rTMS, Stress and Opioid Use Disorder

Description

The Competing Neurobehavioral Decisions Systems (CNDS) model of addiction suggests that people with SUDs have altered function and connectivity in fronto-cortical executive control regions (e.g. dorsolateral prefrontal cortex [dlPFC]) and fronto-cortical limbic control regions (e.g. medial prefrontal cortex [mPFC]). Namely, elevated activity in limbic circuitry results in hypersensitivity to drug cues and stress, and decreased executive control impairs the ability to resist drug urges. The CNDS theoretical framework can guide selection and testing of rTMS targets that could improve understanding of the mechanisms of SUDs and stress-induced drug use. Results from previous research suggest that therapeutic effects of rTMS for SUD could occur via excitation of dlPFC or inhibition of mPFC.

The investigators will administer excitatory (10Hz) dlPFC rTMS and inhibitory (1Hz) mPFC rTMS (through an electromagnetic coil placed against the scalp) coupled with tasks of executive function and emotional arousal during stress and neutral conditions (guided imagery task using personalized scripts) in adults with OUD early in methadone treatment. The investigators will examine and compare how strengthening dlPFC activity or reducing mPFC activity may reverse stress-induced executive and emotional dysfunction, respectively, and improve treatment outcomes in persons with OUD seeking to abstain from opioid use.

A mixed design study will be used to examine the effects of active rTMS vs. sham (within subject) over one of two locations: 10 Hz dlPFC rTMS (group 1) or 1 Hz mPFC rTMS (group 2) in subjects receiving methadone treatment for OUD. The general rTMS treatment protocol will be the same for both groups and will consist of 2 stimulation sessions per day, separated by ~30min, for 5 days (10 total stimulation sessions per treatment protocol). The sham protocol will be the same except the sham rTMS coil will be used. Participants will be randomly assigned to groups and complete the 2 conditions (active vs. sham rTMS) in random order. Immediately prior to and after each 5-day rTMS treatment protocol, participants will attend an assessment visit when they will complete multiple tasks during both stress (guided imagery stressor) and neutral conditions. These tasks are designed to measure executive function, emotional arousal, and drug-seeking behavior.