Unraveling decision-to-action circuits involved in waiting for delayed rewards

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06882
• 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: University of Yamanashi
• Principal Investigator: Murakami Masayoshi 山梨大学, 大学院総合研究部, 特任助教 (00831025)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 意思決定 / 歩行誘発野 / 神経回路 / 電気生理学 / 光遺伝学

Outline of Final Research Achievements

We aimed at understanding how decision-related activities regulate motor-outputs in decisions regarding whether to keep waiting for delayed rewards or give up waiting.
We first established a behavioral task in which a head-restrained mouse must decide whether to keep waiting for delayed rewards by staying still on a treadmill, or give up waiting by initiating locomotion. Next, we identified a brain region involved in a motor output used in this task, namely, forward locomotion. Optogenetic stimulation of a specific region in the midbrain reliably evoked locomotion, and neural recordings revealed this region contained many locomotion-activated neurons. Finally, we found neurons in several decision-related areas send outputs to this identified locomotor region.
In summary, we identified candidate decision-to-action circuits that involve in decision regarding whether to stay still for delayed rewards or give up waiting by initiating locomotion.

Free Research Field

神経生理学、システムズ神経科学

Academic Significance and Societal Importance of the Research Achievements

動物にとって歩行・走行運動を使って空間を動き回ることは、個体の生存や子孫の繁栄に極めて重要であり、様々なシチュエーションで歩行運動が関わる行動選択を適切に行っていくことは脳の最も重要な機能の一つである。本研究ではこの行動選択に関わる神経回路基盤を同定した。このことは、今後さらに行動選択時の情報処理メカニズムの詳細を明らかにするための礎となると考える。
また、歩行運動はパーキンソン病をはじめとした様々な神経疾患で影響を受ける運動である。歩行運動に関わる神経回路とそこへ神経連絡を持つ脳領域を明らかにした本研究は、これらの神経疾患の新たな治療法の開発に大いに役立つと考える。