Talking and Thinking With Our Hands

ABSTRACT— When people talk, they gesture. Typically, gesture is produced along with speech and forms a fully integrated system with that speech. However, under unusual circumstances, gesture can be produced on its own, without speech. In these instances, gesture must take over the full burden of communication usually shared by the two modalities. What happens to gesture in this very different context? One possibility is that there are no differences in the forms gesture takes with speech and without it—that gesture is gesture no matter what its function. But that is not what we find. When gesture is produced on its own and assumes the full burden of communication, it takes on a language-like form. In contrast, when gesture is produced in conjunction with speech and shares the burden of communication with that speech, it takes on an unsegmented, imagistic form, often conveying information not found in speech. As such, gesture sheds light on how people think and can even play a role in changing those thoughts. Gesture can thus be part of language or it can itself be language, altering its form to fit its function.     

Sensitivity analysis of structural equation models

The main purpose of this paper is to investigate the sensitivity analysis of structural equation model when minor perturbation is introduced. Some influence measure that based on the general case weight perturbation is derived for the generalized least squares estimation. An influence measure that related to the Cook's distance is also developed for the special case deletion perturbation scheme. Using the proposed methodology, the influential observation in a data set can be detected. Moreover, the general theory can be applied to detect the influential parameters in a model. Finally, some illustrative artificial and real examples are presented. The research of the first author was supported by a Hong Kong UPGC grant. The authors are greatly indebted to two reviewers for some very valuable comments for improvement of the paper.     

Psychosocial work factors, physical work load and associated musculoskeletal symptoms among home care workers

This study was based on a questionnaire and included a group of home care workers (HCW) (n = 305) and a reference group of municipal employees (n = 694). The relationship between the work environment and musculoskeletal symptoms was analysed. The HCW were less satisfied with their control over their work and stimulus from their work and had a higher physical work load and prevalence of musculoskeletal symptoms, compared with the reference group. The Rate Ratio (RR) of neck and shoulder symptoms among HCW was 83 and 54 %, respectively, higher among those reporting a "high" psychological work load compared with those reporting a "low" load. The highest RR for a single risk indicator was 2.5, and this concerned low-back symptoms among HCW who often worked with twisted postures. A combination of "poor" psychosocial work environment and "high" physical work load produced the highest RR for work-related neck (RR = 2.57) and shoulder (RR = 2.13) symptoms.     

一般性注意资源限制对返回抑制的影响

通过探讨视空间和语义通道内的注意资源的限制对IOR的影响的4个实验,来验证“IOR的低级成分不受注意资源限制的影响和IOR的高级成分受注意资源限制的影响”的假设。实验1A和1B的结果表明,在基于空间位置的简单检测任务中,IOR的低级成分既不随语义通道内注意资源的减少而消减,也不随空间通道内注意资源的减少而消减。实验2A和2B结果表明,在基于客体特性的辨别任务中,IOR的高级成分既随语义通道内注意资源的减少而消减,又随空间通道内注意资源的减少而消减。因此,辨别任务中的IOR受一般性注意资源的限制。同时,实验结果还表明,IOR的高级成分对空间通道内的注意资源的需求要高于对语义通道内注意资源的需求     

工作记忆广度个体差异模型述评

探究工作记忆广度的个体差异对揭示工作记忆实质具有重要的意义,文章首先介绍了工作记忆广度任务的特点,其次,对目前工作记忆广度个体差异的主要理论模型进行阐述和评价,最后总结了可能影响工作记忆广度个体差异的主要因素。     

