Increased corticospinal excitability after rest with short term motor performance.

Motor skill performance is associated with early changes in corticospinal excitability (CSE), yet the influence of rest periods surrounding motor activity on these neurophysiological responses remains unclear. This study examined how matched pre- and post-activity rest intervals influence CSE following novel fine motor task performance. Twenty-one healthy adults (18-39 years) participated in a single-session, within-subject protocol consisting of a 30-min rest period (R1), 30 min of videogame-based motor activity using a guitar controller (A1), and a second 30-min rest period (R2). Transcranial magnetic stimulation combined with surface electromyography assessed corticospinal excitability and activity of intracortical circuits in the first dorsal interosseous (FDI) and abductor digiti minimi (ADM). Gameplay performance significantly improved during the activity block, demonstrating short-term performance improvements took place. The 1mVSTIM MEP measure in FDI demonstrated a significant main effect across the three time points in the block, and pairwise comparisons showed that the 1mVSTIM MEP was significantly larger after R2 when compared with R1, and for R2 compared to A1. There were no significant changes in long interval intra-cortical inhibition, short intracortical inhibition or intracortical facilitation for the FDI. No changes were detected in the ADM. These findings suggest that adequate pre- and post-task rest may facilitate increased corticospinal excitability following novel motor task performance without altering measures of inhibition or facilitation.