Cockell D L, Carnahan H, McFadyen B J
Department of Kinesiology, University of Waterloo, Ontario, Canada.
Percept Mot Skills. 1995 Oct;81(2):515-9. doi: 10.1177/003151259508100232.
The purpose of this investigation was to describe the strategies used by individuals when motor systems controlling locomotion and prehension must be used simultaneously to perform a task. Subjects were required to perform five tasks: walk normally, walk and pick up a small object, walk and pick up a large object, pick up a small object from a stationary standing position, and pick up a large object while standing. The grasping and walking movements were videotaped and the frequencies of various behaviors were observed (type of grasp, location of contact with the object, support leg during contact with the object, timing of gaze toward object). Characteristics of the grasp were influenced by object size, not by whether the subject was walking. Gaze was shifted to the object before initiation of reach and this pattern was not influenced by size of the object or movement of the subject. Finally, subjects preferred using an ipsilateral support leg while generating the reach, which is a deviation from normal gait patterns. Findings indicate that the motor control system may be hierarchically organized in such a way that stability of the lower limbs supersedes the control of the movement patterns of an upper limb.
本研究的目的是描述当控制运动和抓握的运动系统必须同时用于执行一项任务时，个体所采用的策略。受试者被要求执行五项任务：正常行走、行走并捡起一个小物体、行走并捡起一个大物体、从静止站立位置捡起一个小物体以及站立时捡起一个大物体。对抓握和行走动作进行录像，并观察各种行为的频率（抓握类型、与物体接触的位置、与物体接触时的支撑腿、看向物体的时间）。抓握的特征受物体大小影响，而非受试者是否在行走。在伸手抓握之前目光会转向物体，且这种模式不受物体大小或受试者运动的影响。最后，受试者在伸手抓握时更喜欢使用同侧支撑腿，这与正常步态模式不同。研究结果表明，运动控制系统可能以一种下肢稳定性优先于上肢运动模式控制的方式进行分层组织。
