A Pilot fMRI Study of TMS in Late-Life Severe Worry

Investigators will test a novel intervention through experimental therapeutic approach using fMRI-directed Intermittent Theta Burst Stimulation (iTBS), a high frequency TMS paradigm, for the treatment of severe, uncontrollable worry. While worry is a universal human experience, severe and excessive worry has been recently linked to increased risk of stroke and other cardiovascular diseases, increased risk of conversion to Alzheimer's disease as well as to higher risk of all-cause mortality in midlife and late-life. Severe, uncontrollable worry has been repeatedly associated with reduced quality of life and impaired functioning. Current treatment choices (antidepressant/anxiolytic medications and psychotherapeutic interventions) have been proven moderately efficacious in reducing anxiety/depression burden, but ineffective in reducing worry severity, a phenomenon that may contribute to the high relapse rates associated with mood and anxiety disorders. Our research indicated that worry severity is associated with hyperactivation in specific regions such as orbital frontal cortex, superior parietal gyrus, amygdala and parahippocampal gyrus. This pilot study will explore the efficacy of targeting one of these regions with iTBS. Based on investigators' previous results, the most accessible target is the right superior parietal gyrus (rSPG) - a region that remained significantly associated with severe worry after controlling for effects of comorbid depression or overall anxiety. As this region showed an increased in cerebrovascular flow in association with worry severity, investigators will use iTBS (5x/week for 2 weeks) to modulate cortical plasticity in this region and consequently, to reduce worry severity. TMS during wakefulness has been shown to alter subsequent sleep \[4\], Further, changes in sleep in response to TMS has been associated with how participants respond to the TMS as a treatment \[5\]. Thus, the study will measure sleep throughout the protocol to determine whether sleep changes as a function of TMS and whether sleep changes are associated with treatment response.