I-wave periodicity transcranial magnetic stimulation (iTMS) on corticospinal excitability. A systematic review of the literature

•I-wave periodicity TMS (iTMS) is aimed to modulate corticospinal excitability.•Our systematic review revealed increased corticospinal excitability during iTMS.•Increased excitability post iTMS was seen for up to 25min (peaking at ∼10min).•iTMS studies reviewed demonstrated no reports of adverse events.•Studies were found to be of moderate quality, and a high risk of bias identified.