Fig. 2.
Experimental protocol. Subjects came to the laboratory for 3 consecutive days (days 1–3). On each day, they performed the tokens task during 4 blocks of 50 trials (Block1–4; light gray rectangles). They also performed simple reaction time blocks at the beginning and at the end of each session (SRT1 and SRT2, respectively; dark gray rectangles). Day 1 served as a training session and did not involve any continuous theta burst stimulation (cTBS). cTBS train was applied for 40 s at the beginning of days 2 and 3 (red rectangles), either over the left (L) primary motor cortex (M1-Disruption session; black coil) or over the right (R) primary somatosensory cortex (Sham session; gray coil), in a randomized order. Motor evoked potentials (MEPs) were elicited at different time points (TMSEPOCHS) throughout the sessions (TMSBaseline and TMS1–7; yellow rectangles), either in the R first dorsal interosseous (FDI) muscle (M1-Disruption session) or in the L FDI (Sham session), by applying single-pulse TMS over the L or R M1, respectively. Note that in the Sham session, this implied targeting different sites for the cTBS intervention (R S1) and the MEP assessments (R M1; coil position not shown on the figure). M1, primary motor cortex; S1, primary somatosensory cortex; TMS, transcranial magnetic stimulation.