Neural mechanisms generating cerebellar learning signal in the inferior olivary nucleus

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K18394
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Neurophysiology / General neuroscience; Developmental mechanisms and the body works
• Research Institution: Tokyo Metropolitan Institute of Medical Science
• Principal Investigator: ISHIKAWA Takahiro 公益財団法人東京都医学総合研究所, 運動・感覚システム研究分野, 主席研究員 (90595589)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 小脳 / プルキンエ細胞 / 下オリーブ核 / 登上線維

Outline of Final Research Achievements

To investigate how climbing fiber inputs to Purkinje cells (PCs), that is instructive signal in the cerebellum, is generated in the inferior olive, two experiments were performed. First, complex spikes in PCs evoked by sensory stimuli and electrical stimuli to the cerebral motor cortex were recorded in Crus I and Vermis VI. Recordings were performed by electrophysiological technique and calcium imaging. We found that many PCs generate complex spike in response to both stimuli. Second, we performed neuroanatomical experiments to understand why PCs receive climbing fiber input in response to multiple stimuli. As a result, it is confirmed that only a part of the principal olive sends climbing fiber input to PCs in Crus I, and that part of the principal olive receives input from only the parvocellular red nucleus. Therefore, it is assumed that there is a large network in the inferior olive and multiple sensory and motor information is communicated from one neuron to another.

Free Research Field

神経生理学

Academic Significance and Societal Importance of the Research Achievements

登上線維を介した下オリーブ核から小脳への出力は学習信号として働き、小脳の出力を柔軟に変化させることができる。したがって、下オリーブ核における学習信号生成メカニズムを明らかにできれば、その神経情報処理のルールを利用し、外部から人為的に刺激を与えたり、一定の手順を踏むことによって、適切な学習信号の生成を促すことも可能であると考えられる。小脳における学習の効率化や合理化によって、効果的なリハビリ法やトレーニング法の開発につながることが期待される。