Can transcranial direct current stimulation combined with interactive computerized cognitive training boost cognition and gait performance in older adults with mild cognitive impairment? a randomized controlled trial.

The study planned 40 participants but analysed 21, so it was underpowered and the results could change with a larger sample. There was no tDCS-only group, so the study cannot separate the effect of tDCS alone from tDCS plus Nintendo Switch training. Outcomes were measured only before and after training, so it is unknown whether the walking benefit lasted. All participants could walk at least 10 m unaided, so the findings may not apply to people with more severe mobility problems. The subtraction task performance during dual walking was not recorded, so the study cannot check whether participants prioritized the cognitive task or walking. The electrode size and individual brain differences may have made the stimulation less focused than intended.

Do not read the dual-task walking improvement as proof that tDCS alone works. Both groups received the same Nintendo Switch cognitive training, and the study had no tDCS-only group.