Understanding neural mechanism of hippocampal time prediction in clinical practice

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K20647
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 90030:Cognitive science-related
• Research Institution: Jichi Medical University
• Principal Investigator: Onuki Yoshiyuki 自治医科大学, 医学部, 助教 (90835993)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: 時間予想 / 海馬

Outline of Final Research Achievements

Prospective time estimation is a cognitive function that predicts the time required for a future event or task. However, the involvement of the hippocampus in this cognitive function has been unclear. In this project, we performed functional magnetic resonance imaging (fMRI) and electrocorticography (ECoG) of human hippocampal activity. In addition, we intervened in hippocampal activity by electrical stimulation via electrodes implanted intracranially in patients with intractable epilepsy, and examined changes in time-estimated behavior before and after surgery in patients undergoing hippocampal transection for epilepsy. As results, we found that hippocampal activity that reflected prospective time estimation, and prospective time estimation was altered by the intervention in the hippocampus. Our results suggest that the hippocampus is responsible for the function of prospective time estimation.

Free Research Field

認知神経科学

Academic Significance and Societal Importance of the Research Achievements

本研究成果から海馬が過去の情報を処理するだけでなく、将来の事象や取り掛かる作業に要する時間の推定する機能もあることが明らかになった。これは海馬が関与する認知機能の従来の知見を拡張するだけでなく、臨床的な意義も非常に大きい成果である。例えば、注意欠陥・多動性障害(ADHD)等の発達障害や海馬が萎縮するアルツハイマー病患者は、時間の見積もりが甘く、日常の適切な時間管理ができない症状が生じる場合がある。これまでは誤った時間見積もりを正す習慣の指導等が主な対症療法であった。本研究の成果から、予想時間評価に支障が出てしまう症状に対して、海馬の機能に着目した新たな診断法や治療法の開発が期待出来る。