Altered Arm-Body Coordination with Triggered Pointing Responses as Influenced by Task Predictability

Abstract

Reaching movements generate reaction forces that affect postural stability, requiring sophisticated coordination between body and arm movement to maintain balance. In voluntary movement, this coordination involves feedforward shifts of posture, and such anticipatory postural muscle activity also accompanies the rapid modulation of an ongoing point to suddenly a shifting target (double-step). However, it is unknown if this early postural activity depends on target-shift predictability and whether arm and body motion are similar coordinated to voluntary movement. Body and arm motion coordination during double-step pointing movements from standing were done under differing conditions of target-shift predictability. In a proportion of trials, the pointing target was displaced, with the predictability of target-shift direction varied between two peripheral targets (target-shift direction known) and two central targets (target-shift direction uncertain). The target jump evoked an adjustment in the arm then body response, opposite to the pointing responses to the initial target. The triggered arm-then-body ordering was consistent across target-shift predictability, although known target-shift direction resulted in closer timing of arm and body onsets. The altered coordination in triggered corrections suggests that the body component in triggered reactions depend on response predictability, showing an altered control of arm and body motion.     

Planned Straight or Biased to Be So? The Influence of Visual Feedback on Reaching Movements

Abstract

Behavioral studies consistently find that subjects move their hand along straight paths despite considerations that suggest reaches should be curved. Literature on this topic makes it clear that the experimentally displayed feedback influences how subjects reach. Could the standard visual feedback, a displayed cursor, explain the lack of path curvature in experimental results? To address this question, we conducted three experiments to examine reach behavior in the absence of the standard visual feedback. In the first experiment, we found significant increases in curvature as visual feedback was progressively extinguished across groups. A second experiment revealed that practiced reaches became curved after the standard visual feedback was removed. A final experiment found that subjects’ reaches made before and after a brief display of visual feedback were similar, indicating a preference for specific curved trajectories. Our results suggest that the consistently straight reaches often observed could be due to a bias to move the displayed cursor straight, which when removed reveal subject-specific preferences for reaches that are often curved.     

Effect of Stroke on Joint Control during Reach-to-Grasp: A Preliminary Study

Abstract

We investigated changes in control of inter-segmental dynamics underlying upper extremity dyscoordination caused by stroke. Individuals with stroke and healthy individuals performed a natural reach-to-grasp movement. Kinetic analysis revealed that both groups rotated the shoulder by muscle torque and used interaction torque to rotate the elbow. However, individuals with stroke used interaction torque less than healthy individuals, actively suppressing a substantial portion of it. This resulted in inefficient use of active control and dyscoordination of the upper extremity. The degree of interaction torque suppression and inefficiency of active control at the elbow positively correlated with stroke severity. The increased interaction torque suppression can be a strategy used by individuals with stroke to compensate for deficient feedforward control of this torque.     

Gender Differences in the Creativity–Academic Achievement Relationship: A Study from China

This study investigated gender differences in the relationship between creativity and academic achievement. A sample of 1082 primary students participated in this study in Beijing, China. Their age ranged between 8 and 15 years old (M = 10.41, SD = 0.99). Students’ creativity was measured by the Chinese version of the Torrance Test of Creative Thinking Figural Form A, and academic achievement was based on students’ self-reported grades of last semester. Results revealed that there was a significantly positive relationship between creativity and academic achievement, ranging from r = .07 to r = .21. Gender differences regarding which aspects of creativity were related to academic achievement were also found. Plausible explanations and implications of the findings in creativity research and education are discussed.     

自我关注重评和情境关注重评情绪调节策略及对随后认知控制的影响

认知重评作为高度适应性的情绪调节策略, 是否消耗随后任务所需的认知资源仍存在争议。以往研究把重评作为单一策略研究, 并未区分重评亚型对这一问题进行探索。本研究采用情绪调节与认知控制结合的任务, 考察自我关注和情境关注两种重评亚型调节情绪的效果, 以及对随后认知控制的影响是否存在差异。结果发现两种重评策略都能有效调节情绪, 但调节效果存在差异。从行为角度看, 与中性刺激相比, 负性刺激会引发更高的负性情绪水平, 对随后冲突任务的认知控制能力更差。进一步从神经机制水平来看, 增加负性情绪可能会进一步消耗随后任务可用的认知资源, 与自我关注重评相比, 采用情境关注重评降低负性情绪后, 对随后冲突任务的认知控制能力更强。说明两种重评亚型并不同质, 不仅在调节情绪的效果上存在差异, 而且会引发不同的认知控制后果; 同时, 负性情绪水平越高, 认知控制能力可能会越差。     

