Department of Medical Biophysics, The University of Western Ontario, London, Ontario, N6A 3K7, Canada; Centre for Functional and Metabolic Mapping, Robarts Research Institute, The University of Western Ontario, London, Ontario, N6A 5K8, Canada.
Department of Medical Biophysics, The University of Western Ontario, London, Ontario, N6A 3K7, Canada; Centre for Functional and Metabolic Mapping, Robarts Research Institute, The University of Western Ontario, London, Ontario, N6A 5K8, Canada; Department of Clinical Neurological Sciences, University Hospital, London Health Sciences Centre, London, Ontario, N6A 5A5, Canada.
Behav Brain Res. 2019 Jul 2;366:13-18. doi: 10.1016/j.bbr.2019.03.014. Epub 2019 Mar 6.
Ageing is associated with a decline in motor function that critically interferes with activities of daily living involving manual dexterity. Transcranial direct current stimulation (tDCS) is a form of non-invasive brain stimulation that has been shown to enhance manual dexterity in healthy aging adults. The supplementary motor area (SMA) is involved in motor preparation and bimanual control; therefore, bihemispheric tDCS incorporating the SMA may preferentially enhance bimanual motor movements in healthy older adults. The aim of the current study was to determine if tDCS incorporating SMA could improve manual dexterity in older adults. Twenty-four adults, aged 67-84 participated in this double-blind, randomized, cross over design, pilot study. One group of participants (n = 17) were randomized to receive stimulation or sham on their first visit and received the contrary on their second visit, seven days later. A second group of participants (n = 10) received three consecutive days of tDCS while performing a motor task. Participants performed unimanual and bimanual hand movements while receiving 2 mA of tDCS. The total time for participants to complete three trials of each task was recorded. No significant differences in performance times were observed between single or tri session tDCS and sham conditions. However, tDCS had opposing effects on the motor consolidation of anti-phase and in-phase bimanual tasks. During the tri session paradigm, older adults improved performance learning of antiphase bimanual movements more quickly than inphase bimanual movements, suggesting a different mechanism of action of these two movements.
衰老与运动功能下降有关，这严重干扰了涉及手灵巧度的日常生活活动。经颅直流电刺激（tDCS）是一种非侵入性脑刺激形式，已被证明可以提高健康老年人的手灵巧度。运动准备和双手控制涉及补充运动区（SMA）；因此，包含 SMA 的双半球 tDCS 可能会优先增强健康老年人的双手运动。本研究的目的是确定包含 SMA 的 tDCS 是否可以提高老年人的手灵巧度。24 名年龄在 67-84 岁的成年人参加了这项双盲、随机、交叉设计的初步研究。一组参与者（n=17）随机在第一次就诊时接受刺激或假刺激，七天后在第二次就诊时接受相反的刺激。另一组参与者（n=10）在连续三天的运动任务中接受 tDCS。参与者在接受 2 mA 的 tDCS 时进行单手和双手手部运动。记录参与者完成每个任务的三个试验的总时间。在单或三 sessions tDCS 和假刺激条件之间未观察到性能时间的显著差异。然而，tDCS 对反相和同相双手任务的运动巩固有相反的影响。在三 sessions 范式中，老年人更快地提高了反相双手运动的学习表现，而不是同相双手运动，这表明这两种运动的作用机制不同。
