Neural mechanisms of "brain timer"

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K12618
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 90030:Cognitive science-related
• Research Institution: Kindai University
• Principal Investigator: Oshio Kenichi 近畿大学, 医学部, 講師 (30296751)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 時間知覚 / 前頭前野 / 運動前野 / 認知科学

Outline of Final Research Achievements

To investigate neuronal processing for time perception, we examined neuronal activity of macaque monkeys. Subjects were given "time discrimination task using cross-modal sensory stimuli" and "reproduction tasks discriminating between three time durations," while recording single-neuron activity from the prefrontal cortex (PFC) and the premotor cortex (PMC) during task performance. In the PFC, it was found that different groups of neurons, based on sensory modality, are involved in measuring time duration. Rather than indicating the existence of a "central clock for timing”, it suggested the presence of sensory-specific mechanisms for processing temporal information. Additionally, transient neuronal activity was observed in the PFC, implying encoding of temporal information related to time duration and the generation of time durations. In the PMC, activities gradually increasing firing rates were frequently observed, suggesting involvement in time measurement.

Free Research Field

脳科学　神経生理学　認知科学

Academic Significance and Societal Importance of the Research Achievements

先行研究で、前頭前野、運動補足野、運動前野、大脳基底核、頭頂葉、小脳、海馬などの多くの脳領域が時間知覚において何らかの形で関与していることが分かっているが、具体的にどのような役割を担っているのかは分かっていない。本課題では、ニューロンの詳細な活動を計測できる単一ユニットレコーディグ法により、時間知覚における前頭前野と運動前野の役割の一端を明らかにした。時間知覚は多くの認知活動とも関わりが深い。また、精神疾患によって時間感覚が歪むことも知られており、時間知覚を診断に役立てようとする試みもある。脳内ストップウォッチの神経基盤の解明は、認知機能の理解に止まらず、臨床応用にも役立つと確信している。