Understanding the neural mechanisms of unconscious memory

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K18564
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 10:Psychology and related fields
• Research Institution: Jikei University School of Medicine
• Principal Investigator: Watabe Ayako 東京慈恵会医科大学, 医学部, 教授 (00334277)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 情動 / 可塑性 / 脳幹 / 扁桃体 / マウス

Outline of Final Research Achievements

Positive and negative affection is important for animal survival, and research on emotions and memory has been actively conducted worldwide. Previous studies have focused on the unconditioned stimulus signals via highly processed thalamic and cerebral pathways. Here, we have found that parabrachial-to-amygdala pathway functions as unconditioned stimulus and forms an artificial aversive memory. We also found that aversive memory formation is mediated via thalamus-to-amygdala pathway, and inhibitory interneuron is involved in its modulation. Moreover, artificial memories were formed by stimulationg the pathways from parabrachial to hypothalamus and ventral tegmental area. By electrophysiological and behavioral analyses, we identified neuromodulators involved in the memory formation and discovered pathway- and cell type-specific mechanisms. These findings will contribute to the development of the fields of basic medicine and psychology as well as neuroscience.

Free Research Field

神経生理学

Academic Significance and Societal Importance of the Research Achievements

過去の経験を記憶しその後の行動を適応的に調節することは動物の生存に重要である。
情動制御に重要な扁桃体には脳幹からの直接経路と視床や皮質からの間接経路による入力がある。本研究では、直接経路の人工的操作による記憶が通常の恐怖記憶と異なる性質を見出し、皮質からの信号とは異なる制御を受ける可能性が示された。また、視床から扁桃体への経路ではポストシナプスの細胞内シグナル系の関与をあきらかにした。さらに、扁桃体以外の皮質下領域への直接経路による人工的な記憶操作にも成功し、記憶の多階層による制御メカニズム解明に貢献した。将来的には、記憶障害やストレス関連障害などの治療法開発に繋がる可能性も考えられる。