棒-円の対極性に基づいた色視のための神経回路
Maximilian Joesch1, Markus Meister2
1Harvard University, 52 Oxford Street, Cambridge, Massachusetts 02138, USA.
Nature
|April 7, 2016
まとめ
研究者達は 新しい色覚回路を発見しました 状の光受容体だけでなく 状の光受容体は 薄暗い光でも色覚に寄与します マウスやヒトの 紫外線緑の経路は 視覚処理の既存のモデルに 異議を唱えます
科学分野:
- 神経科学
- 視覚科学
- 光受容体生物学
背景:
- カラービジョンは通常,明るい光ではコーン光受容体に依存し,薄暗い光ではロッド光受容体が視力を媒介する.
- 現存するモデルでは,ロッド信号は薄暗い光の中でコン信号と統合するが,色視覚には寄与しない.
- 網膜のギャングリア細胞は視覚情報を処理し,色対照反応を示します.
研究 の 目的:
- ネズミで新たに特定された網膜のギャングリア細胞タイプ (JAMBまたはJ-RGC) を調査する.
- JAMB細胞の視覚的反応と基礎回路を特徴付ける.
- この回路が異なる光条件や種で 色彩認識に与える影響を調査する.
主な方法:
- ネズミの特定の網膜のギャングリア細胞タイプ (JAMB/J-RGC) の遺伝子識別が利用されました.
- 異なる光刺激 (紫外線と緑色) に対するこれらの細胞の色対照視覚反応を記録し分析した.
- 棒とコンの両方の光受容体が,異なる光の強度でJAMB細胞応答に与える貢献を調査した.
主要な成果:
- JAMB/J-RGCは,紫外線 (UV) に対してOFF,緑色に対してONと反応する.
- 緑色の光に対するON反応はロッド光受容体から生じ,以前の仮定に異議を唱えた.
- 棒と円の両方が,敵対的な棒と円の信号で,幅広い光の強度で反応に貢献することを示した.
結論:
- JAMB/J-RGCへの棒とコンの入力を含む新しい色視覚回路が発見されました.
- この回路はマウスとヒトの両方に存在し 薄暗い光の中で色の知覚のための新しいメカニズムを提供し "青いシフト"のような現象を潜在的に説明します
- 遺伝的に定義された この経路の特定は 脳の色処理に関する 研究の道を開きます
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