Conscious Control Is Associated With Freezing of Mechanical Degrees of Freedom During Motor Learning

This study investigated whether conscious control is associated with freezing of mechanical degrees of freedom during motor learning. Participants practiced a throwing task using either error-strewn or error-reduced practice protocols, which encourage high or low levels of conscious control, respectively. After 24 hr, participants engaged in a series of delayed retention and transfer tests. Furthermore, propensity for conscious control was assessed using participants' ratings and freezing was gauged through movement variability of the throwing arm. Performance was defined by mean radial error. In the error-strewn group, propensity for conscious control was positively associated with both freezing and performance. In the error-reduced group, propensity for conscious control was negatively associated with performance, but not with freezing. These results suggest that conscious control is associated with freezing of mechanical degrees of freedom during motor learning.     

The Effect of Locus of Control on University Students' Mental Health: Possible Mediation through Self-Esteem and Coping

The purpose of this study was to examine the effect of locus of control on university students' mental health and to examine possible mediational roles of self-esteem and coping. A total of 418 university students completed Rotters I-E Scale, Self-liking/self-competence Scale, Endlers Coping with Stressful Situations Scale and Depression, Anxiety and Stress Scale. The results showed that external locus of control, lower self-liking and self-competence, as well as less problem-focused and more emotion-focused coping predict more symptoms of depression, anxiety, and stress in university students. However, mediational analysis revealed that the effect of locus of control was fully mediated by self-esteem and coping, with self-liking and emotion-focused coping being the strongest mediators. Results suggest that beliefs about control affect beliefs about one's self-worth and coping strategies, which in turn can affect one's mental health.     

An examination of lower limb asymmetry in ankle isometric force control

While asymmetries have been observed between the dominant and non-dominant legs, it is unclear whether they have different abilities in isometric force control (IFC). The purpose of this study was to compare ankle IFC between the legs. IFC is important for stabilization rather than object manipulation, and people typically use their non-dominant leg for stabilization tasks. Additionally, studies suggested that a limb can better acquire a motor task when the control mechanism of the task is related to what the limb is specialized for. We hypothesized that the non-dominant leg would better (1) control ankle IFC with speed and accuracy, and (2) acquire an ankle IFC skill through direct learning and transfer of learning. Two participant groups practiced an IFC task using either their dominant or non-dominant ankle. In a virtual environment, subjects moved a cursor to hit 24 targets in a maze by adjusting the direction and magnitude of ankle isometric force with speed (measured by the time required to hit all targets or movement time) and accuracy (number of collisions to a maze wall). Both groups demonstrated similar movement time and accuracy between the dominant and non-dominant limbs before practicing the task. After practice, both groups showed improvement in both variables on both the practiced and non-practiced sides (p < .01), but no between-group difference was detected in the degree of improvement on each side. The ability to control and acquire the IFC skill was similar between the legs, which did not support the brain is lateralized for ankle IFC.     

Of guns and snakes: testing a modern threat superiority effect*

Previous studies suggest that ancient (i.e. evolutionary-based) threats capture attention because human beings possess an inborn module shaped by evolution and dedicated to their detection. An alternative account proposes that a key feature predicting whether a stimulus will capture attention is its relevance rather than its ontology (i.e. phylogenetic or ontogenetic threat). Within this framework, the present research deals with the attentional capture by threats commonly encountered in our urban environment. In two experiments, we investigate the attentional capture by modern threats (i.e. weapons). In Experiment 1, participants responded to a target preceded by a cue, which was a weapon or a non-threatening stimulus. We found a larger cuing effect (faster reaction times to valid vs. invalid trials) with weapons as compared with non-threatening cues. In Experiment 2, modern (e.g. weapons) and ancient threats (e.g. snakes) were pitted against one another as cues to determine which ones preferentially capture attention. Crucially, participants were faster to detect a target preceded by a modern as opposed to an ancient threat, providing initial evidence for a superiority of modern threat. Overall, the present findings appear more consistent with a relevance-based explanation rather than an evolutionary-based explanation of threat detection.     

Do young adults show conceptual knowledge of previous distractors?

