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961.
Cheng Ken; Shettleworth Sara J.; Huttenlocher Janellen; Rieser John J. 《Canadian Metallurgical Quarterly》2007,133(4):625
Spatial judgments and actions are often based on multiple cues. The authors review a multitude of phenomena on the integration of spatial cues in diverse species to consider how nearly optimally animals combine the cues. Under the banner of Bayesian perception, cues are sometimes combined and weighted in a near optimal fashion. In other instances when cues are combined, how optimal the integration is might be unclear. Only 1 cue may be relied on, or cues may seem to compete with one another. The authors attempt to bring some order to the diversity by taking into account the subjective discrepancy in the dictates of multiple cues. When cues are too discrepant, it may be best to rely on 1 cue source. When cues are not too discrepant, it may be advantageous to combine cues. Such a dual principle provides an extended Bayesian framework for understanding the functional reasons for the integration of spatial cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
962.
Perceived awareness and caring, or beliefs about how much parents and peers know and care about students' behavior, was assessed in relation to students' drinking patterns. Prior to and at the end of the first semester at college, participants completed Web-based surveys assessing alcohol use, family and social motives, and perceived awareness and caring from parents and peers. Family motives moderated the effect of perceived parental awareness and caring on the quantity of high school alcohol use, whereas social motives moderated the effect of perceived peer awareness and caring on frequency and quantity of college drinking. Longitudinally, college alcohol use was predicted by perceived awareness and caring from parents. Perceived awareness and caring may affect alcohol use whereby parents exert influence during high school but peers are more influential in college. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
963.
Hourihan Kathleen L.; Goldberg Samantha; Taylor Tracy L. 《Canadian Metallurgical Quarterly》2007,61(2):91
This study examined whether spatial location mediates intentional forgetting of peripherally presented words. Using an item-method directed forgetting paradigm, words were presented in peripheral locations at study. A recognition test presented all words at either the same or a different location relative to study. Results showed that while recognition of Remember words was unaffected by test location, when Forget words were presented in the same location at test as at study, recognition accuracy was significantly greater than when presented in a different location. Experiment 2 showed that the speed to localize a previously studied word was faster when it was presented in the same rather than a different study-test location but that the magnitude of this spatial priming was unaffected by memory instruction. We suggest that the location of peripherally presented words is represented in memory and can aid the retrieval of poorly encoded words. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
964.
Fouriezos George; Capstick Gary; Monette Fran?ois; Bellemare Christine; Parkinson Matthew; Dumoulin Angela 《Canadian Metallurgical Quarterly》2007,61(4):277
The flash-lag effect is a visual illusion wherein intermittently flashed, stationary stimuli seem to trail after a moving visual stimulus despite being flashed synchronously. We tested hypotheses that the flash-lag effect is due to spatial extrapolation, shortened perceptual lags, or accelerated acquisition of moving stimuli, all of which call for an earlier awareness of moving visual stimuli over stationary ones. Participants judged synchrony of a click either to a stationary flash of light or to a series of adjacent flashes that seemingly bounced off or bumped into the edge of the visual display. To be judged synchronous with a stationary flash, audio clicks had to be presented earlier--not later--than clicks that went with events, like a simulated bounce (Experiment 1) or crash (Experiments 2-4), of a moving visual target. Click synchrony to the initial appearance of a moving stimulus was no different than to a flash, but clicks had to be delayed by 30-40 ms to seem synchronous with the final (crash) positions (Experiment 2). The temporal difference was constant over a wide range of motion velocity (Experiment 3). Interrupting the apparent motion by omitting two illumination positions before the last one did not alter subjective synchrony, nor did their occlusion, so the shift in subjective synchrony seems not to be due to brightness contrast (Experiment 4). Click synchrony to the offset of a long duration stationary illumination was also delayed relative to its onset (Experiment 5). Visual stimuli in motion enter awareness no sooner than do stationary flashes, so motion extrapolation, latency difference, and motion acceleration cannot explain the flash-lag effect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
965.
Boutet Isabelle; Milgram Norton W.; Freedman Morris 《Canadian Metallurgical Quarterly》2007,121(3):270
Using a comparative neuropsychological approach, the authors compared performance of younger and healthy older adults ages 65 and over on tasks originally developed to measure cognition in animals. A battery of 6 tasks was used to evaluate object discrimination, egocentric spatial abilities, visual and spatial working memory, and response shifting. Older adults performed more poorly than younger adults on tasks that evaluate egocentric spatial abilities, response shifting, and to a lesser extent object recognition. The two groups did not differ for tasks that evaluate spatial working memory and object discrimination. The impairments the authors observed in tasks that evaluate response shifting and object recognition are consistent with those found in canines and primates as well as those found in Alzheimer's disease. The results are consistent with the notion that cognitive processes supported by the amygdala and the orbitofrontal cortex are among the first to decline with increasing age in both humans and animals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
966.
研究了一种新的非相干分布源模型。采用Jacobi-Anger级数展开,使得模型误差仅仅和级数展开的阶数有关,而和分布源空间扩展角度无关。当JA级数的阶数足够高时,分布源模型误差将会被控制在一个足够小的范围内,避免了以往利用Taylor级数展开的分布源模型中,当空间扩展角度增大时模型误差急剧增大的缺陷;利用多个对称分布能够合成非对称分布的原理,采用两个高斯分布来构造非对称分布,当控制这两个高斯分布之间的比例,非对称分布的形状也随之发生改变。新模型突破了以往分布源模型中对空间扩展角度以及分布形式的限制,具有广义性。将新模型与最速下降法进行结合,可以得到新的方位估计(DOA)。计算机仿真验证了理论的正确。 相似文献
967.
968.
为了克服噪声对语音识别系统的影响,提出了一种基于主曲线的说话人自适应方法,这种方法可以通过一组主曲线描述所有状态的特征统计信息和码本参数之间的关系,并利用特征统计量在主曲线上的投影更新码本.当有背景噪声存在时,这种方法可以有效修正状态的特征统计信息以减弱或去掉噪声的影响.在863大词汇量连续语音识别数据库上的实验结果证明:这种方法相对于基线以及本征音说话人自适应算法,系统识别性能都有明显的提高. 相似文献
969.
970.
The authors investigated how 3- and 4-year-old children and adults use relative distance to judge nearbyness. Participants judged whether several blocks were by a landmark. The absolute and relative distance of the blocks from the landmark varied. In Experiment 1, judgments of nearbyness decreased as the distance from the landmark increased, particularly for 4-year-olds and adults. In Experiment 2, 4-year-olds and adults were more likely to judge objects at an intermediate distance as by the landmark when intervening objects were absent than when intervening objects were present. In Experiment 3, participants of all ages were more likely to judge objects at a short distance as by the landmark when intervening objects were absent. Reliance on relative distance to judge nearbyness becomes more systematic and applicable to larger spatial extents across development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献