Figure 2.

Effect of different training interventions on TMS-evoked movement direction. A, Example of one subject. First-peak acceleration vectors of TMS-evoked thumb movements before (left) and after (right) each of the three interventions (PhysPract, ObsPract_opposite, and ObsPract_toward). For better comparability, all examples are aligned to the training direction indicated by the arrow. The TTZ is shown in gray. PhysPract and ObsPract_opposite, but not ObsPract_toward, led to substantial changes in the direction of TMS-evoked movements. B, Group data (n = 10) showing the P_TTZ before and after PhysPract, ObsPract_opposite, and ObsPract_toward. Before the training interventions, the percentage of TMS-evoked movements in TTZ was similar in PhysPract and ObsPract_opposite. PhysPract and ObsPract_opposite, but not ObsPract_toward, led to a significant increase in the percentage of TMS-evoked movements falling into TTZ. Data show means ± SEM. ^*p < 0.005. n.s., Not significant. C, Time course of changes of P_TTZ as a function of training intervention. To compare between conditions, ΔP_TTZ was computed as the baseline-normalized, intervention-dependent change in percentage of TMS-evoked thumb movements falling into the TTZ (see Materials and Methods). At the end of 30 min, the percentage change of TMS-evoked movements in TTZ was larger in PhysPract than in ObsPract_opposite or ObsPract_toward and with ObsPract_opposite than with ObsPract_toward. Rhombi, PhysPract; circles, ObsPract_opposite; triangles, ObsPract_toward. Filled symbols, Time points significantly different from baseline; two-tailed t tests; false discovery rate correction. ^*p < 0.05. D, Duration of changes of P_TTZ as a function of training intervention. Symbols as in C. Error bars represent SEM.