3～4岁幼儿冷热自我调节的发展趋势及性别差异——一项纵向研究

自我调节是个体发展和社会化的重要标志,在学前阶段发展迅速。研究选取白天-黑夜、头脚任务、延迟等待等实验范式,考察219名3岁幼儿一年内（3次测试）冷热自我调节的发展趋势及性别差异。结果表明：（1）二因素模型拟合显著好于单因素模型,冷热两成分中度相关;（2）幼儿的冷自我调节中度稳定,热自我调节中低度稳定;（3）幼儿的抑制控制与延迟等待随年龄增加而提高,女孩的延迟等待提高后保持稳定;（4）整体来看,幼儿的抑制控制和延迟等待存在显著性别差异,但具体来看,女孩的抑制控制仅在早期高于男孩,在延迟等待方面却始终高于男孩。结论：3~4岁女孩的冷热自我调节发展不同步,女孩的“性别优势”只在热自我调节上始终存在。     

父母心理控制与小学生的欺负行为:敌意归因和冷酷无情的作用检验

采用班级整群抽样法选取1847名3~6年级小学生（男生987名;平均年龄10.73±1.16岁）及其家长为被试,采用问卷法考察父母心理控制与小学生欺负行为的关系,同时探讨敌意归因和冷酷无情的中介作用。结果发现：（1）父母心理控制显著正向预测小学生的欺负行为;（2）冷酷无情在父母心理控制与小学生欺负行为间的关系中存在中介作用,敌意归因不发挥中介作用;（3）父母心理控制对小学生欺负行为影响的中介机制不存在显著的性别差异和学段差异。本研究结果表明,冷酷无情是父母心理控制影响小学生欺负行为的重要机制,但敌意归因不是。研究者和实践者应注重对欺负者情感加工能力的关注和干预。     

粗暴养育与青少年学业成绩:有调节的中介分析

以往研究表明消极的养育行为损害青少年学业成绩,但对两者之间的关系机制缺乏探究。本研究通过检验一个有调节的中介模型,考察了父母消极归因情境下努力控制在粗暴养育和青少年学业成绩之间的中介作用。880名初中生作为被试,填写粗暴养育问卷、努力控制分量表、儿童责任归因分量表,并以语文、数学和英语的成绩均值作为学业成绩的指标。结果显示：（1）控制性别、年龄、社会经济地位后,粗暴养育与学业成绩呈显著负相关;（2）努力控制是粗暴养育与学业成绩之间的中介变量;（3）粗暴养育通过努力控制对学业成绩的间接效应受父母消极归因的调节。因此,矫正父母消极的养育行为和归因模式,改善孩子的自控能力,有利于改善其学业成绩。     

主动性人格对小学教师工作满意度的影响:一个有调节的中介模型

该研究探讨了主动性人格与小学教师工作满意度的关系,并提出一个有调节的中介模型,考察个人-工作匹配的中介效应和工作-家庭冲突对该效应的调节效应。研究采用主动性人格量表、个人-工作匹配量表、工作-家庭冲突量表和工作满意度量表对8所小学420名教师进行测查,结果表明：（1）主动性人格对个人-工作匹配和工作满意度均有显著的正向预测作用;（2）个人-工作匹配在主动性人格与工作满意度之间起着中介作用;（3）个人-工作匹配与工作满意度的关系（中介效应的后半段路径）受到工作-家庭冲突的调节,即工作-家庭冲突可以降低个人-工作匹配对工作满意度的正向影响。因此,主动性人格和工作满意度之间存在有调节的中介效应。     

Patterns of agonistic interactions in three species of macaque (Macaca mulatta,M fascicularis,M tonkeana)

Patterns of aggression and response to aggression were studied in three groups of macaques living in semiliberty, each group representing a different species: Macaca mulatta, M fascicularis, and M tonkeana. In Macaca mulatta, intensity of aggression is high (biting is frequent) and symmetry in aggression is low: the aggressee most often flees or submits. In Macaca tonkeana, in contrast, biting is exceptional, aggression is very often bidirectional, and appeasement behaviors are frequently observed. Intermediate patterns are found in Macaca fascicularis with, in addition, especially frequent mild forms of submission. It is argued that relationships exist between intensity of aggression, symmetry in aggression, and development of behaviors controlling aggresssion. Whether balances between these variables are species-specific is discussed.