The coordination of reaching and grasping in spastic hemiparesis
The coordination of reaching and grasping in spastic hemiparesis
复制标题
DOI：
10.1016/s0167-9457(00)00006-3
复制
发表时间：
2000-05-01
影响因子：
2.1
通讯作者：
Meulenbroek, RGJ
中科院分区：
文献类型：
--
作者：
Steenbergen, B;van Thiel, E;Meulenbroek, RGJ
研究了六名痉挛性偏瘫受试者的伸手和抓握运动的运动学和内在动力学。动作可以用双手一起进行，也可以每只手单独进行，并使用两种目标宽度。正如预期的那样，单手动任务执行中存在较大的手动不对称性。这些不对称性在抓握时比在伸手时更明显，这是因为在抓握时，受损的手在举起物体之前在零速度下停留的时间更长。这意味着协调更远端的运动组件（手和手指）有困难。此外，受损的手通过以下方式实现了运动目标：(1) 关节运动角度范围减小；(2) 躯干参与增加。关于内在动力学，通过评估位置-时间函数关节对的互相关性来研究肢体内和肢体间的耦合。在效应器空间中，腕部和同侧肩部的位移是相关的，并且在关节角度空间中，分析肘部伸展-肩部屈曲角度对和肘部伸展-肩部仰角对。研究发现，尽管不同对之间耦合紧密，但受损肢体的耦合强度始终较低。这是由于运动的碎片化造成的，主要是由于运动开始时肩膀的大量参与，同时肘部很少或没有伸展。结论是，通过关节对之间的互相关值进行操作的运动碎片是一个重要的变量，通过它可以捕获功能的恢复水平。进一步表明，在双手响应下，未受损的手在许多运动特征上“模仿”了受损的手。在单手和双手运动响应中，受损的手没有改变其运动组织的风格。有人认为，受损手的表面稳定性只能以灵活性下降为代价来维持。最后，肢体间耦合。通过双手切向速度曲线的互相关性进行评估，结果表明在运动过程中该速度很高。 (C) 2000 Elsevier Science B.V. 保留所有权利。 PsycINFO分类：2300；第2330章3250； 3380.
The kinematics and intrinsic dynamics of reaching and grasping movements in six subjects with spastic hemiparesis were studied. Movements were performed with both hands together as well as with each hand in isolation, and two target widths were used. As expected, large manual asymmetries existed in unimanual task performance. These asymmetries were more pronounced for grasping than for reaching, which was a consequence of the fact that in grasping the impaired hand stayed longer at zero velocity before lifting the object. This implies difficulties coordinating the more distal movement component (hand and fingers). In addition, the impaired hand attained the movement goal with (1) decreased angular range of motion of the joints and (2) an increased trunk involvement. With respect to the intrinsic dynamics, intra- and inter-limb coupling was studied by evaluating cross-correlations of position-time functions joint pairs. In effector space the displacement of the wrist and ipsilateral shoulder were correlated, and in joint-angle space the elbow extension-shoulder flexion angle pair and the elbow extension-shoulder elevation angle pair were analysed. It was found that despite tight couplings between the different pairs, the couping strengths for the impaired limb were consistently lower. This was caused by fragmentation of the movement, mainly due to a large shoulder involvement at the start of the movement concurrent with little or no elbow extension. It is concluded that fragmentation of the movement, operationalised by the value of the cross-correlation between joint pairs is an essential variable by which the level of recovery of function can be captured. It was further shown that the unimpaired hand 'mimicked' the impaired hand on a number of movement characteristics under bimanual responding The impaired hand did not change its style of movement organisation among uni- and bimanual movement responding. It is argued that the apparent stability of the impaired hand can only be sustained at the cost of a decreased flexibility. Finally, inter-limb coupling. assessed by means of cross-correlations of the tangential velocity profiles of both hands, was shown to be high during the course of movement. (C) 2000 Elsevier Science B.V. All rights reserved. PsycINFO classification: 2300; 2330; 3250; 3380.