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271.
立体视觉的心理物理和VEP比较研究   总被引:2,自引:0,他引:2  
心理物理试验是研究立体视觉的主要方法。70年代VEP开始用于体视研究,并取得许多结果。由于VEP信号复杂,这些结果不能令人满意。本文使用心理物理试验和VEP对比方法对体视加以研究。我们的结果是:VEP波形中第一个正峰与刺激图形的亮度有关;N_2峰和P_3峰的潜伏期对判断体视存在与否有重要价值;本试验确定N_2峰潜伏期在体视存在时约为240ms—280ms,无体视存在时约为290ms—310ms;P_3峰潜伏期在体视存在时约为280ms—310ms,无体视存在时约为340ms—360ms;体视存在时的VEP与无体视存在时的VEP的互相关系数小于0.1;有体视的VEP其功率谱密度在8Hz附近有一峰;心理物理试验中使用强制选择得到的结果从VEP波形比较中可以确认是可靠的;有体视的VEP其N_2和P_3的潜伏期随视差变化呈现规律性改变。  相似文献   
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273.
Honeybees (Apis mellifera) were classically conditioned with odor as conditioned stimulus (CS), sucrose as unconditioned stimulus (US), and proboscis extension as response. The purpose of Experiment 1 (Ns = 26 and 27) was to look for facilitation of forward conditioning by CS-US overlap, but rapid conditioning without overlap left little room for improvement. In 2 further experiments, CS and US were simultaneous, and response to odor alone was measured in subsequent tests. In Experiment 2, a Simultaneous group (N = 25) responded more to the training odor than did an Unpaired control group (N = 25). In Experiment 3, a differentially conditioned Simultaneous group (N = 29) responded more to an odor paired with sucrose in training (S+) than to an odor presented alone (S-). The implications of the results for the problem of the role of amount of reward in honeybee learning are considered.  相似文献   
274.
Human analog tests of object permanence were administered to various breeds of adult dogs (Canis familiaris). Experiment 1 showed that the performance of terriers, sporting, and working dogs did not differ. Dogs succeeded in solving invisible displacement problems, but performance was lower than in visible displacement tests. Familiarity with the task had some influence because invisible displacement tests were more successful if they were preceded by visible displacement tests. In Experiment 2, odor cues from the target object and the hiding screens were available or were masked. Results confirmed that success was lower in invisible than in visible displacement tests and that these problems were solved on the basis of representation of visual information rather than on the basis of olfactory cues or of local rule learning. Dogs are compared with other species that display Stage 6 object permanence.  相似文献   
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276.
This study attempted to apply the relative deprivation theory to preferential selection research. Two questions were addressed in this context: First, does preferential selection cause feelings of injustice or deprivation? and, second, can the magnitude of such feelings of injustice be predicted? A questionnaire was designed to assess fairness perceptions of all types of selection outcomes: preferential selection; together with selection involving discrimination against minorities and selections without either forms of discrimination. Results showed that preferential selection caused feelings of injustice. The level of felt injustice associated with preferential selection was identical to that due to discrimination against minorities. Further, the magnitude of felt injustice due to preferential selection could be predicted by the size of the discrepancy in “performance-relevant merits” between the selected minority candidate and the unsuccessful majority candidate. The study also compared effects of the “self-other” comparison process, used in previous relative deprivation research, and a “other-other” comparison process on justice perception. Implications of the results for the application of relative deprivation theory to preferential selection research were discussed.  相似文献   
277.
Measures of spatial cognition, neighborhood knowledge, and neighborhood use from the research described by Walsh, Krauss, and Regnier (1981) were examined to determine if laboratory tests of spatial cognition were significant predictors of older adults' use of their neighborhoods. The overall results show that laboratory-based measures of spatial cognition and subjects' knowledge of their neighborhoods are both significant predictors of their use of neighborhood goods and services. The ability to learn and remember the location and orientation of objects, when contextual cues were not provided at test, was more predictive of the participants' neighborhood use than either the participants' number of years in the neighborhood or their mobility. Spatial memory as measured by the Educational Testing Service Building Memory task predicted neighborhood knowledge, which was predictive of neighborhood use.  相似文献   
278.
Elders exposed to either progressive or imaginal relaxation procedures reported significant relaxation effects and showed improvement on measures of personal functioning. The results of the Physical Assessment Scale of the Relaxation Inventory indicated that relaxation responses were acquired within and across sessions. Large, consistent changes in relaxation occurred in all 4 sessions. The Symptom Checklist-90-R, which measures self-reported personal adjustment, showed significant positive changes following relaxation training and at 1-month follow-up. Elders who imagined muscle tension release profited as much as those engaged in actual muscle tension-release activities. This finding is of importance for older adults who may experience physical limitations that contraindicate muscle-tension-release procedures.  相似文献   
279.
Confirmatory factor analysis of Wallston's Multidimensional Health Locus of Control Scale and Krantz's Health Opinion Survey was conducted using 197 nondiabetic and 171 diabetic older adults. Qualified support was found for the 3-factor structure of the Wallston measure when applied to older adults. The Krantz model provided a less-than-adequate representation of the older sample's data. When the items from these 2 measures were combined, a 4-factor structure was found. Multisample simultaneous factor analyses using LISREL revealed that the factor structures of the Wallston and the Krantz measures fit the diabetic and the nondiabetic samples fairly equivalently. Despite the similarities in factor structures, diabetic individuals reported greater belief in powerful others and less desire for behavioral involvement in the health-care process than did nondiabetics.  相似文献   
280.
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