Measuring the Effects of Neurostimulation on Risky and Ambiguous Decision-Making Capacity in People With and Without Substance Use Disorder

Study Description: Risky decision-making is a core feature of substance use disorders and contributes to the compulsive behaviors seen in opioid use disorder (OUD). Risky decision-making can be separated into two distinct components: tolerance for known risks; and tolerance for unknown ambiguous risks. Tolerance for ambiguity in decision-making has been associated with increased risk of relapse in OUD, however conventional treatments for OUD rarely consider and target the dissociable components of decision-making that might underlie risky behaviors. In this study, we will utilize connectivity-based transcranial magnetic stimulation to selectively modulate ambiguity tolerance in decision-making in people with an OUD. Individualized cortical targets for stimulation will be derived from a baseline measurement of decision-making capacity. The ability for transcranial magnetic stimulation (TMS) to modulate ambiguity tolerance in decision-making will be assessed (relative to placebo stimulation), as well as clinical correlates, such as craving. Objectives: * Primary Objectives: * Determine neural correlates of risk and ambiguity tolerance in healthy controls and people with OUD. * Measure the impact of a type of TMS (theta burst stimulation) on ambiguity tolerance in healthy controls and people with OUD. * Secondary Objectives: * Determine the impact of TMS on resting-state brain activity. * Determine the impact TMS on outcomes that are relevant to substance use and relapse (e.g., craving). * Tertiary/Exploratory Objectives: * The effect of sex on the above metrics will be explored. Endpoints: The impact of transcranial magnetic stimulation on decision making will be assessed several ways. * Primary Endpoints: * Brain reactivity during decision-making task that separates tolerance for risk and tolerance for ambiguity. * Modulation of behavior and neural activity in areas of the brain associated with ambiguity tolerance by TMS. * Secondary Endpoints: * The influence of TMS on the brain s resting state function will be assessed. * The influence of TMS on substance use-related outcomes will be assessed. * Tertiary/Exploratory Endpoints: * Completion of baseline visit where neuromodulation is not administered.