Brain mechanism controlling righty and lefty

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K06851
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 46010:Neuroscience-general-related
• Research Institution: University of Toyama
• Principal Investigator: Takeuchi Yuichi 富山大学, 学術研究部医学系, 助教 (40508884)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 左右性 / 脳の左右差 / 学習 / 感受性期 / 捕食行動 / 魚類

Outline of Final Research Achievements

In this study, I investigated the neuronal mechanism, developmental processes, and molecular genetic basis responsible for the laterality of predatory behavior in scale-eating fish.
The scale-eating fish shows an enhanced preference for the attack direction in response to scale-eating experience. We analyzed the effects of scale-eating experience on the prey fish attack side preferences of juvenile, young, and adult fish. However, as juveniles and young fish gained more experience, they began to attack from the side corresponding to their asymmetric jaw, and eventually 80% of the juveniles and 50% of the young fish acquired a dominant side. On the other hand, the adult fish remained random after repeated experiments, and none of the adult fish acquired an asymmetric jaw shape. This is the first demonstration of the sensitivity phase for acquiring a behavioral laterality during predation, which requires experience with scale-eating in the early stages of development.

Free Research Field

神経行動学

Academic Significance and Societal Importance of the Research Achievements

鳴禽類の歌やヒトの言語は、発達初期に限定された学習により急激に上達する。今回の結果から、魚類の利きも同様に、特定の時期における経験学習に依存して獲得されることが初めて分かった。鱗食魚の利きは非常に明瞭で、それを制御する入力から出力までの脳神経系が想定できる。今後は、利き獲得の感受性期に関わる脳内制御機構を解明したいと考えている。