Effects of Transcranial Direct Current Stimulation on Long-term Motor Learning and Retention

Laburpena

Optimizing the teaching-learning process is essential throughout life. Non-invasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) seem to be an option for optimizing the motor learning curve. This thesis aims to study the effects of tDCS on motor learning, including the retention of a motor. The first randomized controlled study explored the effects of applying tDCS before, during, or after motor practice on retention of the practiced skill in 100 participants. After a single session, similar performance changes were observed in all groups, with no significant differences in the choice reaction time task. In the second randomized controlled study, we examined the effects of tDCS on typing performance in 63 participants. Participants performed a structured program of 23 intervention sessions across 3.5-month: 20, 15-min typing practice and 3 evaluations (pre, middle, post). tDCS group performed better motor performance in the rapid learning phase compared to the sham and control groups. However, these differences dissipated from session 11th. In conclusion, tDCS appears to be a safe stimulation method when administered over multiple sessions in healthy young adults but failed to enhance motor skill acquisition and retention compared with a sham control group.