脳刺激が脳卒中後の視覚回復を促進(Brain stimulation improves vision recovery after stroke)

ad

2025-11-17スイス連邦工科大学ローザンヌ校(EPFL)

EPFLの研究チームは、脳卒中後に視野の半分を失う半側空視(hemianopia)患者を対象に、視覚トレーニングと非侵襲的脳刺激「クロス周波数経頭蓋交流電流刺激(cf-tACS)」を組み合わせた治療法を検証した。刺激は一次視覚野(V1)にアルファ波、動きの知覚を担う中側頭領域(MT/V5)にガンマ波を与え、両領域の異常な神経同期を再調整する仕組みである。16名の患者を対象とした試験では、正しい方向の周波数刺激を受けた群の方が視野拡大や動きの認識が有意に改善した。神経画像から、V1–MT間の経路が部分的に残っている患者がより大きな効果を示し、回路の保存度が予後の指標になる可能性も示唆された。研究者は、視覚リハビリにおける脳刺激の新たな応用として期待できると結論づけている。

<関連情報>

半盲の回復を促進する:両脳領域間クロス周波数刺激の力 Boosting hemianopia recovery: the power of interareal cross-frequency brain stimulation

Estelle Raffin, Michele Bevilacqua, Fabienne Windel, Pauline Menoud, Roberto F Salamanca-Giron, Sarah Feroldi, Sarah B Zandvliet, Nicola Ramdass, Laurijn Draaisma, Patrik Vuilleumier …
Brain  Published:17 November 2025
DOI:https://doi.org/10.1093/brain/awaf252

脳刺激が脳卒中後の視覚回復を促進(Brain stimulation improves vision recovery after stroke)

Abstract

Visual field loss is a common consequence of stroke and manifests in approximatively one-third of patients in the chronic stage. Such loss can significantly impact daily life activities, compromising tasks such as reading, navigating or driving. Although slow and labour intensive, evidence suggests that early interventions with tailored rehabilitation programmes might stimulate visual recovery and improve quality of life in stroke survivors.

To enhance the effects of such rehabilitation programmes, we designed a novel, non-invasive, pathway-specific, physiology-inspired cross-frequency brain stimulation protocol, where complex oscillatory signal integration was inferred from phase–amplitude coupling of oscillatory signals between the primary visual cortex and the motion-sensitive medio-temporal area. Sixteen stroke patients were enrolled in a double-blind, randomized, cross-over trial, during which they performed two blocks of 10 daily training sessions of a direction discrimination task, combined with one of the two cross-frequency transcranial alternative brain stimulation (cf-tACS versus control cf-tACS) conditions.

We found that the cf-tACS condition promoting feedforward visual inputs to the medio-temporal area significantly enhanced motion discrimination performance and shifted visual field borders (i.e. through localized enlargement of isopters). Behavioural improvements associated with a change in oscillatory activity within motion processing pathways were proportional to the amount of residual structural fibres along these pathways and perilesional primary visual cortex activity. In sum, we report, for the first time, that cf-tACS, a novel, pathway-specific, physiology-inspired brain stimulation approach, is able to boost the efficacy of perceptual training, restoring visual motion processing and reducing the severity of visual impairments in adult stroke patients.

医療・健康
ad
ad
Follow
ad
タイトルとURLをコピーしました