マルチトーカースピーチのスピーチ知覚における出席スピーカーの選択的皮質表現

Nima Mesgarani¹, Edward F Chang

¹Departments of Neurological Surgery and Physiology, UCSF Center for Integrative Neuroscience, University of California, San Francisco, California 94143, USA.

Nature

|April 24, 2012

まとめ

人間は騒音の多い環境でも1つの声に集中することができます. 聴覚皮質の脳の活動は,出席した言葉を抽出し,その特徴を再構築し,単語とスピーカーの識別を可能にします.

科学分野:

神経科学は神経科学である.
聴覚知覚とは,聴覚の知覚である.
コグニティブ・サイエンスコグニティブ・サイエンス

背景:

人間は,複数の競合する声の中で,単一のスピーカーに選択的に注意を払うことができます.
複雑な音響環境におけるスピーチ分離と表現の基礎となる神経機構は,依然としてほとんど不明である.

研究の目的:

人間の聴覚皮質が,多発話者シナリオにおいて,どのように聴衆スピーチを表すかを調査する.
神経応答が,知覚と識別に関連する言語特性をコードしているかどうかを判断する.

主な方法:

2つの同時スピーカーによるダイコティックなリスニングタスク中にヒトの皮質からのマルチエレクトロド表面録音.
神経応答からスピーチスペクトログラムの再構築.
参加した単語とスピーカーのアイデンティティをデコードするための分類分析.

主要な成果:

非初等聴覚皮質の皮質集団の反応は,聴衆のスピーカーの顕著なスペクトルおよび時間的特徴をコードします.
再構築されたスピーチスペクトログラムは,背景スピーカーとは関係なく,出席しているスピーカーの特徴を反映します.
分類器は,神経活動から出席した単語とスピーカーのアイデンティティを成功裏にデコードしました.
注意調節神経選択性は,タスクパフォーマンスと相関しています.

結論:

人間の聴覚皮質は,音声入力を被動的に反映するのではなく,主動的に参加されたスピーチの表現を構築します.
神経表現は目標指向であり,聞き手の知覚的目標に関連する情報を優先します.
これらの発見は,選択的聴覚的注意と言語理解のニューラル基盤に光を当てています.

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