20 Hz rTMS
DeviceRepetitive transcranial magnetic stimulation (rTMS) is a non-invasive neuromodulation technique that received FDA clearance for use in treatment resistant major depressive disorder in 2008. rTMS utilizes the application of a repetitively pulsed magnetic field over the scalp to induce an electric field within a discrete area of the cerebral cortex. This electric field results in altered ion flow across the neuronal cellular membrane and ultimately changes in neuronal polarization. rTMS modulates cortical activation depending on the stimulation parameters used. Physiological studies have provided evidence that suggests that high-frequency (HF) rTMS produces an increase in local cortical excitability. Studies have also demonstrated that rTMS may increase or decrease functional connectivity between separate but related cortical structures, utilizing high and low frequency stimulation, respectively.