Exploration of the role of cortico-basal ganglia loop on cognitive function

2019 Fiscal Year Final Research Report

• Project/Area Number: 19K21205
• Project/Area Number (Other): 18H06082 (2018)
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund (2019); Single-year Grants (2018)
• Review Section: 0704:Neuroscience, brain sciences, and related fields
• Research Institution: Hokkaido University
• Principal Investigator: Suzuki Tomoki 北海道大学, 医学研究院, 助教 (20823355)
• Project Period (FY): 2018-08-24 – 2020-03-31
• Keywords: 大脳基底核 / 視床 / 非ヒト霊長類 / 電気生理 / 眼球運動 / 高次機能

Outline of Final Research Achievements

To explore roles of the cortico-basal ganglia circuits in cognitive functions, we trained non-human primates on the self-timed saccade task, and recorded neuronal signals from the basal ganglia and the thalamus. We found that neural signals in the input structure of the basal ganglia displayed changes just after the instruction of the length of the waiting period in a manner that depended on the length of the period (Suzuki & Tanaka, 2019).
We also found the clear association between neuronal activities during the self-timed task and anti-saccade tasks for individual thalamic neurons. To investigate mechanisms that generate these signals in the thalamus, we assessed roles of cortical input on the activities of the motor thalamus using optogenetic inactivation approach. Many thalamic neurons showed task-specific changes upon light stimulation, suggesting that the cortico-thalamic pathways can be actively involved in computations that are associated with goal-directed behavior.

Free Research Field

システム神経科学

Academic Significance and Societal Importance of the Research Achievements

大脳皮質-基底核情報伝達の調節が皮質-基底核ループ内の運動準備活動を柔軟に変化させることが行動タイミングの変化に貢献している可能性が示唆された。Parkinson病で低周波数帯域活動の異常亢進が観察されるが、これと運動障害との関連の理解にも役立つことが期待される。また、行動タイミングの調節に予期的な行動抑制に関わる神経活動がある程度貢献している可能性があることを示した。こうした神経活動を制御するメカニズムとして、従来考えられている皮質下からの入力の変化に加え、大脳皮質-視床経路の貢献も検討する必要があることが示唆された。