A Common Optimization Principle for Motor Execution in Healthy Subjects and Parkinsonian Patients
A Common Optimization Principle for Motor Execution in Healthy Subjects and Parkinsonian Patients
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DOI：
10.1523/jneurosci.1482-12.2013
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发表时间：
2013-01-09
影响因子：
5.3
通讯作者：
Desmurget, Michel
中科院分区：
文献类型：
--
作者：
Baraduc, Pierre;Thobois, Stephane;Desmurget, Michel
最近对帕金森氏病（PD）的研究强调，帕金森氏症的运动，虽然运动迟缓，但与健康行为有许多共同的属性。这一观察结果表明，PD中的运动迟缓可能是由于运动动机减少。这一假设可以在最优控制理论的框架中进行测试，该理论解释了健康人体运动的许多特征，同时提供了运动行为与成本/收益权衡之间的联系。这种方法提供了一个机会来解释运动缺陷的PD患者的正常运动控制的计算理论的光。我们研究了14例PD患者双侧丘脑底核刺激和16个年龄匹配的健康对照，并测试是否达到运动在这两组中由类似的规则。一个单一的最佳控制模型占达到运动的健康受试者和PD患者，无论条件下的电刺激（开或关）。在所有受试者中，运动速度的选择被解释为运动信号的预设动态范围的存在。这个范围是特殊的，适用于所有运动，无论其幅度如何。在PD患者中，该动态范围异常狭窄，并与运动迟缓相关。电刺激减少了运动迟缓，并扩大了所有患者的运动范围，但没有将其恢复到正常值。这些结果与运动动机假设一致，表明运动努力的约束优化是健康和PD受试者运动规划（速度选择）和运动生产的主要决定因素。
Recent research on Parkinson's disease (PD) has emphasized that parkinsonian movement, although bradykinetic, shares many attributes with healthy behavior. This observation led to the suggestion that bradykinesia in PD could be due to a reduction in motor motivation. This hypothesis can be tested in the framework of optimal control theory, which accounts for many characteristics of healthy human movement while providing a link between the motor behavior and a cost/benefit trade-off. This approach offers the opportunity to interpret movement deficits of PD patients in the light of a computational theory of normal motor control. We studied 14 PD patients with bilateral subthalamic nucleus (STN) stimulation and 16 age-matched healthy controls, and tested whether reaching movements were governed by similar rules in these two groups. A single optimal control model accounted for the reaching movements of healthy subjects and PD patients, whatever the condition of STN stimulation (on or off). The choice of movement speed was explained in all subjects by the existence of a preset dynamic range for the motor signals. This range was idiosyncratic and applied to all movements regardless of their amplitude. In PD patients this dynamic range was abnormally narrow and correlated with bradykinesia. STN stimulation reduced bradykinesia and widened this range in all patients, but did not restore it to a normal value. These results, consistent with the motor motivation hypothesis, suggest that constrained optimization of motor effort is the main determinant of movement planning (choice of speed) and movement production, in both healthy and PD subjects.