Using implicit tests, older adults have been found to retain conceptual knowledge of previously seen task-irrelevant information. While younger adults typically do not show the same effect, evidence from one study [Gopie, N., Craik, F. I. M., & Hasher, L. (2011). A double dissociation of implicit and explicit memory in younger and older adults. Psychological Science, 22, 634–640. doi:10.1177/0956797611403321] suggests otherwise. In that study, young adults showed greater explicit than implicit memory for previous distractors on a word fragment completion task. This was interpreted as evidence for maintaining access to previous conceptual knowledge of the distractors. Here, we report two failures to replicate that original finding, followed by a third study designed to test directly whether young adults use conceptual-level information that was previously irrelevant. Our findings agree with others that young adults show weak to no evidence of conceptual knowledge of previously irrelevant information.     

父母心理控制与对立违抗障碍儿童抑郁和攻击行为的关系:父子依恋和母子依恋的中介效应

采用父母心理控制、亲子依恋、抑郁量表对从北京市、山东省和云南省14所小学筛选出来的246名对立违抗障碍(Oppositional Defiant Disorder,ODD)儿童进行施测,并由被试的班主任填写儿童攻击行为量表,考察父、母心理控制对ODD儿童抑郁和攻击行为的影响,以及父子依恋和母子依恋在其中的中介作用。结果发现:(1)ODD儿童中男生人数更多,且男孩的抑郁和攻击行为更严重;(2)父亲对男孩的心理控制更强,而母亲在对男孩和女孩的心理控制上没有显著差异;(3)父、母心理控制与ODD儿童的父子依恋、母子依恋和抑郁均呈显著相关,但只有父亲心理控制与ODD儿童的攻击行为显著相关;(4)父子依恋在父母心理控制和ODD儿童抑郁之间没有起到显著的中介作用,母子依恋在母亲心理控制和ODD儿童抑郁之间有显著的中介作用。父子依恋和母子依恋在父、母心理控制和ODD儿童攻击行为之间均没有起到显著的中介作用。     

留守妇女与儿童焦虑的代际传递:有调节的中介效应

基于发展系统论和社会提供论构建的有调节的中介模型,对322名留守、323名非留守母子进行为期半年共两次的追踪测查,考察家庭（母亲心理控制）、学校（教师支持）和同伴（朋友支持）系统对焦虑代际传递的影响机制。结果发现：（1）心理控制对留守、非留守母子焦虑的代际传递均起部分中介作用;（2）留守母子焦虑代际传递的中介效应受教师支持的调节,随教师支持水平的提高,中介效应变得不再显著;（3）留守、非留守母子焦虑代际传递的直接效应受朋友支持的调节,随朋友支持水平的提高,直接效应变得不再显著。未来研究可聚焦于母亲、教师、同伴的视角打破留守母子焦虑的代际传递。     

基于Think/No-think范式的动机性遗忘研究:行为与脑机制

想/不想范式(Think/No-think,TNT)是基于go/no-go范式提出来的用于研究动机性遗忘过程的实验范式,主要过程是指个体对于记忆的提取抑制可以导致随后该记忆的遗忘。近年来TNT范式的大量行为学研究都一致性地发现记忆提取抑制可以产生负性控制效应,验证了在实验室情境下对动机性遗忘进行研究的可行性。其中,负性控制效应指的是压抑条件的项目相对于基线条件的项目的回忆量有显著降低。关于动机性遗忘发生的神经机制的探讨已积累了大量的研究证据,总结脑电(EEG)和功能核磁共振(f MRI)两个模态的研究,我们提出了动机性遗忘发生的多模态功能网络模型。最后,在该模型的基础上,我们展望了TNT范式未来的研究方向,其中特别注意到同步EEG-f MRI技术的应用有望为我们揭示出记忆提取抑制导致的动机性遗忘发生的动态过程。     

Investigating Individual Differences in Toddler Search with Mixture Models

Children's performance on cognitive tasks is often described in categorical terms in that a child is described as either passing or failing a test, or knowing or not knowing some concept. We used binomial mixture models to determine whether individual children could be classified as passing or failing two search tasks, the DeLoache model room task and the Berthier et al. door task. The data support categorical classification of the children and suggest that the increase in average proportion correct with age is the result of an increasing proportion of children who can solve the tasks. Performance on the two tasks was concordant, and improving performance could be due to advances in a single psychological ability, such as cognitive control. Copyright © 2014 John Wiley & Sons, Ltd.