人体における表面皮質領域による,レチノトピク座標における対側空間のマッピング

M I Sereno¹, S Pitzalis, A Martinez

¹Department of Cognitive Science, Department of Radiology, University of California, San Diego, La Jolla, CA 92093-0515, USA.

Science (New York, N.Y.)

|November 10, 2001

まとめ

研究者らは,機能MRIを用いて,ヒトの頭皮質の視覚領域をマッピングした. 視界情報がどのように組織化されているかを示す,上側頭皮質の網膜の地図が発見されました.

科学分野:

神経科学は神経科学である.
認知神経科学とは
人間の脳をマッピングする

背景:

人間の頭上皮質は,視覚処理と空間認識において重要な役割を果たします.
より高いレベルの視覚領域の機能的組織を理解することは,脳の機能をマッピングするために不可欠です.

研究の目的:

人間の頭上皮質内のより高いレベルの視覚領域の内部組織をマッピングする.
この視覚領域の網膜学的な性質を調査するために.

主な方法:

機能性磁気共鳴画像 (fMRI) を用いて脳の活動を観察した.
参加者は,極角が体系的に変化する周辺のターゲットで遅延サッカードタスクを実行しました.
レチノトピクマッピングは,ターゲットの再現検出と予測不可能なターゲットの特異性を含む,異なるタスク条件下で評価されました.

主要な成果:

上頭頭皮質内の特定の領域は,記憶された標的の角度の堅固な網膜学的なマッピングを示した.
観測されたレチノトピクマップは,ターゲットの回転方向が逆転したとき,逆転を示した.
地図は,ターゲットの再出現や予測不可能なターゲットの偏心など,タスクの要求の変動にもかかわらず,安定したままでした.

結論:

上側頭皮質の特定された領域は,網膜の地図と一致する特徴を示しています.
この発見は,このヒトの頭頂部領域内の機能的な組織を示唆しています.
この領域の特性は,マカク類の類人猿に見られる横側内膜内領域 (LIP) と一致し,視覚処理に関する比較的な洞察を提供します.

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