Expected results are (1) upregulation of activity in PMv using 0.1 Hz TMS will enhance motor memory formation induced by MT+AO more than sham TMS and downregulation of PMv using 0.9 Hz TMS and (2) dextromethorphan and scopolamine will decrease but rivastigmine will increase motor memory formation induced by MT+AO with placebo. This study may provide useful information on the mechanisms underlying the beneficial effects of action observation on neuroplasticity.