Transcranial Magnetic Stimulation for MCI

The investigators will treat participants with accelerated intermittent theta burst stimulation. iTBS will be delivered via a MagVenture MagPro TMS System with a Cool-B65 coil, targeting to direct the stimulation to the left dorsolateral prefrontal cortex (l-dlPFC). The investigators will use a standard resting motor threshold (rMT) determination to determine the TMS dose. Treatment will be delivered at 120% of the motor threshold. Total treatment time will be controlled; all participants will perceive receiving active treatment for 10 3-min sessions with 10-15 min inter-session intervals, resulting in a 3-hour treatment day. At pre-treatment, a focal electrical sham will be individually titrated to participant tolerability. Participants then receive an individualized level of sham stimulation throughout treatment, to bolster the blind. Participants will be told that they will be receiving different doses throughout the treatment day, again to maintain the integrity of the blind.

To achieve adequate blinding, participants will go through the same number of sessions per day irrespective of the active and/or sham dose-step combination to which they are assigned. Sham sessions will be assigned in random order over the 10 sessions. The sequence of active and/or sham sessions for each treatment day is assigned a random code that is entered into the TMS system by the coordinator to maintain the integrity of the blind.