Combination Effects of Forced Mild Exercise and GABAB Receptor Agonist on Spatial Learning,Memory, and Motor Activity in Striatum Lesion Rats

Basal ganglia (BG) lesions cause impairments of different mammalian’s movement and cognition behaviors. Motor circuit impairment has a dominant role in the movement disorders. An inhibitory factor in BG is GABA neurotransmitter, which is released from striatum. Lesions in GABAergic neurons could trigger movement and cognition disorders. Previous evidence showed that GABA_B receptor agonist (Baclofen) administration in human improves movement disorders and exercise can improve neurodegenerative and cognitive decline; however, the effects of both Baclofen and mild forced treadmill exercise on movement disorders are not well known. The main objective of this study is to investigate the combined effects of mild forced treadmill exercise and microinjection of Baclofen in the internal Globus Pallidus on striatum lesion-induced impairments of spatial learning and motor activity. We used Morris water maze and open filed tests for studying spatial learning, and motor activity, respectively. Results showed that mild exercise and Baclofen microinjection could not lonely affect the spatial learning, and motor activity impairments while the combination of them could alleviate spatial learning, and motor activity impairments in striatum-lesion animals. Our results suggest that striatum lesion-induced memory and motor activity impairments can improve with combination interaction of GABA_B receptor agonist and exercise training.     

Neuromuscular control in individuals with chronic ankle instability: A comparison of unexpected and expected ankle inversion perturbations during a single leg drop-landing

While neuromuscular control deficits during inversion perturbations in chronic ankle instability (CAI) cohorts are well documented in the literature, anticipatory motor control strategies to inversion perturbations in CAI are largely unknown. The purpose of this study was to examine neuromuscular control and ankle kinematics in individuals with CAI (n = 15) and matched controls (n = 15) during unexpected and expected single leg drop-landings onto a tilted surface rotated 20° in the frontal plane. Muscle activity from 200 ms pre- to post-landing was recorded from the tibialis anterior (TA), medial gastrocnemius (MG), peroneus longus (PL) and peroneus brevis (PB). Mean muscle activity, co-contraction index (CCI), and peroneal latency was analyzed. Ankle inversion angle at initial contact, time to maximum inversion angle, maximum inversion angle and velocity were also assessed. Significantly longer PL latency, less time to maximum inversion and greater maximum inversion angle was found in CAI compared to controls. Regarding landing condition, significantly greater maximum inversion angle, less inversion at initial contact, longer PB latency, less TA activity and frontal plane CCI during the post-landing phase was found during the unexpected perturbation. Prolonged PL latency and altered ankle kinematics suggests reduced frontal plane ankle stabilization in CAI. However, similar motor control strategies were utilized in both groups during the ankle inversion perturbations.     

Older siblings influence younger siblings' motor development

Evidence exists for two competing theories about the effects of having an older sibling on development. Previous research has found that having an older sibling has both advantages and disadvantages for younger siblings' development. This study examined whether and how older siblings influenced the onset of their own younger siblings' motor milestones, a heretofore unstudied developmental domain in the sibling literature. Parents of 51 sibling pairs reported their children's crawling and walking onset dates. In keeping with imitation theories, in families where younger siblings crawled or walked earlier than their own older sibling, they did so significantly earlier. Moreover, in keeping with limited parental resource theories, in families where older siblings crawled or walked earlier than their own younger sibling, they did so significantly earlier. Older siblings did influence younger siblings' motor development, but how they did so may have depended on unique family characteristics. Copyright © 2008 John Wiley & Sons, Ltd.     

内隐序列学习意识的具身机制

内隐序列学习意识已有三类理论如全局工作平台理论、神经可塑性理论、新异刺激理论都忽略了身体感受的关键因素, 难以揭示意识产生的根本原因。具身意识理论和研究发现, 运动/情感镜像神经元系统及与自我、认知控制系统的交互, 是初级/高级意识产生的本源, 但未涉及内隐序列学习规则意识这个对人类学习认知至关重要的领域。内隐序列学习研究实质上已接近揭示其学习机制正是感知觉运动具身学习, 其意识机制很可能是感知觉运动/情感具身意识, 并且其意识加工脑区与具身意识脑区有关键重合。未来研究可采用Granger因果大脑网络技术证明内隐序列学习意识的具身本源, 并考察已有三类意识理论的具身基础, 以及探索意识影响因素的具身机制。     

Parental assessment of early childhood development: biological and social covariates

This study uses data from the National Longitudinal Survey of Children and Youth (N=8605) to investigate the effects of unfavourable birth outcomes and dimensions of the family environment on the development of Canadian children aged 0–47 months. Among children under 24 months of age, it was found that sex of the child, birth order and low birthweight were significant covariates while the familial environment tended to have little influence. However, among children aged 24–47 months, effects of parenting style, social support, and positive social‐structural conditions of the family supplemented the effects of sex of the child and low birthweight. The results suggest that the cumulative effects of a positive family environment begin to occlude the neonatal disadvantages in the first 47 months of life. Copyright © 2003 John Wiley & Sons, Ltd.     

