The effect of transcranial alternating current stimulation over the supplementary motor area on bimanual coordination in elderly people

Transcranial alternating current stimulation (tACS) is a non-invasive method that offers a potential solution to reduce the effects of aging on brain function.

The aim of this study was to investigate the effect of offline tACS over the supplementary motor area on bimanual coordination in elderly people.

Thirty-one women aged of 60-75 years were selected as convenience. They were assigned to 2 conditions: tACS and Sham, in random order, with one-week interval between conditions. After pre-test, each participant completed four trials of 5 min using Purdue pegboard task. Concurrently, participants received beta tACS with a current intensity of 1 mA. Immediate retention test, transfer test, and delayed retention tests after 48 hours and 1 week were conducted. A 2(condition) x 4(test) ANOVA with repeated measures was performed on gain scores.

The main effects of condition and test were significant (P<0.0001). The Bonferroni tests revealed the significant improvement of bimanual coordination in the tACS condition compared to the sham condition in all retention and transfer tests (P<0.05).

The findings highlights the potential use of offline beta tACS over the SMA as a modulatory factor for enhancing bimanual coordination in the elderly women.