Menrva Research Group, Schools of Mechatronic Systems Engineering and Engineering Science, Simon Fraser University, Metro Vancouver, British Columbia, Canada.
PLoS One. 2019 May 2;14(5):e0216214. doi: 10.1371/journal.pone.0216214. eCollection 2019.
Noisy galvanic vestibular stimulation (nGVS) has been shown to improve dynamic walking stability, affect postural responses, enhance balance in healthy subjects, and influence motor performance in individuals with Parkinson's disease. Although the studies to fully characterize the effect of nGVS are still ongoing, stochastic resonance theory which states that the addition of noisy signal may enhance a weak sensory input signals transmission in a non-linear system may provide a possible explanation for the observed positive effects of nGVS. This study explores the effect of nGVS on fine tracking behavior in healthy subjects. Ten healthy participants performed a computer-based visuomotor task by controlling an object with a joystick to follow an amplitude-modulated signal path while simultaneously receiving a sham or pink noise nGVS. The stimulation was generated to have a zero-mean, linearly detrended 1/f-type power spectrum, Gaussian distribution within 0.1-10 Hz range, and a standard deviation (SD) set to 90% based on each participant's cutaneous threshold value. Results show that simultaneous nGVS delivery statistically improved the tracking performance with a decreased root-mean-squared error of 5.71±6.20% (mean±SD), a decreased time delay of 11.88±9.66% (mean±SD), and an increased signal-to-noise ratio of 2.93% (median, interquartile range (IQR) 3.31%). This study showed evidence that nGVS may be beneficial in improving sensorimotor performance during a fine motor tracking task requiring fine wrist movement in healthy subjects. Further research with a more comprehensive subset of tasks is required to fully characterize the effects of nGVS on fine motor skills.
嘈杂的电前庭刺激（nGVS）已被证明可以改善动态行走稳定性，影响姿势反应，增强健康受试者的平衡，并影响帕金森病患者的运动表现。尽管仍在进行充分描述 nGVS 影响的研究，但随机共振理论表明，添加嘈杂信号可能会增强非线性系统中弱感觉输入信号的传输，这可能为 nGVS 的观察到的积极影响提供了一种可能的解释。本研究探讨了 nGVS 对健康受试者精细跟踪行为的影响。10 名健康参与者通过操纵操纵杆控制物体，以跟随幅度调制信号路径，同时接受假或粉红噪声 nGVS，完成基于计算机的视觉运动任务。刺激产生具有零均值、线性去趋势 1/f 型功率谱、高斯分布在 0.1-10 Hz 范围内，以及基于每个参与者的皮肤阈值设置为 90%的标准偏差（SD）。结果表明，同时进行 nGVS 输送在统计上改善了跟踪性能，使均方根误差降低了 5.71±6.20%（平均值±标准差），使时间延迟降低了 11.88±9.66%（平均值±标准差），并提高了 2.93%的信噪比（中位数，四分位距（IQR）为 3.31%）。这项研究表明，nGVS 可能有助于改善需要精细手腕运动的精细运动跟踪任务中的感觉运动表现。需要进行更多具有更全面任务子集的研究，以充分描述 nGVS 对精细运动技能的影响。
