コメント "脳皮質の折りたたみ尺度は,ニューロンの数ではなく,表面積と厚さによって普遍的"
1Institute of Sports Science, University of Münster, Horstmarer Landweg 62b, D-48149 Münster, Germany.
Science (New York, N.Y.)
|February 26, 2016
まとめ
大型の哺乳類の脳は 渦巻きで 小型の脳は 滑らかです 灰色の物質の比率と折りたたみ指数に基づいた新しい比例モデルは フラクタル幾何学理論よりもこの違いをよく説明します
科学分野:
- 比較神経解剖学
- 哺乳類の脳進化
背景:
- 脳の皮質の構造は哺乳類の種によって大きく異なります
- 大型の哺乳類は,通常,くねった脳皮質 (gyrified) を表しており,小型の哺乳類は,しばしば滑らかな脳皮質 (lissencephalic) を表している.
- これまでのモデルでは フラクタル幾何学を使って この変化を説明しました
研究 の 目的:
- 哺乳類の脳回転に関する提案されたフラクタル幾何学モデルの説明力を評価する.
- グレーマター比率と折り畳み指数に基づく代替モデルを開発し,テストする.
主な方法:
- 哺乳類の脳構造に関する既存のデータの分析
- フラクタル幾何学の予測と比例モデルを比較する数学モデル.
主要な成果:
- フラクタル幾何学モデルは 影響力のあったが,より単純な比例関係に還元可能であることが判明した.
- 灰色の物質の比率と折り畳み指数を統合した提案されたモデルは,利用可能なデータに優れたフィットを提供しました.
- これは脳の収縮度が この2つの測定可能な要因と 強く結びついていることを示唆しています
結論:
- 灰色の物質の比率と折りたたみ指数の関係は 大型哺乳類と小型の哺乳類の脳の折りたたみにおける違いについて より正確な説明を提供します
- この発見は 脳の表面の折り畳みの基本的なパターンを理解するために 複雑なフラクタル幾何学の必要性を 挑戦しています
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