Cell-type- and pathway- specific information processing in the hippocampal formation

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H04656
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Neurophysiology / General neuroscience
• Research Institution: Osaka City University
• Principal Investigator: Kenji Mizuseki 大阪市立大学, 大学院医学研究科, 教授 (80344448)
• Research Collaborator: Aramaki Tomoko
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 海馬 / スパイク伝達 / 細胞種特異的 / 経路特異的 / 情報処理 / オシレーション / 光遺伝学 / 大規模記録

Outline of Final Research Achievements

To understand circuit-level mechanisms of memory, we investigated how interactions between neurons in the hippocampal formation were modified by experience. We found that burst activity affected the spike transmission probability between neurons. Namely, some cell pairs showed facilitated spike transmission and others showed depressed spike transmission by burst firing. Further, we found that distinct areas/layers and cell-types displayed distinct degree of facilitation and depression in spike transmission.
To understand pathway specific information processing in the hippocampal formation, by combining large-scale electrophysiological recording and optogenetics, we developed a novel method to classify recorded neurons based on their target structures in freely behaving animals. Using this method, we obtained preliminary data showing that subicular neurons projecting to distinct brain regions encode distinct information and show distinct modulation by various network oscillations.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

本研究は、電気生理学ならびに光遺伝学の技術を用いて、海馬からどのような情報がどの脳領域へ分配されるかを明らかにする基盤を築いた。さらに、海馬体の神経細胞間の相互作用が経験によってどの様に変化するかを明らかにした。本研究により、記憶に重要であり、認知症で異常が認められることの多い海馬の情報処理を詳しく調べた成果は、認知症の病態を理解し、より優れた治療法を開発するための基盤となることが期待される。