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981.
Andersen GJ Cisneros J Atchley P Saidpour A 《Journal of experimental psychology. Human perception and performance》1999,25(1):256-269
In the present study an alternative analysis to tau was considered that was based on perceived speed and size and that assumed constant deceleration for the detection of collision events. Observers were presented with displays simulating a 3-D environment with obstacles in the path of observer motion. During the trial, observer motion decelerated at a constant rate and was followed by a blackout prior to the end of the display. Observers had to detect which trials resulted in a collision. The results indicate that collision detection varied as a function of the size of the obstacles, observer speed, and edge rate--findings not predicted by an analysis of tau. The results suggest that observers use an analysis based on speed and size information. A model that assumes constant deceleration is proposed for braking control. 相似文献
982.
Willcutt EG Hartung CM Lahey BB Loney J Pelham WE 《Journal of abnormal child psychology》1999,27(6):463-472
This study examines the clinical utility of behavior ratings made by nonclinician examiners during assessments of preschool children with Attention-Deficit/Hyperactivity Disorder (AD/HD). Matched samples of children with (n = 127) and without (n = 125) AD/HD were utilized to test the internal, convergent, concurrent, and incremental validity of ratings completed by examiners on the Hillside Behavior Rating Scale (HBRS). Results indicated that HBRS ratings were internally consistent, possessed sufficient interrater reliability, and were significantly associated with parent and teacher reports of AD/HD when controlling for age, gender, intelligence, and symptoms of other psychopathology. HBRS ratings also were significantly associated with other measures of functioning, and provided a significant increment in the prediction of impairment over parent and teacher report alone. These findings suggest that behavioral ratings during testing provide a unique source of clinical information that may be useful as a supplement to parent and teacher reports. 相似文献
983.
Hemispheric asymmetry in lexical decisions: the effects of grammatical class and imageability 总被引:1,自引:0,他引:1
It has been suggested that neural systems for lexical processing of nouns and verbs are anatomically distinct. The aim of the present study was to investigate if brain asymmetry for the processing of these two grammatical classes is also different. Neurologically intact adults performed a lateralized lexical decision task with grammatically unambiguous words of high, medium, and low degrees of imagery. For error scores a right visual field (RVF) advantage and an overall effect of imageability were obtained. For latency scores grammatical class and imageability modified visual field differences: in the noun class a RVF advantage was obtained only for low imagery nouns, while for the verbs the RVF advantage was present for both medium and low imagery verbs. These results suggest that the participation of right hemisphere neural systems in the processing of verbs is more limited than in the processing of nouns. 相似文献
984.
985.
It is generally assumed that in catching a fly ball, an efficient strategy for dealing with the horizontal component of the ball's trajectory is for the observer to keep the angular position of the ball constant with respect to his head. That strategy is called the constant bearing angle or CBA strategy. Maintenance of angular constancy results in the simultaneous arrival of both observer and ball at the landing spot. The authors analyzed the approach behavior of 26 subjects in a ball-interception task with straight paths for both the subjects and the ball. Subjects moved at a velocity that maintained a close-to-constant horizontal angular position of the ball with respect to the end effector throughout the approach phase rather than a constant bearing angle with respect to their head. Velocity adaptations occurred as a function of the changes in the angular velocity of the ball in such a way that a positive or negative angular velocity was canceled. Thus, an actor following the CBA strategy does not need to know where and when the ball will arrive (i.e., a predictive strategy), because reliance on the CBA strategy ensures that he will make the appropriate adaptations that enable him to arrive at the right place in the right time. 相似文献
986.
Age differences in adults' memory for performed actions (e.g., wave hand) are sometimes smaller than age differences in memory for nonperformed phrases. In this study, we examined the conditions under which performance reduces age differences in recall. Younger and older adults performed or read verb-noun phrases that were either related (e.g., actions performed in a kitchen) or unrelated. Performance did not reduce age differences in recall of the exact verbs and nouns used to describe an action, but performance did reduce age differences in memory for the gist of related actions. Older adults especially had difficulty recalling the exact verb used to describe the action. These results suggest that older adults may have better memory for actions than is revealed by tests of verbatim recall. They may remember performing the action but not remember the exact words used to describe the action. 相似文献
987.
本实验旨在探索儿童对抽象图画情绪寓意敏感性的发展规律以及文化因素的影响。被试年龄跨度从 5岁至高中学生。根据被试利用形态、主题、情绪等图片特性作为识辨依据的特点来发现规律。儿童对抽象图画寓意敏感性的发展与表征水平相关。年幼儿童只能利用颜色或图形等单一信息维量进行判断 ,年长儿童及中学生可以综合利用形态、主题、情绪等多个维量判断。在寓意明确的图片识辨中 ,儿童对积极寓意的识辨成绩较优。在双关寓意的图片识辨中 ,儿童组倾向于选择具有积极寓意的线索 ,而中学生组会受到识辨经验的影响。文化与教育方式影响儿童对抽象图画情绪寓意的理解。中国幼教方式有助于儿童对图画认知与情绪成分的识辨。 相似文献
988.
989.
20世纪欧洲大陆思想发展过程中一直有一种最为怪癖的现象,就是对自然科学缺乏研究。的确,科学文献似乎否认哲学有超乎生活经验的立足点,并力求以这种方式采取一种客观陈述的姿态。分析的科学哲学采取了这种表面上有价值的姿态,并且以文化和历史要素相结合为代价而得以发展。分析的科学哲学家们把他们的工作看作是使自然科学的方法形式化,他们的兴趣不是专注于文化的、历史的和个人的因素能够成为决定因素的发现过程以及其他领域。然而,科学的知识也像一切知识一样,涉及对某人揭示(诉说)某事。科学探讨意义,这些意义就是体现在语… 相似文献
990.
一、有关技术的传统概念技术不过是人的劳作而已。它既是一种人为的事物也是一种人为的发明过程,其目的是由人制定的,从而也是由人所贯彻的。这就是从古至今技术的哲学人类学背景:从柏拉图的《普罗泰戈拉篇》到卡普(Kapp)和该伦(Gehlen)。他们都将技术说成是必然,因为人是一种有缺陷的生灵,而且他们对技术目的也都是在这样的标题下进行讨论,如加强、延伸以及替代我们可怜的人类器官或肢体,为的是生存竞争或改善我们的境况。但是,这种对技术的传统理解过于狭窄了,因为它没有涵盖这些东西,如教堂的建造、金字塔和庙宇,这些东… 相似文献