Shi L H, Luo F, Woodward D J, Chang J Y
Department of Physiology and Pharmacology, School of Medicine, Wake Forest University, Winston-Salem, NC 27157, USA.
Exp Brain Res. 2004 Aug;157(3):303-14. doi: 10.1007/s00221-004-1844-y. Epub 2004 Apr 6.
To investigate the role of basal ganglia in locomotion, a multiple-channel, single-unit recording technique was used to record neural activity simultaneously in the dorsal lateral striatum (STR), globus pallidus (GP), subthalamic nucleus (STN) and substantia nigra pars reticulata (SNr) during spontaneous and treadmill locomotion tasks in freely moving rats. Active and quiescent phases appeared alternately in a spontaneous movement session that lasted 60 min. Principal component analysis of the ensemble neural activity from each region revealed a close correlation with spontaneous motor activity. Most of the neurons in these four basal ganglia areas increased their firing rates during the active phase. In the treadmill locomotion task, the firing rates of neurons in all recording areas, especially in the STN, increased significantly during locomotion. In addition, neural responses related to tone cue, initiation and termination of treadmill were observed in a subset of neurons in each basal ganglia region. Detailed video analysis revealed a limb movement related neural firing, predominantly in the STR and the GP, during treadmill walking. However, the proportion of neurons exhibiting limb movement related firing was significantly greater only in the STR. A few neurons in the STR (4.8%) and the GP (3.4%) discharged in an oscillatory pattern during treadmill walking, and the oscillatory frequency was similar to the frequency of the step cycle. This study demonstrates a variety of neural responses in the major basal ganglia regions during spontaneous and forced locomotion. General activation of all major basal ganglia regions during locomotion is more likely to provide a dynamic background for cortical signal processing rather than to directly control precise movements. Implications of these findings in the model of basal ganglia organization are discussed.
为研究基底神经节在运动中的作用，采用多通道单单元记录技术，在自由活动大鼠进行自发运动和跑步机运动任务期间，同时记录背外侧纹状体（STR）、苍白球（GP）、丘脑底核（STN）和黑质网状部（SNr）的神经活动。在持续60分钟的自发运动过程中，活跃期和静止期交替出现。对每个区域的总体神经活动进行主成分分析，发现其与自发运动活动密切相关。这四个基底神经节区域的大多数神经元在活跃期放电频率增加。在跑步机运动任务中，所有记录区域的神经元放电频率在运动期间显著增加，尤其是在丘脑底核。此外，在每个基底神经节区域的一部分神经元中观察到与音调提示、跑步机启动和终止相关的神经反应。详细的视频分析显示，在跑步机行走过程中，主要在纹状体和苍白球中存在与肢体运动相关的神经放电。然而，仅在纹状体中，表现出与肢体运动相关放电的神经元比例显著更高。在跑步机行走过程中，纹状体（4.8%）和苍白球（3.4%）中的少数神经元以振荡模式放电，振荡频率与步周期频率相似。本研究证明了在自发运动和强制运动期间，主要基底神经节区域存在多种神经反应。运动期间所有主要基底神经节区域的普遍激活更有可能为皮层信号处理提供动态背景，而不是直接控制精确运动。讨论了这些发现对基底神经节组织模型的意义。
