Effect of Transcranial Direct Current Stimulation on Learning and Motor Skill in Healthy Older Adults: A Systematic Review

Background and Aging is associated with brain changes and reduction in motor skill acquisi­tion that can limit its functional capacity. One of the effective interventions is using transcranial direct current stimulation (tDCS). The aim of this systematic review was to assess the effect of tDCS on learning and motor skill in healthy older adults.
A literature search for the period of 1995-2016 was performed using PubMed, Google scholar, Science Direct, OVID, PEDro, Cochrane library, and CINAHL databases. Studies investigating the effect of tDCS in different regions of cortex on learning and motor skill parameters in healthy older adults were included. The PEDro quality scale was used to investigate the studies included.
According to the inclusion criteria of the study, seven articles were selected from 97 relevant articles. There were considerable differences among the studies in terms of methodology, outcome measures, sample size, procedure, etc. The results indicated that using tDCS on primary motor cortex and cerebellum regions could significantly improve motor learning and motor skill in older adults. In addition, tDCS in prefrontal, parietal and temporoparietal regions had significant, strong and long-term effects on cognition and working memory in older adults.
It seems that administration of tDCS in different regions of brain as a boosting technique can enhance motor learning, motor skill, and working memory capacity in healthy older adults. This method can control aging learning deficits.