Repetitive Transcranial Magnetic Stimulation

Abstract

Transcranial magnetic stimulation (TMS) represents a valuable neurophysiological technique useful for both research and clinical practice purposes [1]. TMS acts by inducing electrical fields which cause electric currents to flow in targeted cortical areas. These currents interact with the electrical activity of the brain and can depolarize cortical interneurons and/or projection neurons depending on the characteristics of the stimulation. The induced excitation can spread throughout the nervous system by the brain’s normal mechanisms of propagation of neuronal signals. In this way, TMS can also induce functional changes in areas remote to the stimulated cortical area, including both functionally connected cortical regions (even in the contralateral hemisphere) and subcortical structures. Among major advantages of TMS are noninvasiveness, repeatability, high spatial and temporal resolution, the ability to modulate and measure cortical excitability and plasticity, and the proven therapeutic efficacy for the treatment of different neurological and psychiatric disorders [2]. Furthermore, safety and tolerability of TMS have been clearly established by a large number of studies [3, 4].