Unperceivable noise to active light touch effects onfast postural sway
Unperceivable noise to active light touch effects onfast postural sway
复制标题
主动光触摸对快速姿势摇摆产生难以察觉的噪音
DOI：
10.1016/j.neulet.2011.10.058
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发表时间：
2012
影响因子：
2.5
通讯作者：
T.Moritani
中科院分区：
文献类型：
--
作者：
T.Kimura;M.Kouzaki;K.Masani;T.Moritani
当指尖轻轻触摸稳定的表面时，人体在安静站立时的姿势摆动会减少。来自指尖的触觉反馈信息被认为是造成这种轻触摸效果的原因。研究表明，对感觉系统进行类似噪音的微小刺激可以提高系统对微弱信号的检测能力。在目前的研究中，我们调查了指尖上类似噪音的不可感知的振动是否增强了它的触觉，并促进了安静站立时的轻触效果。13名志愿者保持安静站立，同时用食指轻轻触摸触摸面。根据每个受试者的振动触觉阈值(VT)，除了正常的光触摸条件(无振动，0VT)外，还在触摸表面施加幅度低于0.5VT或VT(1.0VT)的类噪音振动。结果表明，0.5VT时足底前后(AP)和内侧(ML)方向的平均压力中心速度(COP)均显著低于0VT和1.0VT(P<0.05)，而1.0VT和0VT之间无显著差异(P&gT；0.05)。COP的频谱分析表明，在0.5VT时，高频波动(1-10 Hz)的功率显著降低(P<；0.05)，而低频摆动(1 Hz以下)的功率没有显著变化(P>；0.05)。这些结果表明，不可感知的类噪音振动可以通过进一步减少快速姿势摆动来促进轻触碰对姿势稳定性的影响。
Human postural sway during quiet standing is reduced when a fingertip lightly touches a stable surface. The tactile feedback information from the fingertip has been considered responsible for this effect of light touch. Studies have shown that a noise-like minute stimulation to the sensory system can improve the system's weak signal detection. In the present study, we investigated whether a noise-like unperceivable vibration on the fingertip enhances its tactile sensation and facilitates the effect of light touch during quiet standing. Thirteen volunteers maintained quiet standing while lightly touching a touch surface with the index fingertip. Based on each subject's vibrotactile threshold (VT), a noise-like vibration was applied to the touch surface at amplitudes under (0.5VT) or at VT (1.0VT), in addition to the normal light touch condition (no vibration, 0VT). The results showed that the mean velocities of the foot center of pressure (CoP) in both the anteroposterior (AP) and mediolateral (ML) directions were significantly reduced at 0.5VT compared to 0VT and 1.0VT (P<0.05), while there was no significant difference between 1.0VT and 0VT (P>0.05). Frequency analysis of CoP revealed that the power of high-frequency fluctuation (1–10Hz) was significantly reduced at 0.5VT (P<0.05), whereas no significant change was observed in that of low-frequency sway (below 1Hz) (P>0.05). These results indicate that an unperceivable noise-like vibration can facilitate the effect of light touch on postural stability, by further reducing fast postural sway.