1. MEP amplitude ratios for pre- and post-A-tDCS.
MEP amplitude ratios for pre- and post-A-tDCS. The y-axis represents the average MEP amplitude standardized to the pre-tDCS MEP amplitude and the x-axis represents successive TMS measurements taken before application of A-tDCS (Pre), immediately after A-tDCS (Post 1; P1) and repeated every 5 min up to 25 min post-A-tDCS (P2…P6). Black circles are the mean MEP amplitude for all subjects on D0 (Baseline Day). Gray diamonds are the mean MEP amplitude for all subjects on D1 (Training Day). Bar graphs depict average MEP amplitude for P1–P6 for Baseline Session (B) and for Training Session (T). Far left graph is MEP amplitudes for AA subjects after training Skill A. Second from left graph is MEP amplitudes for ABA subjects after training Skill A. Second from right graph is MEP amplitudes after training Skill B. Far right graph is the mean MEP amplitude for subjects in Group R (no learning). After training either Skill A or Skill B, subjects had a significant reduction of potentiation aftereffects following application of A-tDCS (occlusion) compared with following a period of rest. Subjects who trained on the randomized task showed similar amounts of LTP-like plasticity either at rest or following training demonstrating no occlusion when accumulation of learning does not occur. Data are means ± SEM. *p ≤ 0.05.
Gabriela Cantarero et al. J. Neurosci. 2013;33:
©2013 by Society for Neuroscience