suppression Hypothesis suggests that SCI patients have difficulty experiencing any intense emotion because of suppression of physiological arousal. In addition, cognitive processes that may reduce depression in SCI patients include: (1) attribution of somatic symptoms of depression to medical (biological) causes, (2) realistic, positive expectations for physical improvement, and (3) the perception that the disability of the SCI is only minimally related to the patient’s self-care after complete evaluation. Health personnel should accept lack of depression in SCI, and should encourage positive realistic expectations of recovery.  相似文献   
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