Department of Otorhinolaryngology, Head and Neck Surgery, Clinical Sciences, Lund University Hospital, Lund, Sweden.
J Vestib Res. 2010;20(6):407-17. doi: 10.3233/VES-2010-0391.
We investigated changes of postural responses to repeated bipolar galvanic vestibular stimulation on 5 consecutive days and once again after 3 months. Subjects consisted of 21 healthy volunteers. Except for the first day did the induced torque variance in response to galvanic vestibular stimulation not decrease within each test session, but there was a major reduction from day to day (p< 0.001) reflecting a continued processing of the postural experience gained during the stimulation. The decreased end level magnitude of postural responses after 5 days was retained after 3 months. The galvanic stimulation failed to induce larger torque variance compared to quiet stance toward the end of the 5 days as well as after 3 months, indicating a down-regulation of a repeated erroneous vestibular stimulation by the postural control system - i.e. sensory reweighting. This argues that a major adaptation effect to galvanic vestibular perturbation takes place after the exposure to the stimulation - similar to the concept of the consolidation process involved in motor learning. This should be considered when repeatedly assessing vestibular function both clinically and in studies. It implies that sensory training involved in rehabilitation from vestibular diseases/deficiencies should be executed with spaced intervals in order to procure more efficient learning processes and in the end, a better function.
我们研究了在 5 天内重复双极电前庭刺激后和 3 个月后姿势反应的变化。受试者由 21 名健康志愿者组成。除了第一天，前庭刺激引起的扭矩方差在每次测试中都没有减少，而是每天都有很大的减少（p<0.001），这反映了在刺激期间获得的姿势体验的持续处理。5 天后，姿势反应的最终水平幅度降低在 3 个月后仍保持不变。与 5 天结束时的安静站立相比，以及 3 个月后相比，电刺激未能引起更大的扭矩方差，这表明姿势控制系统对重复错误的前庭刺激进行了下调，即感觉重新加权。这表明，在接触刺激后，对电前庭刺激的主要适应效应会发生——类似于涉及运动学习的巩固过程的概念。在临床和研究中重复评估前庭功能时，都应该考虑到这一点。这意味着，为了获得更有效的学习过程和最终更好的功能，前庭疾病/缺陷康复中涉及的感觉训练应该间隔进行。
