Changes in Multidigit Synergies and Their Feed-Forward Adjustments in Multiple Sclerosis

The authors explored the changes in multidigit synergies in patients with multiple sclerosis (MS) within the framework of the uncontrolled manifold hypothesis. The specific hypotheses were that both synergy indices and anticipatory synergy adjustments prior to the initiation of a self-paced quick action would be diminished in the patients compared to age-matched controls. The MS patients and age-matched controls (n = 13 in both groups) performed one-finger and multifinger force production tasks involving both accurate steady-state force production and quick force pulses. The patients showed significantly lower maximal finger forces and a tendency toward slower force pulses. Enslaving was increased in MS, but only in the lateral fingers (index and little). Indices of multifinger synergies during steady-state force production were lower in MS, mainly due to the lower amount of intertrial variance that did not affect total force. Anticipatory synergy adjustments were significantly delayed in MS. The results show that MS leads to significant changes in multidigit synergies and feed-forward adjustments of the synergies prior to a quick action. The authors discuss possible contributions of subcortical structures to the impaired synergic control.     

流动儿童同伴侵害的特点及与内化问题的循环作用关系:一项追踪研究

本研究采用纵向设计,以北京市426名四、五年级流动儿童为被试,进行连续4次的追踪测查,考察流动儿童同伴侵害的特点及其与内化问题的动态相互作用关系。结果发现:(1)打工子弟学校流动儿童的同伴侵害与内化问题水平比公立学校流动儿童高;流动儿童的流动性越大,同伴侵害和内化问题越多。(2)控制了性别、年级、家庭社会经济地位(SES)和流动性后,从T1到T2,同伴侵害与孤独感为相互作用关系,且同伴侵害可以显著预测抑郁,但对社交焦虑的预测作用不显著,而从T2到T4,同伴侵害和3种内化问题的相互作用模式完全一致,即T2时的社交焦虑、抑郁和孤独感显著预测T3的同伴侵害,进而显著预测T4的社交焦虑、抑郁和孤独感。(3)抑郁、孤独感与同伴侵害的循环作用在两类流动儿童中具有较强的稳定性,而在社交焦虑和同伴侵害的模型中,打工子弟学校流动儿童的同伴侵害对社交焦虑的作用比公立学校流动儿童更大。可见,同伴侵害和内化问题呈循环作用关系,未来预防/干预研究可以聚焦于减少流动儿童的同伴侵害或内化问题的角度打破二者的恶性循环,帮助他们建立良好的人际关系,构建良性循环,促进他们的积极发展。     

Young girls' developmental skills in underarm throwing

This paper concerns underarm throwing by girls 7 to 12 years of age. Each movement component by trained and untrained girls in underarm throwing or windmill softball pitching was examined. Movement characteristics of ball release, arm motion, trunk activity, and stepping were analyzed to capture experience- and age-related differences in underarm throwing. A total of 48 young girls participated: 25 untrained (age 9.7 yr.), 14 trained/league (age 10.9 yr.), and 9 trained/formal (10.4 yr.). Performance was videotaped individually and evaluated by three observers. Analyses suggest that, while age did not affect performance, the type of training experience influenced the girls' performance on each of the four movement components. The wrist and trunk were identified as showing the most significant progression with experience. The findings have important implications about changes during acquisition of underarm throwing skills.     

靶子的潜在位置数对辨别任务中返回抑制的影响

摘要在严格控制的条件下,以大学生为被试．采用线索一靶子模式的返回抑制范式．考察了靶子在注视点周边可能出现的位置数与辨别任务中返回抑制的关系。实验结果表明．在辨别任务中靶子的潜在位置数对返回抑制量有影响,随着位置数的增加,返回抑制量减小。该结论为返回抑制的注意性观点提供了新的证据。     

Practice effects on motor control in healthy seniors and patients with mild cognitive impairment and Alzheimer's disease

This research was designed to test the hypothesis that motor practice can enhance the capabilities of motor control in healthy controls (NC) and patients with a diagnosis of probable Alzheimer's disease (AD) and mild cognitive impairment (MCI), and consequently results in better motor performance. Approximately half of the subjects in the NC (n = 31), AD (n = 28), and MCI (n = 29) either received or did not receive practice on a task of fast and accurate arm movement with a digitizer. Changes in movement time (MT), movement smoothness (jerk), and percentage of primary submovement (PPS) were recorded and compared among the three groups across six blocks of trials (baseline and five training sessions). For all subjects, practice improved motor functions as reflected by faster and smoother motor execution, as well as a greater proportion of programming control. Compared to unaffected matched controls, AD and MCI subjects exhibited a greater reduction in movement jerk due to practice. Movement time and PPS data revealed that motor practice appeared to reduce the use of "on-line" correction adopted by the AD or MCI patients while performing the aiming movements. Evidently, their arm movements were quicker, smoother, and temporally more consistent than their untrained peers. The findings of this study shed light on how MCI and AD may affect motor control mechanisms, and suggest possible therapeutic interventions aimed at improving motor functioning in these impaired individuals.     

Studying suicide with psychological autopsy: social and cultural feasibilities of the methodology in China

As China opens its door to the world, suicide research is making rapid progress using methods and instruments developed in the West. This is a feasibility study of the psychological autopsy methodology applied in China, with its emphasis on the social and cultural environments. With samples of 66 completed suicides and 66 community normal living controls, the authors found that it is feasible to interview at least two informants for each suicide case and each control, between 2 and 6 months after the suicide. With the Chinese-cultivated contacting method of recruiting cases, the refusal rate is nearly zero. The Western-developed methodology per se proved to be valid in the Chinese culture. Ethical considerations in the context of Chinese culture are as important as in the West. Psychological autopsy technique is shown to be an equally applicable method for the study of completed suicides in Chinese culture as it is in the West. Future epidemiological research on Chinese suicide should use the psychological autopsy method to collect data from larger samples in order to increase our understanding of the risk factors for Chinese suicides.     

Self-compassion at work: A self-regulation perspective on its beneficial effects for work performance and wellbeing

The work environment is fraught with complex demands, hardships, and challenges, highlighting the need to approach work with self-compassion each day. We propose that work self-compassion—a mindset of kindness, gentleness, and care toward oneself as an employee—may generate the resources and motivation needed for self-regulation at work. Drawing from integrated self-control theory (ISCT) and theory on self-compassion, we suggest that on days when employees hold a work self-compassionate mindset, they will exhibit greater work performance and wellbeing via enhanced resource capacity and motivation. In an experimental experience sampling study, we found that a work self-compassionate mindset reduced depletion and increased work self-esteem and thereby heightened daily work engagement and daily resilience. Consequently, employees made greater goal progress at work and experienced higher meaning in life. In a supplemental study, we show that state self-compassion at work is associated with unique variance in work outcomes beyond compassion received from coworkers. We discuss theoretical and practical implications for self-compassion in organizational contexts.