Stimulus intensity, coil characteristics and peripheral reafferent activation contribute to the suppressive effects of 1Hz rTMS on cortical excitability

Objective: Low-frequency (1Hz) repetitive transcranial magnetic stimulation (rTMS) to the primary motor cortex (M1) can suppress corticospinal excitability. Here we examined whether these inhibitory after effects depend on the stimulus intensity, the type of TMS coil and peripheral reafferent activation. Methods: In fifteen healthy volunteers, 900 biphasic pulses of 1Hz rTMS were given to the left M1 at an intensity of 90% or 115% of the individual resting motor threshold (subthreshold vs. suprathreshold intensity) using two commercially available 'figure-of-eight' shaped TMS coils (Magstim or Dantec coil) attac…