From the Department of Otolaryngology, Faculty of Medicine (S.I., M.K., Y. Yoshifuji, C.F.), and Educational Physiological Laboratory, Graduate School of Education (Y. Yamamoto, F.T.), The University of Tokyo, Japan.
Neurology. 2014 Mar 18;82(11):969-75. doi: 10.1212/WNL.0000000000000215. Epub 2014 Feb 14.
To examine the effect of an imperceptible level of galvanic vestibular stimulation (GVS), delivered as zero-mean current noise (noisy GVS), on postural performance in healthy subjects as well as in patients with bilateral peripheral vestibular dysfunction.
White noise GVS with an amplitude ranging from 0 to 1,000 μA was applied in 21 healthy subjects and 11 patients with bilateral vestibular dysfunction. Two-legged stance tasks were performed with the eyes closed during a 60-second period, which consisted of a baseline period without stimulation and a stimulation period with GVS. We examined 3 parameters: the velocity, the envelopment area, and the root mean square (RMS) of the center of pressure.
White noise GVS improved all 3 parameters in 76% of healthy subjects. The amplitude of the optimal stimulus was 281 ± 40 μA, and it improved the velocity, area, and RMS by 18.4% ± 2%, 37.9% ± 3.5%, and 20.4% ± 2.2%, respectively (p < 0.01). The GVS improved all 3 parameters in 91% of patients. The amplitude of the optimal stimulus was 456 ± 82 μA, and it improved the velocity, area, and RMS by 29.4% ± 4.9%, 45.6% ± 4.7%, and 22% ± 3.3%, respectively (p < 0.01).
Noisy GVS is effective in improving postural stability in healthy subjects as well as in patients with bilateral vestibular dysfunction.
This study provides Class IV evidence that in patients with bilateral vestibular dysfunction, an imperceptible level of noisy GVS may improve postural stability.
研究一种微电流（零均值电流噪声）形式的电前庭刺激（GVS）对健康受试者及双侧周围性前庭功能障碍患者的姿势表现的影响。
21 名健康受试者和 11 名双侧前庭功能障碍患者接受了幅度在 0 至 1000 μA 之间的白噪声 GVS 刺激。在 60 秒的闭眼双足站立任务期间，进行了无刺激的基线期和有 GVS 刺激的刺激期。我们检查了 3 个参数：中心压力的速度、包络面积和均方根（RMS）。
白噪声 GVS 改善了 76%健康受试者的所有 3 个参数。最佳刺激的幅度为 281 ± 40 μA，它分别提高了速度、面积和 RMS 18.4% ± 2%、37.9% ± 3.5%和 20.4% ± 2.2%（p < 0.01）。GVS 改善了 91%患者的所有 3 个参数。最佳刺激的幅度为 456 ± 82 μA，它分别提高了速度、面积和 RMS 29.4% ± 4.9%、45.6% ± 4.7%和 22% ± 3.3%（p < 0.01）。
噪声 GVS 有效改善了健康受试者及双侧前庭功能障碍患者的姿势稳定性。
本研究提供了 IV 级证据，表明在双侧前庭功能障碍患者中，一种微电流的噪声 GVS 可能改善姿势稳定性。
