網膜における物体と背景の動きの分離
Bence P Olveczky1, Stephen A Baccus, Markus Meister
1Division of Health Sciences and Technology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02138, USA.
Nature
|May 20, 2003
まとめ
脳は,網膜から始まる目の動きから,動く物体を区別する. 特殊な網膜のギャングリア細胞は,差異的運動を検知し,目の漂移でも物体の検出を可能にします.
科学分野:
- 神経科学は神経科学である.
- ビジョン ビジョン 科学 科学
- 計算神経科学とは
背景:
- 静止した場面で動く物体を検知することは,視力にとって極めて重要です.
- 固定された目の動きは網膜の画像の漂移を引き起こし,運動検出を複雑にする.
- 脳は,局所的なシーンの動きと,全局的な眼の動きによる漂移を区別しなければならない.
研究 の 目的:
- グローバル・レチナ画像漂移のなかでの局所的な運動の検出の基礎となる神経機構を調査する.
- 運動検知プロセスは網膜自体から始まるかどうかを判断する.
- 異動の区別を担当する網膜回路をモデル化するために.
主な方法:
- 網膜のギャングリアン細胞から記録する.
- 中心と周囲の動きを変化させる刺激に対する反応を分析する.
- 網膜回路の計算モデルを開発する.
主要な成果:
- 網膜のギャングリア細胞のサブセットは,受容場の中心と周囲の間の微分運動のための選択性を示す.
- この運動感度の差は方向に左右されない.
- 非線形インターニューロンと広場アマクリン細胞を含むモデルは,観測された反応とグローバル運動による抑制を説明します.
結論:
- 運動の検出と分離は,脳の上部部部位だけでなく,網膜から始まります.
- 異なる運動に特化した網膜のギャングリア細胞は,動く物体を効果的に標識し,分離することができます.
- この発見は,目の動きの存在における視覚的知覚の基本的メカニズムを明らかにしています.
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