The role of the basal ganglia and limbic system for decision making under a social context.

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K01955
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Basic / Social brain science
• Research Institution: National Institute of Information and Communications Technology (2017-2018); Tamagawa University (2016)
• Principal Investigator: Enomoto Kazuki 国立研究開発法人情報通信研究機構, 脳情報通信融合研究センター脳情報工学研究室, 研究員 (10585904)
• Co-Investigator(Kenkyū-buntansha): 藤田 一郎 大阪大学, 生命機能研究科, 教授 (60181351)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 大脳基底核 / ドーパミン / 線条体 / 報酬

Outline of Final Research Achievements

In social contexts, assigning long-term values of multiple future rewards to a series of actions is critical for reaching a distant goal. Dopaminergic (DA) neurons in the midbrain are suggested to send a signal of the long-term values to the striatum for learning, while the striatal projection neurons (PANs) are suggested to encode the long-term values for selection and performance of actions. I found that dorsolateral DA neurons encoded the long-term values weighted in short timescale, while ventromedial DA neurons encoded them in long timescale. Activity of PANs were more heterogeneous and mixture of the multiple characteristics. These results suggest that topographical DA signals were not simply transferred to the striatum, maybe because of some other characteristic biological structures embedded in the striatum, such as cortico- and thalamo-striatal inputs under the control of DA signals via distinct receptor subtypes.

Free Research Field

神経科学

Academic Significance and Societal Importance of the Research Achievements

この研究成果は、社会的状況などの長期的な将来予測が必要な環境において適切に振る舞うための神経システムの解明に貢献する。特に、ドーパミン細胞とそれらが情報を送っている大脳辺縁系や大脳基底核が関わる意思決定や行動選択に関わる神経回路の機能理解に寄与する。また、それらの神経機能の不調が原因であろうと考えられる運動障害や、依存症や強迫神経症、不安神経症などの神経疾患の解明に役立つことが期待される。