The subthalamic nucleus (STN) is theorized to globally suppress movement through connections with downstream basal ganglia structures. Current theories are supported by increased STN activity when subjects withhold an uninitiated action plan, but a critical test of these theories requires studying STN responses when an ongoing action is replaced with an alternative. We perform this test in subjects with Parkinson's disease using an extended reaching task where the movement trajectory changes mid-action. We show that STN activity decreases during action switches, contrary to prevalent theories. Further, beta oscillations in the STN local field potential, which are associated with movement inhibition, do not show increased power or spiking entrainment during switches. We report an inhomogeneous population neural code in STN, with one sub-population encoding movement kinematics and direction and another encoding unexpected action switches. We suggest an elaborate neural code in STN that contributes to planning actions and changing the plans.

中文翻译：

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运动运动学的不同种群代码和人类丘脑底核正在进行的运动变化

丘脑底核 (STN) 被理论化为通过与下游基底神经节结构的连接来全局抑制运动。当前的理论得到了当受试者拒绝执行未启动的行动计划时 STN 活动增加的支持，但对这些理论的批判性测试需要研究当正在进行的行动被替代方案取代时 STN 的反应。我们使用扩展到达任务在帕金森病受试者中执行此测试，其中运动轨迹在动作中途发生变化。我们表明，与流行的理论相反，在动作转换期间 STN 活动会减少。此外，与运动抑制相关的 STN 局部场电位中的 β 振荡在开关期间不会显示增加的功率或尖峰夹带。我们报告了 STN 中的非同质种群神经代码，一个子群编码运动运动学和方向，另一个编码意外的动作开关。我们建议在 STN 中使用一个精心设计的神经代码，它有助于规划行动和改变计划。