BRAIN and NERVE－神経研究の進歩63巻9号

2011年09月発行

総説

痛みと痒みの脳内認知機構

著者： 柿木隆介¹² 望月秀紀¹²

所属機関： ¹自然科学研究機構生理学研究所統合生理研究系感覚運動調節研究部門 ²総合研究大学院大学生命科学研究科生理科学専攻

ページ範囲：P.987 - P.994

文献概要

はじめに

　ヒト脳内での痛みと痒みの認知機構の研究は，極めて重要なテーマであるにもかかわらず，種々の技術的困難のために遅々として進まなかった。ヒトを対象とする場合，非侵襲的検査を用いなければならないことが最大の理由である。しかし，近年の科学技術の急速な進歩によって，従来から行われてきた脳波に加え，ポジトロン断層撮影（positron emission tomography：PET），機能的磁気共鳴画像（functional magnetic resonance imaging：fMRI）および脳磁図を用いた研究発表が増加してきた。脳磁図は時間分解能が高いため初期反応の時間的情報を得るのに適しており，fMRIは空間分解能が高いため詳細な活動部位の解析に適している^1,2)。本稿では，痛みと痒みに分けて，それらに関連した脳活動について脳磁図とfMRIを用いた筆者らの最近の研究成果を紹介したい。

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