Evolutionary origin of visual decision making in the vertebrates

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K15855
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 45020:Evolutionary biology-related
• Research Institution: University of Tsukuba
• Principal Investigator: Suzuki Daichi 筑波大学, 生命環境系, 助教 (60866672)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: ヤツメウナギ / 視蓋 / 視覚 / 意思決定

Outline of Final Research Achievements

This study aims to elucidate the evolutionary origin of the vertebrate tectal neurons that control visual decision making. Previous study showed that there are two types of tectal neurons, one project to the brain stem ipsilaterally and the other contralaterally, controlling avoidance and orienting movements, respectively. In this study, we first clarified that the ipsilaterally brain stem-projecting neurons differentiate during larval stages, while contralaterally brain stem-projecting neurons appear in the metamorphosis. In addition, we also found that an axon guidance molecule receptor gene EphB is specifically expressed in the ipsilaterally brain stem-projecting neurons.

Free Research Field

進化神経行動学

Academic Significance and Societal Importance of the Research Achievements

視覚は他の感覚に比べ、遠距離の状況をすばやく詳細に知ることができることから、適応的な行動を選択する際に果たす役割がきわめて大きく、ヒトの健常な生活においても欠かせない要素である。また、視覚を使った行動の意思決定の中枢である中脳視蓋の神経構造は、ヒトを含めた脊椎動物で広く保存されていることが知られている。したがって本研究の成果は、視覚を使った行動の意思決定の原理の理解に大きな寄与を及ぼすものと考えられる。