Impulsivity is  a  core  feature  of  many  psychological  disorders,  including  attention- deficit/hyperactivity disorder (ADHD) and addiction. It is characterized by a failure to inhibit self-defeating behaviors, leading to actions such as gambling, drug-seeking, or premature actions resulting in negative outcomes. The premise of my approach is that understanding the neural mechanisms behind impulsivity as well as medications that reduce impulsivity will improve treatment outcome. Dopamine (DA) plays a critical role in regulating impulsive behavior, making it a key target for study. Despite its importance, real-time measurements of DA activity during behavior have been challenging. Our lab uses novel dopamine imaging in monkeys, being among the first to measure DA levels with sub-second resolution during waiting tasks, and the first to measure it in the cortex. This allows us to investigate the link between DA signaling and impulsivity in real-time. My preliminary findings indicate that impulsivity and dopamine increase with expected reward size. I hypothesize that DA signaling drives impulsivity and aim to investigate this by analyzing dopamine activity during impulsive behavior. Upon establishing the relation between dopamine and impulsivity, I aim to investigate the effects of Methylphenidate (MPH , Ritalin), a common ADHD treatment. MPH increases extracellular DA while reducing impulsivity, a paradoxically effect we hypothesize is due to the differential modulation of tonic and phasic DA responses. Our research aims to advance our understanding of dopamine’s role in impulsivity and offer crucial knowledge about the neural mechanisms underlying ADHD therapies, with the potential to improve mental health treatment outcomes.

supervisor: Prof. Mati Joshua