Department of Physical Therapy, Graduate School of Health Sciences, Yamagata Prefectural University of Health Sciences, 260 Kamiyanagi, Yamagata-shi, Yamagata, 990-2212, Japan.
Faculty of Rehabilitation, School of Health Sciences, Fujita Health University, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake-shi, Aichi, 470-1192, Japan.
Cerebellum. 2021 Apr;20(2):203-211. doi: 10.1007/s12311-020-01208-5. Epub 2020 Oct 27.
Cerebellar transcranial direct current stimulation (ctDCS) modulates cerebellar activity and postural control. However, the effects of ctDCS on postural control learning and the mechanisms associated with these effects remain unclear. To examine the effects of single-session ctDCS on postural control learning and cerebellar brain inhibition (CBI) of the primary motor cortex in healthy individuals. In this triple-blind, sham-controlled study, 36 participants were allocated randomly to one of three groups: (1) anodal ctDCS group, (2) cathodal ctDCS group, and (3) sham ctDCS group. ctDCS (2 mA) was applied to the cerebellar brain for 20 min prior to six blocks of standing postural control training (each block consisted of five trials of a 30-s tracking task). CBI and corticospinal excitability of the tibialis anterior muscle were assessed at baseline, immediately after, 1 day after, and 7 days after training. Skill acquisition following training was significantly reduced in both the anodal and cathodal ctDCS groups compared with the sham ctDCS group. Changes in performance measured 1 day after and 7 days after training did not differ among the groups. In the anodal ctDCS group, CBI significantly increased after training, whereas corticospinal excitability decreased. Anodal ctDCS-induced CBI changes were correlated with the learning formation of postural control (r = 0.55, P = 0.04). Single-session anodal and cathodal ctDCS could suppress the skill acquisition of postural control in healthy individuals. The CBI changes induced by anodal ctDCS may affect the learning process of postural control.
小脑经颅直流电刺激（ctDCS）调节小脑活动和姿势控制。然而，ctDCS 对姿势控制学习的影响以及与这些影响相关的机制仍不清楚。本研究旨在探讨单次 ctDCS 对健康个体的姿势控制学习和初级运动皮层小脑脑抑制（CBI）的影响。在这项三盲、假对照研究中，将 36 名参与者随机分配到三个组之一：（1）阳极 ctDCS 组，（2）阴极 ctDCS 组和（3）假 ctDCS 组。在 6 个站立姿势控制训练块（每个块由 5 个 30 秒跟踪任务的试验组成）之前，将 ctDCS（2 mA）施加于小脑脑 20 分钟。在基线、训练后即刻、训练后 1 天和训练后 7 天评估 CBI 和胫骨前肌的皮质脊髓兴奋性。与假 ctDCS 组相比，阳极和阴极 ctDCS 组在训练后姿势控制的技能获得明显降低。训练后 1 天和 7 天后的变化在各组之间没有差异。在阳极 ctDCS 组中，训练后 CBI 显著增加，而皮质脊髓兴奋性降低。阳极 ctDCS 诱导的 CBI 变化与姿势控制的学习形成相关（r = 0.55，P = 0.04）。单次阳极和阴极 ctDCS 可抑制健康个体的姿势控制技能获得。阳极 ctDCS 诱导的 CBI 变化可能影响姿势控制的学习过程。
