The Role of Dopaminergic and Noradrenergic Neurotransmission in Value- and Salience-based Decision-Making

Approach versus avoidance decisions are at the centre of adaptive behaviour and survival. These decisions are thought to be guided by the value of the choice options, which are a function of the magnitude of predicted rewards and punishments. Moreover, the allocation of attention to choice options is thought to be driven by salience, i.e. the overall importance of the predicted outcomes. While salience increases with the magnitude of both predicted rewards and predicted punishments, value increases with reward but decreases with punishment. In previous research, value and salience have often remained confounded during value-based decision making. Rodent research suggests that value is associated with dopamine and salience with norepinephrine. The present study aims at disentangling value from salience processing during decision-making tasks in healthy subjects by administering dopamine or noradrenaline reuptake inhibitors. This is done by using a single dose challenge in a randomized placebo-controlled between subject's design, administering either methylphenidate (35 mg), reboxetine (8 mg), or placebo to healthy young participants before they perform tasks tapping into various aspects of value and salience.