Dr Laura Grima, University of Oxford

Action and reward interactions in mesolimbic dopamine

There is broad consensus that the activity of midbrain dopaminergic neurons and downstream dopamine release in the nucleus accumbens core (NAcC) correlate with the difference between expected and received reward - a reward prediction error. Yet there is also evidence that  the activation of dopaminergic receptors on NAcC medium spiny neurons may play a causal role in motivating goal-directed action. However, the exact relationship between dopamine, prediction errors and action initiation remains controversial.  To investigate this interaction, I have used fast-scan cyclic voltammetry and targeted pharmacological manipulations in rodents in conjunction with a novel behavioural task that varies both action requirements and available reward in a factorial design. I will discuss findings that demonstrate an influence of action initiation on canonical prediction error signalling, as well as the importance of dopamine D1-receptor activation in the NAcC for cue-driven action.