Currently rTMS for treating depression is delivered without knowing whether the TMS pulses are synchronized with the patient's brain rhythms. We will study healthy and depressed adults with TMS inside of the MRI scanner or outside of the MRI scanner using optics, and test whether it matters precisely timing the TMS pulses with EEG.

Transcranial focused ultrasound (tFUS) is a new noninvasive way to stimulate the brain in an awake and alert person. We do not yet have an easily observable way to know whether we are in the right brain location with the correct dose for that person. We wonder if we can produce a transient change in someone's visual field, called a scotoma, and whether we can use that to determine the minimum tFUS dose for that person.