Fig. 2

Meta-analyses indicating the effects of low frequency repetitive transcranial magnetic stimulation (LF-rTMS) to the unaffected M1 in modulating bilateral cortical excitability. The meta-analysis showed that LF-rTMS was significantly effective to decrease (a) and increase (b) rMT of the affected and unaffected M1 after multiple sessions of stimulation, respectively. Although LF-rTMS also tended to increase the aMT of the unaffected M1, the pooled Hedges’ g value was not significant (c). A single session of LF-rTMS significantly increased the MEP amplitude of the affected M1 by 22.14% (d); similar results were also found after multiple sessions of stimulation (f). Conversely, the MEP amplitude of the unaffected M1 significantly decreased by 21.29% immediately after a single session of LF-rTMS (e); similarly, the MEP amplitude of the unaffected M1 significantly decreased after multiple sessions of LF-rTMS (g). rMT resting motor threshold; aMT active motor threshold, MEP motor-evoked potentials