The use of a tool requires its incorporation into the movement: Evidence from stick-pointing in apraxia
The use of a tool requires its incorporation into the movement: Evidence from stick-pointing in apraxia
复制标题
DOI：
10.1016/j.cortex.2007.12.009
复制
发表时间：
2009-04-01
期刊：
影响因子：
3.6
通讯作者：
Roby-Brami, Agnes
中科院分区：
文献类型：
--
作者：
Jacobs, Stephane;Bussel, Bernard;Roby-Brami, Agnes
当使用工具时，代理人必须控制该工具的运动以执行有效的动作。虽然知觉同化的工具已被证明是发生在其使用过程中，纳入一个实现到控制的运动很少受到关注。在这里，我们调查的能力，将一个对象整合到运动协调，和工具的使用之间的关系。研究人员要求因熟悉工具使用而受损的失智症患者用手指或两根不同长度（23和53厘米）的棍子指向位于不同距离处的目标。无失用症的左脑损伤患者作为对照。分析了运动学，特别关注动作的工作点（WP），定义为手指或棍子的尖端。对照组患者在所有条件下产生的运动具有相似的运动学特征，并且用棍子比用手指稍不准确。相比之下，超过一半的失用症（6/10）表现出不同程度的障碍时，用棍棒指向，表现为偏离和低效的运动策略和异常大的错误。鉴于以前的工作在电机控制和运动学，有人认为，这反映了赤字在预期控制WP位于坚持，也就是说，在集成的坚持到运动。我们认为，这种损害可能与动态身体表征过程的功能障碍有关，这需要扩展到包括要使用的工具。未来的发展方向进行了讨论，以进一步表征对象合并和工具使用之间的关系，其相关性的理解失用症和工具使用的神经基础。(C)2008 Elsevier Srl. All rights reserved.
When using a tool, the agent has to control the movement of this implement to perform an efficient action. While perceptual assimilation of a tool has been shown to occur during its use, the incorporation of an implement into the control of movements has received little attention. Here, we investigated the relation between the ability to integrate an object into motor coordination, and tool use. Apraxic patients impaired for familiar tool use were asked to point at targets located at various distances using either their finger, or two sticks of different lengths (23 and 53 cm). Left-brain damaged patients without apraxia participated as controls. Movement kinematics were analysed, with a particular focus on the working point (WP) of the action, defined as the tip of the finger or stick. Control patients produced movements with similar kinematic characteristics in all conditions, and were slightly less accurate with the sticks than with their finger. In contrast, more than half of the apraxics (6/10) showed various degrees of impairment when pointing with the sticks, manifested by deviant and inefficient motor strategies and abnormally large errors. In light of previous work in motor control and kinematics, it is argued that this reflects a deficit in anticipatively controlling a WP located in the stick, that is, in integrating the stick into the movement. We propose that this impairment might be related to dysfunction of the processes involved in dynamic body representation, which needs to be extended to include the tool to be used. Future directions are discussed to further characterize the relation between object incorporation and tool use, and its relevance for understanding apraxia and the neural bases of tool use. (C) 2008 Elsevier Srl. All rights reserved.