Pharmaco-Neuroimaging Studies of Approach/Avoidance Behaviors and Post-Mortem Studies: Pharmacological Manipulation

Participants in the experimental arms will receive 40 mg of the nociceptin receptor antagonist. Peak concentrations are achieved 2-4 hours post-administration.

As part of the approach/avoidance task, electrotactile stimulation will be used. The aversive stimulus is delivered in the form of a mild half-second stimulation to the ankle, calibrated to a subjective threshold that is uncomfortable but not painful. This stimulation is delivered by Digitimer DS8R Constant Current Stimulator (Digitimer North America, LLC. Ft. Lauderdale, FL). Its previous model, DS71, has been safely implemented in studies within Massachusetts General Hospital (Milad et al., 2013).