Keller Peter E, Ishihara Masami, Prinz Wolfgang
Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstr. 1a, 04103, Leipzig, Germany.
Cogn Process. 2011 Feb;12(1):127-33. doi: 10.1007/s10339-010-0361-0. Epub 2010 Mar 20.
Previous research on sensorimotor synchronization has manipulated the somatosensory information received from the tapping finger to investigate how feedback from an active effector affects temporal coordination. The current study explored the role of feedback from passive body parts in the regulation of spatiotemporal motor control parameters by employing a task that required finger tapping on one's own skin at anatomical locations of varying tactile sensitivity. A motion capture system recorded participants' movements as they synchronized with an auditory pacing signal by tapping with the right index finger on either their left index fingertip (Finger/Finger) or forearm (Finger/Forearm). Results indicated that tap timing was more variable, and movement amplitude was larger and more variable, when tapping on the finger than when tapping on the less sensitive forearm. Finger/Finger tapping may be impaired relative to Finger/Forearm tapping due to ambiguity arising through overlap in neural activity associated with tactile feedback from the active and the passive limb in the former. To compensate, the control system may strengthen the assignment of tap-related feedback to the active finger by generating correlated noise in movement kinematics and tap dynamics.
先前关于感觉运动同步的研究操纵了从敲击手指接收到的体感信息，以研究来自主动效应器的反馈如何影响时间协调。当前的研究通过采用一项任务来探索被动身体部位的反馈在时空运动控制参数调节中的作用，该任务要求在具有不同触觉敏感性的解剖位置上用手指轻敲自己的皮肤。一个动作捕捉系统记录了参与者的动作，他们通过用右手食指轻敲自己的左手食指指尖（手指/手指）或前臂（手指/前臂）与听觉节奏信号同步。结果表明，与轻敲不太敏感的前臂相比，轻敲手指时的敲击时间更具变化性，运动幅度更大且更具变化性。相对于手指/前臂轻敲，手指/手指轻敲可能会受到损害，这是由于前者中与主动和被动肢体的触觉反馈相关的神经活动重叠所产生的模糊性。为了进行补偿，控制系统可能会通过在运动运动学和敲击动力学中生成相关噪声来加强与敲击相关的反馈对主动手指的分配。
