Sensorimotor organization of a sustained involuntary movement.
Sensorimotor organization of a sustained involuntary movement.
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DOI：
10.3389/fnbeh.2015.00185
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发表时间：
2015
影响因子：
3
通讯作者：
Haggard P
中科院分区：
文献类型：
--
作者：
De Havas J;Ghosh A;Gomi H;Haggard P
非随意运动共享大部分用于随意运动的运动控制电路，但两者可以很容易区分。 Kohnstamm 现象（持续的用力推动会导致随后不自觉的手臂抬起）是探索自愿和不自愿运动之间差异的有用实验模型。中枢和外围帐户都已被提出，但关于假定的 Kohnstamm 发生器如何响应传入输入知之甚少。我们通过阻止手臂不自觉的向上运动来解决这个问题。阻塞阻止了 Kohnstamm 特征的肌电图上升模式。重要的是，一旦障碍物被移除，肌电图信号就会恢复之前的增加，这表明尽管有外周输入，发电机仍然持续存在。当双侧不自主运动时只有一只手臂受阻时，只有受阻手臂的肌电图信号显示出效果。障碍物释放后，受阻碍的手臂到达与未受阻碍的手臂相同的位置和肌电图水平。与匹配的自愿运动的比较显示，当 Kohnstamm 运动首次接触障碍物时，保留了拉伸反应，并且高估了感知的接触力。我们的研究结果支持对科恩斯塔姆现象的中央和外围混合解释。这种不自主运动的奇怪主观体验与运动意识强烈依赖于效应副本的观点是一致的，但 Kohnstamm 生成器并不产生效应副本。
Involuntary movements share much of the motor control circuitry used for voluntary movement, yet the two can be easily distinguished. The Kohnstamm phenomenon (where a sustained, hard push produces subsequent involuntary arm raising) is a useful experimental model for exploring differences between voluntary and involuntary movement. Both central and peripheral accounts have been proposed, but little is known regarding how the putative Kohnstamm generator responds to afferent input. We addressed this by obstructing the involuntary upward movement of the arm. Obstruction prevented the rising EMG pattern that characterizes the Kohnstamm. Importantly, once the obstruction was removed, the EMG signal resumed its former increase, suggesting a generator that persists despite peripheral input. When only one arm was obstructed during bilateral involuntary movements, only the EMG signal from the obstructed arm showed the effect. Upon release of the obstacle, the obstructed arm reached the same position and EMG level as the unobstructed arm. Comparison to matched voluntary movements revealed a preserved stretch response when a Kohnstamm movement first contacts an obstacle, and also an overestimation of the perceived contact force. Our findings support a hybrid central and peripheral account of the Kohnstamm phenomenon. The strange subjective experience of this involuntary movement is consistent with the view that movement awareness depends strongly on efference copies, but that the Kohnstamm generator does not produces efference copies.