Practice Effects on Motor Control in Healthy Seniors and Patients with Mild Cognitive Impairment and Alzheimer's Disease

ABSTRACT

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.     

社会认同与内、外群体态度的关系：群际威胁和群体情绪的中介作用

为探究社会认同、群际威胁和群体情绪如何同时影响内、外群体态度,本研究以中日撞船事件为考察蓝本向天津市431名大学生被试进行调查研究,结果发现：国家认同在认同威胁对两种群体态度的总影响和通过群体愤怒的间接影响中都起到负向的调节作用;群际威胁和群体情绪在社会认同与内、外群体态度之间具有显著中介作用。结论：国家认同在对群体态度的影响中起基础性作用,不同群际威胁与不同群体情绪相对应进而影响群体态度。     

Resurgence of goal-directed actions and habits

This study investigated how goal-directed and habitual behaviors recover after extinction within the context of the resurgence effect, a form of relapse induced by the removal or worsening of alternative reinforcement. Rats were trained to press a target lever with one reinforcer (O1) for either minimal (4) or extended (16) sessions. An extinction test after the completion of O1 devaluation confirmed that minimal and extended training formed goal-directed and habitual behaviors, respectively. Then, pressing an alternative lever was reinforced with a second reinforcer (O2) while the target response was placed on extinction. When O2 was discontinued, the minimally trained target response resurged with goal-directed status as in the extinction test. However, the extinguished habitual behavior in the extensively trained rats did not recover as a habit but instead with goal-directed status, possibly due to the context specificity of habits or the introduction of a new response–reinforcer contingency. The critical finding that reinforcer devaluation consistently led to less resurgence regardless of the amount of acquisition training provides a clinical implication that coupling differential-reinforcement-of-alternative-behavior (DRA) treatments with the devaluation of the associated reinforcer of problematic behavior could effectively diminish its recurrence.     

两例先天性无痛症患者的心理生理特点研究 Ⅱ.对致痛性强刺激的知觉和反应

本工作对两例先天性无痛症患者对于致痛性强刺激的知觉和反应进行了研究(例1女,10岁,例2男,13岁)。对照组为20例正常儿童,性别和年龄均与患儿相匹配。 结果:1),生活中痛:两例患儿均无(包括痛感觉和痛反应)。2)实验性痛:①痛感觉:两例患儿均无;②“痛”反应:例1有“痛”反应(脉搏和呼吸的变化以及行为反应明显,大致与正常儿童相似)。例2无“痛”反应(脉搏和呼吸的变化轻微,无行为反应,与正常儿童不同)。 由结果看来,先天性无痛症患者似乎可分为两种类型:不完全型(如同例1)和完全型(如同例2)。存在有“痛”反应而无痛感觉的无痛症患者。 本工作结果从另一侧面为痛的两成分学说提供了依据。     

As the Flocks Gather: How Religion Affects Voluntary Association Participation

This study investigates the relationship between different dimensions of religiosity and voluntary association participation using data from Queen'sUniversity's 1996 "God and Society in North America" survey. I look at the participatory, devotional, affiliative, and theological dimensions of religiosity and examine how they affect voluntary association participation at three different levels: membership, volunteering, and serving on a committee. The results show that all four religious dimensions have considerable, but distinctive, influences on secular voluntary association participation.     

Messages about sex in the workplace: A content analysis of primetime television

Because television has the potential to shape cultural beliefs about both sexual norms and appropriate workplace behavior, it seems important to examine TV’s portrayal of “sexual etiquette” in the workplace. In a content analysis of two episodes of every primetime comedy aired on all broadcast and cable networks during fall 2000, we coded every sexual remark and behavior made in a workplace scene. Across all networks, 85 percent of programs and one in four workplace interactions contained some type of sexual content. Overall, a viewer is likely to hear eleven sexual remarks and see two to three sexual behaviors in a workplace setting per hour; this jumps to twenty-three remarks and nine behaviors on cable networks. Sexual remarks were mostly explicit, made in an office setting, by White men, and were rarely (1.4%) about sexual harassment or discrimination. Although sexual content in the workplace was generally less common on broadcast than cable networks, a broadcast network (Fox) actually had the highest overall rate, with sexual content in 38 percent of workplace scenes. Given that research suggests that TV teaches youth about sexuality and cultivates sexual attitudes and beliefs consistent with televised portrayals, it is alarming that youth may learn from television that sex in the workplace is not only commonplace, but also to be tolerated and enjoyed.     

柏拉图和亚里士多德的经济伦理思想比较

经济是城邦的基础,德性却是引导经济运行和发展的必要条件,这是柏拉图和亚里士多德的共同点。然而,私有制和公有制是两实现经济与道德和谐关系的不同手段,这种差别在某种意义上是其平等现不同的结果。     

成败情境下不同目标取向学生焦虑的特点

以五、六年级小学生共 2 1 3人为被试 ,采用 3× 2的研究设计 ,考察了在成功和失败情境下三种成就目标取向 (掌握目标取向、成绩接近目标取向和成绩回避目标取向 )的学生焦虑度的差异。结果发现 :(1 )在两种情境下 ,掌握目标取向的学生的焦虑度显著低于其他两组学生 ,而成绩接近目标取向的学生焦虑度与成绩回避目标学生的焦虑度无显著差异 ;(2 )三组学生在失败情境下的焦虑度显著高于成功情境下的焦虑度     

词汇表征和加工理论及其认知神经心理学证据

认知神经心理学为探讨语言心理表征和加工理论提供了新途径 ,使得人们对心理词典结构的认识不断深入细化。研究表明词汇不同性质的信息在表征上相互独立 ,词典系统至少包括语义系统、语音输入词典与语音输出词典、字形输入词典与字形输出词典等模块。本文着重介绍了这一词典系统及其认知神经心理学证据     

浅析心电波形唯一性假说

通过对海量心电图资料的分析，发现每个人的心电图波形绝然不同，均有其自身特点，也即具有唯一性，而同一人的心电波形在出生后至18岁成年前如人的容貌、身高、体重一样变化较大，成年后则相对稳定、基本不变，我们认为心电波形如同其他生物特征一样具有生物特征的显著特点，由此提出心电图心电波形具有唯一性的假说。