視覚皮質の指向列の進化における普遍性
Matthias Kaschube1, Michael Schnabel, Siegrid Löwel
1Max-Planck-Institute for Dynamics and Self-Organization, Bernstein Center for Computational Neuroscience, Faculty of Physics, Göttingen University, D-37073 Göttingen, Germany. kaschube@princeton.edu
Science (New York, N.Y.)
|November 6, 2010
まとめ
研究者らは,6500万年以上離れた3種の哺乳類の視覚皮質に共通する組織原理を発見した. これは,自己組織が,指向偏好マップのためのニューロン回路の進化を導いたことを示唆している.
科学分野:
- 神経科学は神経科学である.
- 進化生物学の進化生物学について
- コンピュータ生物学 コンピュータ生物学
背景:
- 脳の視覚皮質は,感覚情報を機能的な地図に編成します.
- 視覚野のニューロン回路は,これらの機能的なマップの配置を反映しています.
- 視覚野組織の背後にある進化の原理を理解することは極めて重要です.
研究 の 目的:
- 視覚野のオリエンテーション・プレファレンス・マップの共通の組織原理を調査する.
- 進化の深い差異を持つ種間でこれらの原則を比較する.
- 皮質の発達に対する自己組織化モデルの予測をテストする.
主な方法:
- フレット,ツリーシュラ,ガラゴスにおける指向偏好の機能的地図の分析.
- この3種のマップのレイアウトの比較.
- 抑制的な長距離相互作用による皮質ネットワークの自己組織化の数学モデリング.
主要な成果:
- 共同の組織原理は,研究された種のオリエンテーション・プレファレンス・マップで特定されました.
- 対称性に基づく自己組織モデルは,観察されたニューロン回路のレイアウトを正確に予測します.
- 長期間の相互作用を抑制することは,この発達プロセスにとって非常に重要です.
結論:
- 抑圧的な長距離相互作用によって誘発される自己組織化は,視覚野の発達における基本的原理であるようです.
- 進化は,おそらくこの組織戦略を,オリエンテーション・プレファレンス・マップに保存しています.
- これは,視覚回路のこの側面の単一の共通の進化の経路を示唆しています.
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