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891.
From mid-October 2001 through the end of November 2001, we collected fairly large sets of questionnaires from undergraduates at three public universities (Albany, NY, n = 507, Augusta, GA, n = 336, Fargo, ND, n = 526 ) to assess rate of acute stress disorder (ASD) and level of ASD symptoms following the September 11th attacks, rate of current posttraumatic stress disorder (PTSD) and level of PTSD symptoms, and current level of depressive symptoms resulting from the September 11th attacks. We also gathered information on exposure to media coverage of the attacks, connectedness to the World Trade Center (WTC) and personnel there, and degree of engagement in reparative acts such as giving blood, attending vigils. We found higher levels of ASD, ASD symptoms, PTSD and PTSD symptoms as a function of geographical proximity to New York City (and within the Albany site, proximity of students' homes) and gender. Exposure (hours of TV watched) was a predictor in some instances as was connectedness to WTC victims. ASD symptoms were the strongest predictor of subsequent PTSD symptoms. Path models accounted for over 60% of the variance in PTSD symptoms.  相似文献   
892.
893.
This study evaluated behavioral skills training (BST), in a multiple baseline across subjects design, for teaching firearm safety skills to 6 6- and 7-year-old children. Similar to previous research with 4- and 5-year-olds, half of the children acquired the safety skills following BST and half acquired the skills following BST plus in situ training.  相似文献   
894.
Although it is now well established that object concepts are situated within broader systems of theoretical knowledge, it is less clear how theories influence the use of object concepts at various points throughout the continuum of expertise. Two studies were conducted to investigate the impact of specific theories (concerning dinosaurs) and overarching framework theories (of biology) on children's and adults' performance on categorization tasks involving familiar and less familiar concepts. Although expertise increased the quantity of deep feature knowledge possessed by children and increased their understanding of biologically adaptive relations among features, few aspects of children's performance generalized beyond highly familiar dinosaurs. Children's specific theories related to dinosaurs were empirically constrained and relatively dissociated from other types of biological knowledge. The interaction of specific concept knowledge with broader framework theories of biology throughout the continuum of expertise is considered.  相似文献   
895.
Three studies involving 478 undergraduates examined the perceived importance of observable actions versus mental states in revealing the "true self"-the authentic and fundamental nature of a target person. Results suggest that when people have only limited information about a target, they believe that an action is more diagnostic of the individual's true self than the accompanying mental state. When participants have knowledge concerning chronic dispositional tendencies of the target, however, they judge that a chronic mental state is more diagnostic of the true self than a chronic action tendency. Considered together, the findings suggest that people conceptualize the true self as a relatively private entity but nevertheless believe that an action of a little-known person may be particularly informative about that individual. Perceived diagnosticity of the true self was partially mediated by inferences concerning the relative stability of actions versus states but not by inferences of volition.  相似文献   
896.
In this study, we evaluated observers' ability to compare naturally shaped three-dimensional (3-D) objects, using their senses of vision and touch. In one experiment, the observers haptically manipulated 1 object and then indicated which of 12 visible objects possessed the same shape. In the second experiment, pairs of objects were presented, and the observers indicated whether their 3-D shape was the same or different. The 2 objects were presented either unimodally (vision-vision or haptic-haptic) or cross-modally (vision-haptic or haptic-vision). In both experiments, the observers were able to compare 3-D shape across modalities with reasonably high levels of accuracy. In Experiment 1, for example, the observers' matching performance rose to 72% correct (chance performance was 8.3%) after five experimental sessions. In Experiment 2, small (but significant) differences in performance were obtained between the unimodal vision-vision condition and the two cross-modal conditions. Taken together, the results suggest that vision and touch have functionally overlapping, but not necessarily equivalent, representations of 3-D shape.  相似文献   
897.
Selection bias can be the most important threat to internal validity in intervention research, but is often insufficiently recognized and controlled. The bias is illustrated in research on parental interventions (punishment, homework assistance); medical interventions (hospitalization); and psychological interventions for suicide risk, sex offending, and juvenile delinquency. The intervention selection bias is most adequately controlled in randomized studies or strong quasi-experimental designs, although recent statistical innovations can enhance weaker designs. The most important points are to increase awareness of the intervention selection bias and to systematically evaluate plausible alternative explanations of data before making causal conclusions.  相似文献   
898.
In this study, we investigated orthographic influences on spoken word recognition. The degree of spelling inconsistency was manipulated while rime phonology was held constant. Inconsistent words with subdominant spellings were processed more slowly than inconsistent words with dominant spellings. This graded consistency effect was obtained in three experiments. However, the effect was strongest in lexical decision, intermediate in rime detection, and weakest in auditory naming. We conclude that (1) orthographic consistency effects are not artifacts of phonological, phonetic, or phonotactic properties of the stimulus material; (2) orthographic effects can be found even when the error rate is extremely low, which rules out the possibility that they result from strategies used to reduce task difficulty; and (3) orthographic effects are not restricted to lexical decision. However, they are stronger in lexical decision than in other tasks. Overall, the study shows that learning about orthography alters the way we process spoken language.  相似文献   
899.
Patients with Parkinson's disease (PD) exhibit deficits in perceptual and motor timing as well as impairments in memory and attentional processes that are related to dysfunction of dopaminergic systems in the basal ganglia. The aim of the present study was to assess the relationships existing between impaired duration judgments and defective memory and attention in PD patients. We compared time performance of medicated PD patients and control subjects on a duration reproduction task that is highly memory-dependent, and on a duration production task that could reveal effects of changes in the speed of internal time-keeping mechanisms. Each task was performed in a control counting condition and in a condition requiring divided attention between the temporal task and a concurrent reading task. Moreover, PD patients and control subjects were assessed on memory and attention using a battery of neuropsychological tests. The results revealed that in the concurrent reading condition of the reproduction task, duration judgments tended to be more variable in PD patients than in control subjects. Moreover, variability of duration reproductions was correlated with both measures of memory and of disease severity. In the concurrent reading condition of the production task, duration judgments were significantly shorter in PD patients than in control subjects, and accuracy of duration productions was correlated with scores on sub-tests of short-term memory. The findings suggest that the administration of dopamine did not entirely remove the memory deficits in PD patients. Moreover, DA treatment would have abnormally accelerated the rate of the internal clock leading to shorter duration productions in PD patients. The whole results indicate that dopamine administration in patients might have overshadowed the slowing rate of the internal clock usually reported in non medicated PD patients, without entirely restoring all of the memory functions.  相似文献   
900.
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