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Background: Transcranial direct current stimulation (tDCS) is a promising tool for improving post-stroke cognitive function. Home-based rehabilitation is increasingly required for patients with stroke, and additional benefits are expected if supplemented with remotely supervised tDCS (RS-tDCS). We evaluated the cognitive improvement effect and feasibility of RS-tDCS in patients with chronic stroke. Methods: Twenty-six patients with chronic stroke and cognitive impairment (Korean version of the Montreal Cognitive Assessment [K-MoCA] score <26) were randomized into real and sham RS-tDCS groups and underwent concurrent computerized cognitive training and RS-tDCS. Patients and caregivers underwent training to ensure correct tDCS self-application, were monitored, and treated 5 d/wk for 4 weeks. We investigated several cognition tests including K-MoCA, Korean version of the Dementia Rating Scale-2, Korean-Boston Naming Test, Trail Making Test, Go/No Go, and Controlled Oral Word Association Test at the end of the training sessions and one month later. Repeated-measures ANOVA was used for comparison between the groups and within each group. The adherence rate of the appropriate RS-tDCS session was also investigated. Results: In within-group comparison, unlike the sham group, the real group showed significant improvement in K-MoCA ( P real =0.004 versus P sham =0.132), particularly in patients with lower baseline K-MoCA (K-MoCA 10–17 ; P real =0.001 versus P sham =0.835, K-MoCA 18–25 ; P real =0.060 versus P sham =0.064) or with left hemispheric lesions (left; P real =0.010 versus P sham =0.454, right; P real =0.106 versus P sham =0.128). In between-group comparison, a significant difference was observed in K-MoCA in the lower baseline K-MoCA subgroup (K-MoCA 10–17 ; P time×group =0.048), but no significant difference was found in other cognitive tests. The adherence rate of successful application of the RS-tDCS was 98.4%, and no serious adverse effects were detected. Conclusions: RS-tDCS is a safe and feasible rehabilitation modality for post-stroke cognitive dysfunction. Specifically, RS-tDCS is effective in patients with moderate cognitive decline. Additionally, these data demonstrate the potential to enhance home-based cognitive training, although significant differences were not consistently found in between-group comparisons; therefore, further larger studies are needed. REGISTRATION: URL: https://cris.nih.go.kr ; Unique identifier: KCT0003427.

Objective This study investigated the effects of process-based cognitive training that targets working memory and cognitive control on memory improvement in healthy elderly individuals and patients with mild cognitive impairment (MCI).Methods Forty healthy subjects and 40 patients with MCI were randomly assigned to either the intervention or control group. The intervention group received 12 sessions of designated cognitive training. The control group did not receive cognitive training. A memory test was administered pre-intervention, post-intervention, and 4 weeks after the intervention. Additional comprehensive neuropsychological tests were also administered including a depression scale questionnaire.Results Performance in attention and working memory, which are directly related to the training domains, and global cognitive function were improved in the intervention group after training. In memory tests, interference by irrelevant stimuli was reduced and recognition memory was improved after the intervention. Furthermore, cognitive training ameliorated depressive symptoms. These training effects were not dependent on MCI status.Conclusion Process-based cognitive training that targets working memory and cognitive control effectively improves memory processes including retrograde interference and recognition, as well as depressive symptoms associated with aging in healthy elderly individuals and patients with MCI.