Middleton F A, Strick P L
Research Service (151S), VA Medical Center, 800 Irving Ave., Syracuse, NY, USA.
Brain Res Brain Res Rev. 2000 Mar;31(2-3):236-50. doi: 10.1016/s0165-0173(99)00040-5.
The traditional view that the basal ganglia and cerebellum are simply involved in the control of movement has been challenged in recent years. One of the pivotal reasons for this reappraisal has been new information about basal ganglia and cerebellar connections with the cerebral cortex. In essence, recent anatomical studies have revealed that these connections are organized into discrete circuits or 'loops'. Rather than serving as a means for widespread cortical areas to gain access to the motor system, these loops reciprocally interconnect a large and diverse set of cerebral cortical areas with the basal ganglia and cerebellum. The properties of neurons within the basal ganglia or cerebellar components of these circuits resembles the properties of neurons within the cortical areas subserved by these loops. For example, neuronal activity within basal ganglia and cerebellar loops with motor areas of the cerebral cortex is highly correlated with parameters of movement, while neuronal activity within basal ganglia and cerebellar loops with areas of the prefrontal cortex is more related to aspects of cognitive function. Thus, individual loops appear to be involved in distinct behavioral functions. Studies of basal ganglia and cerebellar pathology support this conclusion. Damage to the basal ganglia or cerebellar components of circuits with motor areas of cortex leads to motor symptoms, whereas damage of the subcortical components of circuits with non-motor areas of cortex causes higher-order deficits. In this report, we review some of the new anatomical, physiological and behavioral findings that have contributed to a reappraisal of function concerning the basal ganglia and cerebellar loops with the cerebral cortex.
传统观点认为基底神经节和小脑仅参与运动控制，近年来这一观点受到了挑战。此次重新评估的一个关键原因是有关基底神经节和小脑与大脑皮层连接的新信息。从本质上讲，最近的解剖学研究表明，这些连接被组织成离散的回路或“环路”。这些环路并非作为广泛的皮层区域接入运动系统的一种方式，而是将大量不同的大脑皮层区域与基底神经节和小脑相互连接。这些回路中基底神经节或小脑部分内的神经元特性类似于这些环路所服务的皮层区域内的神经元特性。例如，与大脑皮层运动区域相关的基底神经节和小脑环路内的神经元活动与运动参数高度相关，而与前额叶皮层区域相关的基底神经节和小脑环路内的神经元活动则更多地与认知功能方面相关。因此，各个环路似乎参与不同的行为功能。对基底神经节和小脑病理学的研究支持了这一结论。皮层运动区域回路的基底神经节或小脑部分受损会导致运动症状，而皮层非运动区域回路的皮层下部分受损则会导致高级功能缺陷。在本报告中，我们回顾了一些新的解剖学、生理学和行为学发现，这些发现有助于重新评估基底神经节和小脑与大脑皮层环路的功能。
