Elucidating the role of dopamine neurons in reinforcing behavior to obtain uncertain rewards

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K16895
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 51020:Cognitive and brain science-related
• Research Institution: Kyoto University
• Principal Investigator: Ishino Seiya 京都大学, 医学研究科, 特定助教 (40812227)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: 報酬 / ドーパミン

Outline of Final Research Achievements

In behaviors that often do not succeed at once, such as food seeking and courtship, repeating actions even if it does not go as expected may be advantageous for survival and procreation. However, the neural mechanism underlying the mental state remains unclear. In this study, we measured spiking activities of midbrain dopamine (DA) neurons by electrophysiology with the application of optogenetics, and also measured the DA concentration in the part of the striatum, which is the main projection region of the novel DA neurons, whose activity increases when the expected reward is not obtained. The neural circuitry, composed of the novel DA neurons in VTA projecting to the striatum, can play a role in motivating the next reward-seeking behavior when the expected reward is not obtained.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

本研究によって、学習度合いによる新規ドーパミン細胞の活動の生成過程や行動との関係からその性質が少しずつ明らかになってきた。また、新規ドーパミン細胞は従来型ドーパミン細胞と相補的に働く可能性があり、この2種類のドーパミン細胞の関係性を調べることはドーパミン細胞の根本的役割を解明する重要な鍵となる。さらに研究が進むことにより、ドーパミン機能が深く関わる、ギャンブルなどの依存症全般や統合失調症などの精神疾患の、従来とは異なる角度からの病態の理解や診断、新規ドーパミン細胞を標的とした新規治療法の開発、などの新たな可能性を創造する。