Fukushima Kikuro, Fukushima Junko, Ito Norie, Takei Hidetoshi, Ikeno Kunihiro, Olley Peter M, Chiba Susumu, Kobayashi Nobuyoshi, Inoue Kiyoharu, Warabi Tateo
Clinical Brain Research Laboratory, Sapporo Yamanoue Hospital.
Rinsho Shinkeigaku. 2012;52(11):1001-5. doi: 10.5692/clinicalneurol.52.1001.
Recent studies implicate the cerebellum in cognitive functions in addition to its well-established roles in motor control and learning. Using a memory-based smooth-pursuit task that separates visual working memory from motor preparation and execution, monkeys were trained to pursue (i.e., go) or not pursue (i.e., no-go), a cued direction, based on the working memory of visual motion-direction and a go/no-go instruction. Task-related neuronal activity was examined in cerebral and cerebellar major smooth-pursuit pathways. Different cerebral and cerebellar areas carried distinctly different signals during memory-based smooth-pursuit. In the cerebellum, prediction-related signals (visual working memory, pursuit selection and movement preparation) were represented in the vermal lobules VI-VII and caudal fastigial nucleus, whereas the floccular region (flocculus and ventral paraflocculus) contained predominantly execution-related signals. This task was applied to patients with cerebellar degeneration and idiopathic Parkinson's disease (PD). None of the PD patients tested exhibited impaired working memory of motion-direction and/or go/no-go selection, but they did show task-specific difficulty in generating an initial smooth-pursuit component, suggesting difficulty in smooth-pursuit preparation. In contrast, most cerebellar patients exhibited impaired visual working memory in addition to difficulty in preparing for and executing smooth-pursuit. These results suggest different roles for the basal ganglia and cerebellum in smooth-pursuit planning.
最近的研究表明，小脑除了在运动控制和学习中发挥既定作用外，还参与认知功能。使用一项基于记忆的平稳跟踪任务，该任务将视觉工作记忆与运动准备和执行区分开来，猴子被训练根据视觉运动方向的工作记忆和“去/不去”指令来跟踪（即“去”）或不跟踪（即“不去”）提示的方向。在大脑和小脑的主要平稳跟踪通路中检查了与任务相关的神经元活动。在基于记忆的平稳跟踪过程中，不同的大脑和小脑区域携带明显不同的信号。在小脑中，与预测相关的信号（视觉工作记忆、跟踪选择和运动准备）出现在蚓部小叶VI-VII和尾侧顶核，而绒球区域（绒球和腹侧旁绒球）主要包含与执行相关的信号。该任务应用于小脑变性和特发性帕金森病（PD）患者。所测试的PD患者均未表现出运动方向的工作记忆和/或“去/不去”选择受损，但他们确实在产生初始平稳跟踪成分方面表现出特定任务的困难，这表明在平稳跟踪准备方面存在困难。相比之下，大多数小脑患者除了在准备和执行平稳跟踪方面存在困难外，还表现出视觉工作记忆受损。这些结果表明基底神经节和小脑在平稳跟踪计划中发挥不同作用。
