Neural circuits for switching innate defensive behaviors

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K15925
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 46030:Function of nervous system-related
• Research Institution: The University of Tokyo
• Principal Investigator: MORIKAWA Shota 東京大学, 大学院薬学系研究科(薬学部), 特任研究員 (00855207)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 先天的行動 / カルシウムイメージング / ウイルストレーシング / 扁桃体 / 防御行動 / 不安様行動

Outline of Final Research Achievements

Innate behaviors manifest independently of the animal's learning and experience background, suggesting their dependence on genetically conserved neural circuits. However, the precise underlying mechanism remains unclear. This study used the defensive response of mice to a predator odor as a paradigm for innate behavior, using deep brain calcium imaging and virus tracing to identify the neural circuit for odor-induced defensive behavior. Our results indicate that the amygdalopiriform transition area (AmPir) plays a central role in eliciting flight behavior upon exposure to predator odors. Furthermore, we discovered the involvement of the AmPir in the enhancement of persistent anxiety-like behavior induced by specific odorants, including those associated with predators.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

動物は生まれ持って有する先天的な防御行動と、学習や経験によって獲得した後天的な防御行動を適切に選択することで、生存確立を高めてきた。これらは日々の生活を円滑を進めるための適応行動の基礎となるメカニズムの1つであり、本機構の破綻は不安障害を始めとした情動障害に繋がる可能性が高い。本研究を更に推し進めることで、恐怖や不安、ストレスといった情動処理機構の理解を深めることができる可能性がある。