RecruitingDevice studyLow-Intensity Focused Ultrasound Pulsation (LIFUP) for the Treatment of Generalized Anxiety Disorder (GAD)There are few treatment options available for patients once they have failed standard psychopharmacological therapy for generalized anxiety disorder. Existing brain stimulation methods such as rTMS fail to target deep brain structures associated with anxiety disorders; structures such as the amygdala. In this double-blind sham-controlled clinical trial, the investigators propose to establish baseline severity of anxiety in 48 patients, then deliver eight treatments over four sessions of focused ultrasound stimulation to the amygdala. Anxiety severity will be assessed using standard psychometric scales after each session, and at follow-ups.