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961.
The present studies assessed the effect of behavioral inhibition on interactions of college students in mixed-sex groups. In Study 1, 20 participants were arranged into two dyadic groups based on self-rated measures of approach/withdrawal behavior. These dyads (inhibited men/uninhibited women; inhibited women/uninhibited men) were videotaped during an unstructured 5-min. interaction in a laboratory. Time series analysis indicated greater behavioral covariation in the inhibited men/uninhibited women dyads and less behavioral covariation in the inhibited women/uninhibited men dyads. Additional analyses indicated a relationship between inhibition and comfort experienced during the interaction. Inhibited participants, particularly women, reported feeling uncomfortable while interacting with an uninhibited male partner. A second study corroborated the findings reported in Study 1 and also noted elevated heart rate in the inhibited women. This increased discomfort in women appeared to be related to heightened self-consciousness during the interaction.  相似文献   
962.
In two experiments, adult participants explored a symmetrical three-tiered computer-simulated building that contained six distinctive objects, two on each floor. Following exploration, the objects were removed, and the participants were asked to make direction judgments from each floor, indicating the former positions of the objects on that floor and on higher and lower floors. Relative tilt error scores indicated a bias, in that targets that were higher than the test location were judged as consistently lower than their actual positions and targets that were lower than the test location were judged as consistently higher than their actual positions. Absolute tilt errors revealed an asymmetry, with more accurate and less variable tilt errors for judgments directed to lower floors than for judgments directed to higher floors. Experiment 3 ruled out an account of the findings that does not relate them to spatial memory. The results suggest that the superiority of downward over upward spatial judgments, previously reported in two-dimensional visual-spatial tasks, extends to navigational spatial memory.  相似文献   
963.
In our Outpatient Department, we studied 56 subjects (41 males, 15 females; aged 5-16 yr.) with Attention Deficit Hyperactivity Disorder (ADHD) with respect to hand use in functional tasks via parental report. Left-hand use was markedly preferred, compared to that of a control group, more for complex than simple and for external (touching food and objects) than internal (scratching, rubbing eyes) tasks, suggesting a deficit in cerebral control of right-hand use. More patients were reported to have a left-hand preference than in the non-ADHD population. Furthermore, extent of laterality was greater for complex than simple external tasks and for external than for internal.  相似文献   
964.
Two subjects participated in a 216 km ultramarathon with outside temperatures above 50 degrees C while several physiological and psychological parameters (cognitive performance assessed by a mental calculation task and an attentional task, subjective bodily experience, and lactate level) were evaluated throughout the race. Severe stress from dehydration, sleep deprivation, and total physical exhaustion are combined in a unique manner, allowing evaluation of their effects in a range far outside that obtainable in a laboratory setting. During the race the subjects answered a questionnaire about their actual bodily experiences, underwent 8 medical examinations, and performed two cognitive tests approximately every 35 kilometers. Analysis showed cognitive performance did not decrease steadily in a simple and gradual way but reached a peak in the morning of Day 2 after a short sleeping period and then decreased. In the early morning of Day 3, in general cognitive performance exhibited the worst results but increased differentially between the subjects again in the last test 1 km before the finish line.  相似文献   
965.
Driving is a complex behavior involving multiple cognitive domains. To identify neural correlates of driving performance, [15O]H2O positron emission tomography was performed using a simulated driving task. Compared with the resting condition, simulated driving increased regional cerebral blood flow (rCBF) in the cerebellum, occipital, and parietal cortices. Correlations between rCBF and measurements of driving performance were evaluated during simulated driving. Interestingly, rCBF in the thalamus, midbrain, and cerebellum were positively correlated with time required to complete the course and rCBF in the posterior cingulate gyrus was positively correlated with number of crashes during the task. These brain regions may thus play roles in the maintenance of driving performance.  相似文献   
966.
This study was set out to explore the prediction that dyslexics would be likely to have particular problems compared to control group, on response time task when 'driving' a car simulator. The reason for doing so stems from the fact that there is considerable body of research on visual processing difficulties manifested by dyslexics. The task was to drive a car and at the same time, the driver had to use either signal button on the right side of the wheel (condition 1) or a voice-activated microphone (condition 2) immediately when a road sign appears. In condition 1, the sign appears only in the mid-field zone and in condition 2, it appears in one of six possible positions in relations to the car ahead. As predicted, it was found that the dyslexics had significantly higher response time in both conditions than their controls. Dyslexics may have visual processing deficit which not only cause reading problems but also problems perceiving rapid changes in their environment such as responding on a sign when driving.  相似文献   
967.
The present study investigated dysarthric symptoms in children with cerebellar tumors. Ten children with cerebellar tumors and 10 orthopedic control children were tested prior and one week after surgery. Clinical dysarthric symptoms were quantified in spontaneous speech. Syllable durations were analyzed in syllable repetition and sentence production tasks. Localization of the cerebellar lesions were defined after manual transfer from individual 2D-MR images onto 3D images of a spatially normalized healthy brain. Cerebellar children showed few and mild clinical signs of dysarthria. No difference was present in the sentence production task compared to controls. In five cerebellar children, syllables were prolonged in the syllable repetition task after surgery. Syllable duration normalized in an additional four-week session in all but one case. The MR-analysis showed that superior paravermal cerebellar areas likely involved in dysarthria in adults (paravermal lobules HVI, Crus I) were not significantly affected. In children, speech impairments appear to be rare after cerebellar surgery because tumors most commonly affect posterior-inferior and medial parts of the cerebellum while critical cerebellar regions are likely spared. The results suggest a similar localization of speech functions in the cerebellum in children and adults.  相似文献   
968.
Alzheimer's disease (AD) subjects, healthy elderly, and young adults interpreted a series of novel noun-noun expressions composed of familiar object words. Subjects interpreted each item by selecting one of three possible definitions: a definition in which the referents of each noun were associated together in a particular context (e.g., rabbit cat: a cat that is raised by rabbits); a definition based on integrating the semantic attributes from each noun into a single referent (e.g., rabbit cat: a cat that has long ears and hops); and a semantic foil. The results show that the AD subjects selected significantly fewer integrational definitions and significantly more foils than healthy elderly subjects. Healthy elderly participants were also found to select significantly more foil definitions than the young adult subjects. These findings suggest that AD individuals have difficulty in integrating semantic features when interpreting novel noun-noun expressions and that both AD and healthy elderly individuals have morphosyntactic impairments related to the identification of the modifying and head nouns of noun-noun expressions.  相似文献   
969.
This study examined 5- and 6-year-olds' suggestibility and interviewer demeanor as joint predictors of their memory for a novel experience. Session 1 consisted of children taking part in a novel laboratory event. Session 2 took place after approximately a 1-week delay and consisted of children completing both a memory test concerning what happened during the prior event and the Video Suggestibility Scale for Children (VSSC). During the second session, the interviewer behaved either supportively or nonsupportively. Greater acquiescence on the VSSC was associated with fewer correct responses to misleading questions about the laboratory event in the supportive and nonsupportive conditions and with more errors in response to specific questions in the nonsupportive condition. Results indicate that individual differences in children's suggestibility are related to the accuracy of their memory for separate events, although some of these relations may vary depending on the context in which children are interviewed.  相似文献   
970.
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