Evaluation of error-correction learning theories for social learning in an insect

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K19245
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 44:Biology at cellular to organismal levels, and related fields
• Research Institution: Hokkaido University
• Principal Investigator: Mizunami Makoto 北海道大学, 理学研究院, 教授 (30174030)
• Project Period (FY): 2021-07-09 – 2023-03-31
• Keywords: 社会学習 / 予測誤差学習 / ２次条件付け / 昆虫 / オクトパミン / コオロギ / 報酬

Outline of Final Research Achievements

Social learning is found in many animals, but its mechanisms are not understood. We previously showed that a cricket that was trained to observe a conspecific staying at a drinking apparatus exhibited an increased preference for the odor of that drinking apparatus. Here we investigated a hypothesis that this learning is achieved by second-order conditioning (SOC), i.e., by associating conspecifics at a drinking bottle with water reward during group drinking in the rearing stage and then associating an odor with a conspecific in training. Injection of an octopamine receptor antagonist before training or testing impaired the learning or response to the learned odor, as we reported for SOC, thereby supporting the hypothesis. Notably, the SOC hypothesis predicts that octopamine neurons that respond to water in the group-rearing stage also respond to a conspecific in training, without the learner itself drinking water, and such mirror-like activities mediate social learning.

Free Research Field

神経生物学

Academic Significance and Societal Importance of the Research Achievements

多くの動物は他個体の行動から学ぶ社会学習を示すが、その仕組みはよく分かっていない。本研究での薬理的な解析の結果、フタホシコオロギの社会学習が「２次条件付け」によって起こることが示唆された。私達が提案する２次条件付けの神経回路モデルからは、オクトパミンニューロンは自身が水を飲む時に発火するが、他個体が水を飲むのを見た時にも発火すること、その様な「ミラー様の神経活動」が社会学習をもたらすことが予測される。昆虫のニューロンが哺乳類と同様に「ミラー様神経活動」を示し社会学習を実現するという本研究での提案は、大きな注目を集めると期待される。