Elucidation of neural mechanism for adapting flexibly to temporally uncertain future rewards

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06892
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 46010:Neuroscience-general-related
• Research Institution: Okinawa Institute of Science and Technology Graduate University
• Principal Investigator: Miyazaki Katsuhiko 沖縄科学技術大学院大学, 神経計算ユニット, グループリーダー (10426570)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: セロトニン / 光遺伝学 / 時間的不確実性 / 報酬待機行動 / 前頭眼窩野 / 内側前頭前野

Outline of Final Research Achievements

We revealed that there is causal relationship between dorsal raphe serotonin neural activity and patience to wait for delayed rewards. In this study, we found that only optogenetic activation of serotonin in the orbitofrontal cortex promoted waiting when the delay time is constant and the timing to obtain rewards was predictable (low timing uncertainty). We also found that activation of serotonin not only in the orbitofrontal cortex but also in the medial prefrontal cortex promoted waiting when the timing to obtain rewards was unpredictable (low timing uncertainty).(with high temporal uncertainty) . This result suggests that the serotonergic system acts on higher brain regions to produce flexible adaptive behaviors to changes in the timing uncertainty of future rewards.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

セロトニンはうつ病や注意欠陥多動性障害などの衝動性を伴う精神疾患と深く関わっていいるが、セロトニン神経活動がどのように神経疾患と関連しているのかについては未だ謎が多い。本研究では、セロトニンが脳の高次領域で異なって働くことが明らかになった。脳の様々な領域でセロトニンがどのように働くかについての知識を増やすことで、将来の医薬品開発等への貢献が期待される。