Study of motor cortical circuits for motor learning

2018 Fiscal Year Final Research Report

• Project/Area Number: 15H02350
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Neurophysiology / General neuroscience
• Research Institution: The University of Tokyo
• Principal Investigator: MATSUZAKI Masanori 東京大学, 大学院医学系研究科(医学部), 教授 (50353438)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: ２光子顕微鏡 / カルシウムイメージング / 運動学習 / 大脳皮質運動野 / 大脳基底核 / 小脳 / 視床 / 軸索

Outline of Final Research Achievements

We conducted two-photon calcium imaging of thalamocortical axonal activity in the motor cortex of mice learning a self-initiated lever-pull task. Layer 1 (L1) axons came to exhibit activity at lever-pull initiation and termination, while layer 3 (L3) axons did so at lever-pull initiation. L1 population activity had a sequence structure related to both lever-pull duration and reproducibility. Stimulation of the substantia nigra pars reticulata activated more L1 than L3 axons, whereas deep cerebellar nuclei (DCN) stimulation did the opposite. Lesions to either the dorsal striatum or the DCN impaired motor learning and disrupted temporal dynamics in both layers. Thus, layer-specific thalamocortical signals evolve with the progression of learning, which requires both the basal ganglia and cerebellar activities.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

本研究成果は、脳全体の理解に不可欠な脳領域間ネットワークの視点から運動学習や運動制御のメカニズムの一端を明らかにしたという点で非常に重要であり、パーキンソン病やジストニアなどの運動失調・運動障害疾患の病態理解に将来的に貢献することが期待される。