Why might language and motor impairments occur together?

A step‐wise methodology is employed in order to identify common neurological factors underlying motor and language impairments where they occur together. A sample of 15 5–10‐year‐old children with predetermined language impairment was tested comprehensively using the Illinois Test of Psycholinguistic Ability (ITPA) and the Movement Assessment Battery for Children (Movement ABC). On the basis of these tests, only four of the sample were found to have generally poor performance both in psycholinguistic (particularly indexed by problems with visual closure and sound blending) and motor abilities (particularly indexed by manual dexterity problems—bimanual co‐ordination and drawing—and static balance. Further detailed examination of the findings fostered a number of plausible hypotheses to account for this communality. The viability of these different alternatives is discussed. Copyright © 2003 John Wiley & Sons, Ltd.     

幼儿动作发展与动作抑制研究

运用《儿童动作评估检查表》和停止信号任务,通过教师评定和即时行为实验方法,对40名4～6岁幼儿的动作发展水平、动作发展的内部结构、动作抑制的发展趋势和动作抑制与动作一般发展水平之间的关系进行了详细探讨。结果发现,4～6岁幼儿的动作处于一个迅速发展的时期;幼儿在自身与环境的静止或变动情况下,动作发展水平存在不平衡现象,当儿童自身静止并处于静止的环境中时,动作发展水平显著高于儿童自身移动和环境变动状态下的动作水平;男孩与女孩在动作发展的特定条件下存在差异。同时还发现,幼儿的动作反应抑制能力存在明显的年龄发展趋势,随着幼儿年龄的增长,其动作反应抑制能力增强;动作反应抑制能力与一般动作发展水平之间存在显著相关。     

儿童精细动作能力的发展及与其学业成绩的关系

研究了不同精细动作能力的发展、之间的内在联系及其与儿童学业成绩的关系。被试为151名4－8岁儿童以及30名本科生。精细动作能力的测查包括线条填画任务、图形临摹任务以及筷子技能测验。结果发现：（1）不同精细动作能力的发展速度从高到低依次为线条填画能力、图形临摹能力和筷子使用技能;（2）筷子使用技能与线条填画、图形临摹能力都显著相关,线条填画能力和年龄对筷子使用技能具有显著预测作用;（3）不同学业成绩儿童在各类精细动作能力上都存在显著差异。本研究说明,较基本的精细动作能力是复杂工具性技能发展的基础,同时在小学低年级阶段,儿童的精细动作能力与其学习活动之间存在密切联系。     

效应器在动作序列学习中的作用机制探析

动作序列学习是动作技能学习的重要组成部分,其中大部分动作序列学习都有效应器参与。目前有关效应器在动作序列学习中的作用机制存在两种观点：一是依存于效应器的观点,即动作序列技能的获得依附于具体的效应器,不可向其他效应器迁移,其学习的本质是建立反应或肌肉间的联结。二是独立于效应器的观点,即动作序列技能的获得并不依存于具体效应器,某个效应器获得的技能可以向其他效应器迁移,其学习的本质是建立抽象的刺激表征联结。效应器作用机制随练习程度、意识状态及其他条件的不同而有所变化。     

Use of an analogue method to examine children’s appraisals of threat and emotion in response to stressful events

An analogue methodology was used to present a set of realistic, salient stressors to children in grades 3, 5, and 7. Children (N = 146) viewed eight videotaped vignettes depicting interpersonal and non-interpersonal stressors; these were expected to differentially threaten psychological needs for relatedness, competence and autonomy and provoke different emotional reactions. Analyses showed that scenarios portrayed stressors that were commonly experienced by children and evoked a differentiated profile of appraisals and emotions. When tenets of the motivational theory of stress and coping were tested, scenarios more threatening to needs were more distressing, sadness was linked to relatedness and competence threat appraisals, and fear was a more common reaction to parent stressors that involved dyadic conflict. After accounting for threat appraisals and previous experience of stressors, younger children and girls appraised events as more distressing than older children and boys. Future research could use the analogue procedure to focus on children’s development of regulation and coping with stress.