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961.
本研究对总装备部·绵阳八一帐篷学校的小学生进行创伤症状调查研究,了解震后一年半小学生的心理健康状况。方法:使用儿童创伤症状量表简版(TSCC-A)对八一帐篷学校3~6年级小学生进行评估。结果:(1)八一帐篷学校的小学生震后一年半最为突出的创伤症状是焦虑,其次为抑郁和分离症状;(2)在创伤症状得分上不存在性别差异性,但是存在年级差异性,三年级学生创伤症状得分均低于其他年级学生;(3)震后一年半学生创伤症状比震后半年学生创伤症状有所减轻。结论:灾区小学生心理健康状况仍存在一些问题,焦虑、抑郁等症状仍比较明显,还应进行持续的心理危机干预。 相似文献
962.
963.
What is the best account to explain the object-based attentional benefit—that is, the spread of attention within an attended object or prioritization of search across possible target locations within an attended object? Using a task in which the location of the target was known with certainty, in the present study we systematically manipulated the type (letters or bites) and the presentation time (long or short) of the target and flankers in order to test the effects of target–object integration and target presentation time on object-based attention. The results showed that an object-based effect could appear when the target was a bite, no matter whether the target presentation time was long or short; but when the target was a letter, an object-based effect was only observed when the target presentation time was short enough. These findings provide additional evidence supporting the argument of attentional spreading in object-based attention. However, this spreading is moderated jointly by target–object integration and the target presentation time. 相似文献
964.
Pour comparer l'impact de trois techniques d'acquiescement sur l'incitation au comportement charitable, on a demandéà 409 personnes de verser $2 à l'American Cancer Society. Cette requête fut immédiatement présentée dans trois groupes contrôle et précédée dans neuf groupes expérimentaux d'une demande préliminaire correspondant à une procédure d'acquiescement à requête multiple. On a d'abord demandé aux sujets soumis à la technique "pied dans la porte" de répondre à un questionnaire composé 10, 35 ou 60 items. On sollicitait d'abord $10, 25 ou 50 de la part de ceux confrontés à la situation "porte dans la figure"; et $0,50, 1 ou 1,50 de la part des sujets "ras des pâquerettes". Les résultats montrent que les méthodes $10 et 25 "porte dans la figure" furent les plus rentables. Les sujets contrôle et "ras des pâquerettes" donnèrent à peu près la même chose et les conditions "pied dans la porte" furent les moins productives. On discute, à partir de ces découvertes, de la valeur pratique et des inconvénients virtuels de l'application des techniques d'acquiescement à requête multiple pour stimuler le comportement charitable. 相似文献
965.
We investigated three issues with respect to the long-term serial recall of adults. First, retention interval was manipulated to obtain uncontaminated measures of long-term serial recall. Second, we compared serial recall of concrete and abstract nouns to determine how these materials might interact with various learning strategies over time. Third, control group participants were asked to describe the learning strategies used, allowing a comparison of technical mnemonic techniques with the spontaneously generated strategies of adults. We found that the delayed recall performance of participants who spontaneously used organizational or imagery-based strategies was comparable to that of those instructed in the method of loci and pegword technique. Word concreteness did not interact with any other variable. These results are discussed with regard to their implications for serial learning in educational settings. 相似文献
966.
Observers made systematic heading judgments in two experiments simulating their translation through an environment with only two trees. When those trees converged or decelerated apart, observers tended to follow the invariant information and make heading judgments outside the near member of the pair. When those trees accelerated apart, however, observers tended to follow the heuristic information and make judgments outside the far member, although this result was tempered by the angular separation between the trees and their relative acceleration. The simultaneous existence and use of invariants and heuristics are discussed in terms of different metatheoretical approaches to perception. 相似文献
967.
锌对细胞凋亡调控研究的一些思考 总被引:2,自引:0,他引:2
锌是机体必需的微量元素,它能够抑制细胞凋亡,也可以诱导细胞凋亡。阐述近年有关锌对细胞凋亡的研究结果,提出要全面,辩证地看待二者之间的关系。 相似文献
968.
Noise exclusion in spatial attention 总被引:5,自引:0,他引:5
Precue validity affects the performance of perceptual tasks. These spatial attention effects have been variously attributed to facilitation of processing, capacity allocation, or noise reduction. We used a new attention-plus-external (stimulus)-noise paradigm and model to identify the mechanisms of attention in cue-validity paradigms. A new phenomenon is reported: a large effect of location cue validity in an orientation identification task that specifically occurs when the stimulus is embedded in external (environmental or stimulus) noise. This result identifies the mechanism of the effect as external-noise exclusion, distinguished from stimulus enhancement that manifests itself only in noiseless stimulus environments. 相似文献
969.
The glare effect is an illusion in which a region appears self-luminous when flanked by gradients that decrease in luminance with distance from the region (Zavagno, 1999 Perception 28 835-838). This region also appears brighter than a surface of the same luminance. We investigated, using the paradigm of afterimages, whether a low-level mechanism at the level of the retina or LGN could account for this apparent brighter sensation. We first replicated the result from the literature that brighter and longer-lasting physical stimuli generate longer-lasting afterimages. We then compared the glare-effect stimuli with their counterpart controls, and found that the glare-effect stimuli did not give rise to longer-lasting afterimages. This suggests that the apparent brighter sensation of the glare effect is not due to a retinal or LGN mechanism, but must have a cortical origin. 相似文献
970.
In this study, we examine the suitability of a relatively new imaging technique, arterial spin labeled perfusion imaging, for the study of continuous, gradual changes in neural activity. Unlike BOLD imaging, the perfusion signal is stable over long time-scales, allowing for accurate assessment of continuous performance. In addition, perfusion fMRI provides an absolute measure of blood flow so signal changes can be interpreted without reference to a baseline. The task we used was the serial response time task, a sequence learning task. Our results show reliable correlations between performance improvements and decreases in blood flow in premotor cortex and the inferior parietal lobe, supporting the model that learning procedures that increase efficiency of processing will be reflected in lower metabolic needs in tissues that support such processes. More generally, our results show that perfusion fMRI may be applied to the study of mental operations that produce gradual changes in neural activity. 相似文献