Birdsong reward system: the relationship between intrinsic and extrinsic motivations

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H01015
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Experimental psychology
• Research Institution: The University of Tokyo
• Principal Investigator: Okanoya Kazuo 東京大学, 大学院総合文化研究科, 教授 (30211121)
• Co-Investigator(Kenkyū-buntansha): 池渕 万季 国立研究開発法人理化学研究所, 脳神経科学研究センター, 研究員 (20398994) ; 関 義正 愛知大学, 文学部, 教授 (50575123) ; 和多 和宏 北海道大学, 理学研究院, 准教授 (70451408)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 鳴禽類 / ドパミン / 発声 / 動機づけ

Outline of Final Research Achievements

The male songbird sings to the female in courtship, and the bird sings to her even alone. The latter is thought to be sustained by intrinsic motivation, but its underlying neural mechanisms are unknown. In this study, we measured neural activity in the midbrain dopaminergic system and basal ganglia to determine how motivation is generated and leads to spontaneous vocalizations. We found a group of cells in the basal ganglia that showed a gradual increase in firing rate starting a few seconds before the onset of vocalization. In contrast, we found cells in the ventral tegmental area and substantia nigra showing a transient increase in neural activity at the onset of vocalization. These results suggest that the midbrain dopaminergic system pulls the final trigger to initiate vocalization.

Free Research Field

実験心理学

Academic Significance and Societal Importance of the Research Achievements

本研究の結果から、鳥が自発的に発声を開始する際に中脳のドパミン神経系が関与することが明らかになった。最近のげっ歯類を用いた研究からも、自発的な歩行やレバー押し行動の開始に中脳ドパミンニューロンが関わることが報告されている。これらより、内発的動機づけに基づく行動を支える神経機構は、哺乳類と鳥類の間で共通していることが示唆された。