Home-Based Transcranial Direct Current Stimulation to Enhance Cognition in Stroke

Randomized Controlled Trial

Myoung-Hwan Ko, MD, PhD; Ju-Yul Yoon, MD; Yun-Ju Jo, OTR/L, SLP; Mi-Nam Son, OTR/L; Da-Sol Kim, MD; Gi-Wook Kim, MD, PhD; Yu Hui Won, MD, PhD; Sung-Hee Park, MD, PhD; Jeong-Hwan Seo, MD, PhD; Yun-Hee Kim, MD, PhD


Stroke. 2022;53(10):2992-3001. 

In This Article

Abstract and Introduction


Background: Transcranial direct current stimulation (tDCS) is a promising tool for improving poststroke 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-MoCA10–17; P real=0.001 versus P sham=0.835, K-MoCA18–25; 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-MoCA10–17; P timexgroup=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 poststroke 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.

Graphic Abstract: A graphic abstract is available for this article.


Cognitive dysfunction after stroke is an unfavorable factor for long-term functional independence.[1] tDCS has beneficial effects on neuropsychiatric pathologies, such as Alzheimer dementia, major depressive disorder, and schizophrenia related to cognitive function.[2,3] In addition, reports indicate that tDCS as well as cognitive training (CogTx)[4,5] has positive effects on poststroke sequelae including neglect, depression, and aphasia.[2,6,7] Therefore, beneficial effects of tDCS on cognitive function after stroke can be anticipated.

Recent research has focused on the convenience, feasibility, and effectiveness of telerehabilitation.[8] A study reported that patients with stroke showed a decline in function after discharge from inpatient rehabilitation facilities.[9] Owing to the pressure at rehabilitation institutions to reduce the length of inpatient stays, the rehabilitation treatment environment is frequently changing, and it is difficult to provide a suitable, familiar environment for patients.[10] Furthermore, there are challenges to the continued provision of outpatient CogTx due to limited accessibility in rural areas.[8]

Since in-home computerized cognition treatment is feasible,[11] if patients can safely and appropriately use tDCS at home, the effectiveness of cognitive therapy could be increased. Depending on the degree of supervision and intervention, home-based tDCS can be divided into home-use tDCS, remotely supervised tDCS (RS-tDCS), and remotely controlled tDCS.[12] In home-use tDCS, patients can control the mode or application time themselves and use the device without supervision. In RS-tDCS, patients cannot control the tDCS settings and receive online support from a supervisor to administer duration and intensity. In remotely controlled tDCS, the device is always monitored and only controlled by the supervisor.[12] A certain level of intervention is required to reduce the possibility of misuse and abuse and for optimal application of tDCS.[2,13] Therefore, for efficiency and safety, RS-tDCS may be the most suitable option.

In studies applying home-based rehabilitation with RS-tDCS in patients with multiple sclerosis and Parkinson disease, groups undergoing RS-tDCS plus CogTx showed greater improvements in cognitive function than groups undergoing CogTx alone.[14,15] To date, few studies have investigated the home-based application of tDCS in patients with stroke,[8] and research on its effectiveness and feasibility is needed.

To our knowledge, no studies have investigated the effectiveness of RS-tDCS in improving cognitive function in patients with stroke. In this pilot study, we aimed to explore whether tDCS combined with home-based CogTx has a cognitive-enhancing effect and to investigate the feasibility of RS-tDCS for patients with chronic stroke.