理学療法ジャーナル58巻7号

2024年07月発行

Close-up 物理療法と運動療法の併用

経皮的迷走神経刺激と運動療法の併用

著者： 横田裕丈¹

所属機関： ¹新潟医療福祉大学リハビリテーション学部理学療法学科

ページ範囲：P.798 - P.802

総論

1．tVNSの概要

　迷走神経において80〜90％を占める求心線維を非侵襲的に刺激する新たな物理療法（脳刺激法）として，経皮的迷走神経刺激（transcutaneous vagus nerve stimulation：tVNS）が注目されている．tVNSのなかでも，迷走神経耳介枝に対して選択的に刺激を行う手法は経皮的耳介迷走神経刺激（transcutaneous auricular vagus nerve stimulation：taVNS），頸部枝に対するものは経皮的頸部迷走神経刺激（transcutaneous cervical vagus nerve stimulation：tcVNS）と呼ばれる．いずれもてんかん発作やうつ症状の抑制，偏頭痛の緩和，自律神経機能や心機能の改善，さらには脳卒中後の運動機能の改善などが報告されている^1,2）．

　迷走神経求心線維からの情報は，延髄の孤束核（nucleus tractus solitarius：NTS）へ入力された後，青斑核（locus coeruleus：LC），縫線核（raphe nucleus）を介して感覚運動野や前頭前皮質，島といったさまざまな皮質領域へ投射する^3）．機能的磁気共鳴画像法（functional magnetic resonance imaging：fMRI）を用いた研究において，taVNSによりこれらの皮質領域の活動が高まることや^4,5），活動に関連する神経伝達物質の脳内濃度が高まること^6）が明らかになっている（図1）．

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