Movement sequence-related activity reflecting numerical order of components in supplementary and presupplementary motor areas
Movement sequence-related activity reflecting numerical order of components in supplementary and presupplementary motor areas
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DOI：
10.1152/jn.1998.80.3.1562
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发表时间：
1998-09-01
影响因子：
2.5
通讯作者：
Alexander, GE
中科院分区：
文献类型：
--
作者：
Clower, WT;Alexander, GE
补充运动区（SMA）和前补充运动区（pre-SMA）与运动序列有关，SMA中的神经元已被证明编码序列成分之间的关系顺序（例如，运动X之后是运动Y）。为了确定运动排序的其他方面是否也可能由SMA或前SMA神经元编码，我们分析了从两个区域记录的任务相关活动，并结合一个排序任务，该任务分离了组件的数字顺序（例如，运动X作为第二分量，不管哪个运动在X之前或之后）。序列由八个分量运动构成，每个分量运动由三个空间变量（起点、方向和终点）表征。任务相关的活动记录从56 SMA和63前SMA神经元进行了分类，根据时代（延迟，反应时间和运动时间）和空间变量或组件的运动与它相关联。除了一个实例的任务相关的活动是选择性的空间变量（SV选择性），而不是任何组件的运动本身。在SMA中的110例SV选择性活性中，43例（39%）显示出显著的数字顺序效应。SMA前病变的相应发生率为82/116（71%），显著高于SMA前病变（P < 0.00001）。没有影响的数字顺序之间的手的路径，运动时间，或与任务性能相关的肌电活动是明显的。我们的结论是，SMA和前SMA中的神经元可能会编码组件的数字顺序，至少对于主要由组件排序方面区分的序列来说是这样。
The supplementary motor area (SMA) and presupplementary motor areas (pre-SMA) have been implicated in movement sequencing, and neurons in SMA have been shown to encode what might be termed the relational order among sequence components (e.g., movement X followed by movement Y). To determine whether other aspects of movement sequencing might also be encoded by SMA or pre-SMA neurons, we analyzed task-related activity recorded from both areas in conjunction with a sequencing task that dissociated the numerical order of components (e.g., movement X as the 2nd component, irrespective of which movements precede or follow X). Sequences were constructed from eight component movements, each characterized by three spatial variables (origin, direction, and endpoint). Task-related activity recorded from 56 SMA and 63 pre-SMA neurons was categorized according to both the epoch (delay, reaction time, and movement time) and the spatial variable or component movement with which it was associated. All but one instance of task-related activity was selective for one of the spatial variables (SV-selective) rather than for any of the component movements themselves. Of 110 instances of SV-selective activity in SMA, 43 (39%) showed significant effects of numerical order. The corresponding incidence in pre-SMA, 82 (71%) of 116, was substantially higher (P < 0.00001). No effects of numerical order were evident among the hand paths, movement times, or electromyographic activity associated with task performance. We concluded that neurons in SMA and pre-SMA may encode the numerical order of components, at least for sequences that are distinguished mainly by that aspect of component ordering.