Corticospinal inhibition evoked by 1Hz repetitive transcranial magnetic stimulation depends on current direction and pulse waveform

Introduction: The potential of repetitive transcranial magnetic stimulation (rTMS) to modulate human corticospinal tract excitability has motivated experimental therapeutic trials in neurology and psychiatry. In many of these trials neither the stimulus configuration nor the current direction have been been taken into account. We hypothesized that the effects of rTMS on corticospinal excitability depend on the current direction used. Methods: 10 healthy controls (mean age 25.7 years) received 900 monophasic and biphasic repetitive transcranial magnetic stimuli over the optimal abductor digiti minimi of the prima…