Effectiveness of Transcranial Direct Current Stimulation on Cognitive Function: A Pilot Study

Cognitive impairment, which is one of the debilitating consequences of traumatic brain injury (TBI), leads to long-term adverse outcomes that disrupt an individual's participation in daily activities. This study aimed to investigate the effects of combining occupational therapy with transcranial direct current stimulation (tDCS)-a non-invasive and safe electrical method for targeting specific areas of the brain-on the cognitive function of individuals with TBI.

This semi-experimental study utilized convenience sampling, resulting in the inclusion of 24 patients with moderate to severe TBI. We then randomly assigned them to one of two groups: an experimental group (n = 12) or a control group (n = 12). Both groups underwent 10 sessions of daily occupational therapy, but the experimental group also received 20 minutes of tDCS during their occupational therapy sessions. Cognitive functions, such as working memory, divided attention, problem solving, and planning, were assessed using computer-based versions of the Wisconsin Card Sorting Test (WCST), Tower of London, N-back, and Stroop tests at the baseline and the day after the intervention's conclusion. To implement the data analysis phase, we used SPSS Version 27. Depending on the normality of data distribution, either independent samples t-tests or Mann-Whitney U tests were used to compare the outcomes between the experimental and control groups.

After the 10-session intervention, executive functions improved in both groups (P < 0.05). When comparing the groups, the experimental group demonstrated significant improvements in working memory (P = 0.002), planning (P = 0.002), and problem-solving (P = 0.001); however, no significant difference was observed in selective attention (P = 0.310).

The findings suggest that employing tDCS techniques plays a pivotal role in enhancing specific executive functions, such as working memory, problem-solving, and planning, in patients with traumatic brain injuries. tDCS can be considered a complementary treatment option in the rehabilitation of TBI patients.According to the findings, the use of tDCS can improve executive functions, including working memory, problem-solving, and planning, in TBI patients. As a complementary treatment, tDCS can be utilized in the rehabilitation of TBI patients.