Jaeger D, Gilman S, Aldridge J W
Department of Neurology, University of Michigan, Ann Arbor 48104-1687, USA.
Brain Res. 1995 Oct 2;694(1-2):111-27. doi: 10.1016/0006-8993(95)00780-t.
We studied changes in basal ganglia neuronal activity associated with reaching movements of the arm in two monkeys. Data were obtained from 427 single neuronal units in putamen, 199 in caudate nucleus, and 216 in globus pallidus with multiwire electrodes allowing simultaneous recordings from multiple neurons. In all structures, changes in activity related to movement occurred most often after the onset of EMG: 43% of tested neurons in the putamen, 32% in the caudate nucleus, and 38% in the globus pallidus. Less frequently, changes began before EMG activation: 20% of neurons in the putamen, 19% in caudate nucleus, and 17% in globus pallidus. In general, these changes in neuronal activity lasted longer than EMG activity associated with reaching. The proportions of neurons activated were significantly larger in the putamen than the caudate nucleus. In the pallidum, the proportions were not statistically different from either the putamen or caudate nucleus, and no significant difference was found between the internal and external pallidal segments. Significant selectivity for movements to different targets was observed in 36% of neurons in the putamen, 28% in the caudate nucleus and 9% in the globus pallidus. The lower proportion in the globus pallidus compared to the striatum was significant (P < 0.002). Clusters of activated neurons were found in the striatum, however, the timing of changes was often different for individual neurons in these clusters. A cross-correlation analysis of the activity of neurons in the clusters revealed no evidence of common inputs, suggesting that striatal neurons in close proximity with neurons showing similar changes in activity are driven by different populations of neurons. In the putamen, the anatomical locations of neurons with changes in activity related to movement execution were on average significantly more posterior and lateral than neurons with changes related to the preparation of movement described earlier. These findings support the view that the putamen and the caudate nucleus contain distinct functional areas. The present studies show that most anatomical regions in both the striatum and pallidum participate in the control of executing reaching movements.
我们研究了两只猴子中与手臂伸展运动相关的基底神经节神经元活动的变化。数据来自壳核中的427个单神经元单位、尾状核中的199个以及苍白球中的216个，使用多线电极可同时记录多个神经元的活动。在所有结构中，与运动相关的活动变化最常发生在肌电图（EMG）开始之后：壳核中43%的测试神经元、尾状核中32%的测试神经元以及苍白球中38%的测试神经元。较少情况下，变化在EMG激活之前就开始了：壳核中20%的神经元、尾状核中19%的神经元以及苍白球中17%的神经元。一般来说，这些神经元活动的变化持续时间比与伸展相关的EMG活动更长。壳核中被激活的神经元比例显著大于尾状核。在苍白球中，该比例与壳核或尾状核相比无统计学差异，并且苍白球内部和外部节段之间也未发现显著差异。在壳核中36%的神经元、尾状核中28%的神经元以及苍白球中9%的神经元中观察到对不同目标运动的显著选择性。苍白球中与纹状体相比比例较低是显著的（P < 0.002）。在纹状体中发现了激活神经元的簇，然而，这些簇中单个神经元变化的时间通常不同。对簇中神经元活动的互相关分析没有发现共同输入的证据，这表明与活动变化相似的神经元紧密相邻的纹状体神经元由不同的神经元群体驱动。在壳核中，与运动执行相关的活动变化的神经元的解剖位置平均比之前描述的与运动准备相关的变化的神经元更靠后和更靠外侧。这些发现支持壳核和尾状核包含不同功能区域的观点。目前的研究表明纹状体和苍白球的大多数解剖区域都参与了伸展运动执行的控制。
