Mechanisms of Non-Invasive Neuromodulation Interventions: Influence on Human Neurochemistry and Functional Connectivity

Participants receive rTMS at a rate of 1 Hz, applied with a 70-mm figure-eight TMS coil connected to a stimulator, over the motor cortex hotspot contralateral to the dominant arm for 20 minutes at an intensity of 90% resting motor threshold (RMT) for a total of 600 TMS pulses. The total number of stimuli applied is well within the published safety guidelines for use of rTMS. rTMS is applied outside the scanner, whereas functional connectivity and neurochemistry are measured with MRI and MRS, respectively, at 7 Tesla. The MRI/MRS data are collected right before and immediately after the inhibitory rTMS intervention.

Participants receive rTMS at a rate of 5 Hz, applied with a 70-mm figure-eight TMS coil connected to a stimulator, over the motor cortex hotspot contralateral to the dominant arm for 20 minutes at an intensity of 90% RMT for a total of 600 TMS pulses. The total number of stimuli applied is well within the published safety guidelines for use of rTMS. rTMS is applied outside the scanner, whereas functional connectivity and neurochemistry are measured with MRI and MRS, respectively, at 7 Tesla. The MRI/MRS data are collected right before and immediately after the excitatory rTMS intervention.