**Appendix A**

Figure A1, Comparison of LTD-like group and LTP-like group prior (baseline) and following PAS (at 0, 10, and 20 min).

Figure A2, RS at 0, 10, and 20 min after PAS in LTD-like and LTP-like groups.

**Figure A1.** *Cont.*

**Figure A1.** (**a**) Normalized MEP amplitude (mean ± standard error) at dynamic level of RS and (**b**) MEP amplitude (mean <sup>±</sup> standard error) at stable level of RS, across the subjects from the LTP/LTD-like groups within the trials before (baseline) and at 0, 10, and 20 min after the induction of short-term plasticity with PAS. Subjects in the LTD-like group exhibited significantly higher pre-intervention MEP amplitudes (baseline) in dynamic RS (*p* = 0.005), and stable RS (*p* = 0.007). No significant difference was observed between the two clusters following PAS in either component. \*\*\* indicates significant differences for pairwise comparisons (*p* < 0.01).

**Figure A2.** RS at 0, 10, and 20 min after the induction of short-term plasticity with PAS (post-PAS). Effects of LTP/LTD-like plasticity were measured with respect to "baseline" pre-intervention neural activity. Irrespective of the dynamic state of RS, the brain shows a tendency towards a suppressed amplitude level of the second to the fourth MEPs within trials upon repetition of the stimulus. This static status was maintained within a narrow range in two groups after PAS.
