Assessment and choice: an operant simulation of foraging in patches

Pigeons were presented with an operant simulation of two prey patches using concurrent random-ratio schedules of reinforcement. An unstable patch offered a higher initial reinforcement probability, which then declined unpredictably to a zero reinforcement probability in each session. A stable patch offered a low but unvarying reinforcement probability. When the reinforcement probability declined to zero in a single step, the birds displayed shorter giving-up times in the unstable patch when the ratio between the initial reinforcement probabilities in the unstable and stable patches was greater and when the combined magnitude of the reinforcement probabilities in the two patches was greater. When the unstable patch declined in two steps, the birds behaved as if their giving-up times were influenced heavily by events encountered during the most recent step of the double-step change. This effect was observed, however, only when the reinforcement probability in that step was .04, not when it was .06. All of these data agree with the predictions of a capture-probability model based on a comparison of the estimated probability of receiving a reinforcer in the current patch with that in alternative patches.     

Statistical inference for false positive and false negative error rates in mastery testing

This paper describes an asymptotic inferential procedure for the estimates of the false positive and false negative error rates. Formulas and tables are described for the computations of the standard errors. A simulation study indicates that the asymptotic standard errors may be used even with samples of 25 cases as long as the Kuder-Richardson Formula 21 reliability is reasonably large. Otherwise, a large sample would be required.This work was performed pursuant to Grant No NIE-G-78-0087 with the National Institute of Education, Department of Health, Education and Welfare, Huynh Huynh, Principal Investigator. Points of view or opinions stated do not necessarily reflect NIE position or policy and no official endorsement should be inferred. The editorial assistance of Joseph C. Saunders is gratefully acknowledged.     

Effects of Sensory Deficit on Phalanx Force Deviation During Power Grip Post Stroke

The effect of sensory deficits on power grip force from individual phalanges was examined. The authors found that stroke survivors with sensory deficits (determined by the Semmes-Weinstein monofilament test) gripped with phalanx force directed more tangential to the object surface, than those without, although both groups had similar motor deficits (Chedoke-McMaster and Fugl-Meyer), grip strength, and skin friction. Altered grip force direction elevates risk of finger slippage against the object thus grip loss/object dropping, hindering activities of daily living. Altered grip force direction was associated with altered muscle activation patterns. In summary, the motor impairment level alone may not describe hand motor control in detail. Information about sensory deficits helps elucidate patients' hand motor control with functional relevance.     

阅读中的眼跳目标选择问题

读者在阅读中面临如何选择眼跳落点位置的问题。研究者在有词间空格的字母文字中(如英语和德语)发现人们倾向于将眼跳落在词中心偏左的位置,这个位置被称为偏好注视位置(preferred viewing location,PVL)。中文文本并没有空格来标记词边界信息,这使得中文阅读的眼跳目标选择机制更加复杂。近年来,研究者从中央凹—副中央凹动态调节的角度研究了阅读中眼跳目标选择的机制。结果发现在中文阅读中眼跳目标选择受到中央凹和副中央凹信息加工的共同影响,而副中央凹的加工直接决定了眼跳落点位置。     

人口性别比例失衡对人类行为的影响

男女比例协调本是自然进化的规律。可在我国, 人口性别比例失调的现象日趋严重, 深入理解这一现象对社会产生何种影响已经成为一件刻不容缓的工作。进化心理学和社会人口学这两个领域近年来分别开展了一系列与此问题相关的研究, 从性选择、择偶、婚姻、亲本投资、暴力行为和经济行为六个方面全面研究人口性别比例对人类行为的影响。     

延迟命名任务中图词干扰效应的眼动研究

采用图-词分离呈现及眼动技术探讨在延时命名条件下图-词干扰效应发生的位置。结果发现：（1）延时命名图片时,仍出现图-词干扰效应和频率效应;（2）与命名干扰词相比,命名图片时图片的回视率高,注视时间长;（3）图片的注视时间也出现频率效应和图-词干扰效应。这说明即使在延时命名图片的条件下,目标词汇仍需要再次激活,频率效应和图-词干扰效应是发生在词汇化过程中,反驳反应排除理论的图-词干扰反应选择阶段的观点,支持了词汇化选择竞争的理论。     

心算活动中混合策略选择的ERP研究

考察问题大小、距离、奇偶及答案正误对心算策略选择的影响。采用先答案后算式的呈现方式, 记录了15名被试的64导ERP。研究发现, 在小问题中, 错误答案与正确答案相比, 诱发了算术不一致N400, 距离和奇偶因素影响其波峰及潜伏期。在大问题中, 距离和奇偶因素影响晚期正波, 近距离奇偶一致情境诱发了波幅较小的晚期正慢波。表明在混合情境, 距离比奇偶信息优先得到加工; 在小问题心算中距离和奇偶信息影响答案提取, 而在大问题心算中, 对于依靠距离信息较难直接判断的小距离问题, 在进一步的加工中会借助奇偶信息判断是否采用精确计算策略。     

基于自我相似面孔的亲缘选择与配偶选择行为

根据广义适合度理论, 自我相似面孔与亲缘选择和配偶选择行为密切相关。自我相似面孔可以促进个体的亲缘利他行为, 影响配偶选择行为。来自“夫妻相”、“性印刻”的描述性研究数据支持自我相似面孔与配偶选择偏好之间的相关关系。来自实验研究的数据, 结论尚不统一。有些证实自我相似面孔可以引发配偶选择偏好, 有些却不支持这一结论。最近的研究从内隐及外显认知上分离择偶过程中对自我相似面孔的偏好：认为偏好是内隐的, 一旦上升到意识层面便会消失。另有研究从性选择策略上对自我相似面孔偏好的原因进行解读。对自我相似面孔偏好的神经机制的研究也有一些新的发现。未来研究可借助fMRI等工具从认知过程及神经机制上对自我相似面孔偏好的现象作进一步探讨。