姿势干扰强度的心理预期效应

本研究基于经典快速举臂试验与落球试验范式, 采用表面肌电信号分析技术, 研究内、外姿势干扰强度的心理预期对腰部姿势肌肉和上肢动作肌肉预期姿势调节(APAs)和补偿姿势调节(CPAs)的影响, 探讨中枢神经系统(CNS)对内、外姿势干扰的控制策略。20名健康受试者先后完成不同负荷强度的快速举臂试验和落球试验, 同步采集腰部竖脊肌、腰部多裂肌和上肢肱二头肌的表面肌电信号, 计算肌肉预激活时间和APAs与CPAs积分肌电值, 观察内、外姿势干扰强度的心理预期对中枢APAs和CPAs控制机制的影响。结果显示内部姿势干扰条件下, 干扰强度的心理预期对腰部多裂肌、腰部竖脊肌和上肢肱二头肌的APAs强度有显著影响, 而对预激活时间和CPAs强度无显著影响; 外部姿势干扰条件下, 干扰强度的心理预期对腰部多裂肌、腰部竖脊肌和肱二头肌的APAs强度有显著影响, 对肱二头肌和腰部多裂肌预激活时间有显著影响, 而对CPAs强度无显著影响。突发可预期姿势干扰条件下姿势的快速反应是一个由CNS主导的神经肌肉运动控制过程。受姿势干扰强度心理预期的影响, CNS对内、外突发姿势干扰条件下腰部姿势肌肉的活动采取了不同的控制策略。在内部姿势干扰条件下, 干扰刺激发生时间明确, CNS主要通过对APAs强度的调节来实现姿势肌肉的优化控制; 而在外部姿势干扰条件下, 干扰刺激时间不明确, CNS则通过对局部稳定肌APAs预激活时间以及局部稳定肌和整体稳定肌APAs强度的双重调节实现姿势肌肉的优化控制。干扰强度的心理预期对姿势肌肉APAs和CPAs的作用表明, 心理预期效应主要源自于CNS对局部和整体稳定肌APAs控制机制的调制。     

不同认知负荷汉字输入的眼动研究

采用Tobii1750眼动仪记录不同汉字输入法输入句子材料、单字材料、词组材料时眼动的注视次数、平均注视时间及瞳孔直径的变化,结果发现随认知负荷的加大,注视次数、平均注视时间没有显著变化,瞳孔直径则随认知负荷的增加而缩小.     

Effects of Visual Error Timing on Smooth Pursuit Gain Adaptation in Humans

Smooth pursuit (SP) is one of the precise oculomotor behaviors when tracking a moving object. Adaptation of SP is based on a visual-error driven motor learning process associated with predictable changes in the visual environment. Proper timing of a sensory signal is an important factor for adaptation of fine motor control. In this study, we investigated whether visual error timing affects SP gain adaptation. An adaptive change in SP gain is produced experimentally by repeated trials of a step-ramp tracking with 2 different velocities (double-velocity paradigm). The authors used the double-velocity paradigm where target speed changes 400 or 800 ms after the target onset. The results show that SP gain changed in a certain time window following adaptation. The authors suggest that SP adaptation shown in this study is associated with timing control mechanisms.     

Visual feature vs. conjunction searches as a robust manipulation of perceptual load

It has previously been suggested that Lavie’s Perceptual Load Theory can be assessed using feature vs. conjunction search tasks. In this study we manipulated load using a novel paradigm which retains the key features of both classic Load Theory and Feature Integration Theory paradigms. This new paradigm has the advantage of an inbuilt manipulation check which is necessary for future research to translate Load Theory to applied contexts. Across five experiments, we demonstrate the robust nature of this paradigm, which functions with extended display times, large, complex stimuli and when conditions are intermixed on a trial-by-trial basis. We also rule out dilution as a possible cause of these results. The results of all five experiments provide evidence that the feature vs. conjunction search dichotomy is an effective means of imposing low and high perceptual load while controlling for working memory load.     

Incidental emotions have a greater impact on the logicality of less proficient reasoners

Previous research shows differences in reasoning about emotional and neutral stimuli. A common explanation hypothesised for this effect is that emotion incurs an additional cognitive load. If this is the case, incidental emotion should have a greater impact on the reasoning of less proficient reasoners, and when items are more difficult, because a greater proportion of available cognitive resources must be allocated to the task. We manipulated the emotional value of reasoning stimuli using conditioning and with the simultaneous presentation of images. The deleterious effect of emotion on logicality was greater for less proficient reasoners. There was also some indication that the effect of emotion may be more pronounced for more difficult items. Physiological responses and affective evaluations of the stimuli were similar across groups, irrespective of reasoning proficiency. Results provide some support for the hypothesis that the impact of emotion occurs through increased cognitive load.