The role of dopamine in cognition: evidence from functional imaging studies.

Functional imaging provides a sensitive means of studying the dopaminergic system in the brain. Both pre-synaptic and post-synaptic aspects of this system can be explored, and recent technical advances even allow the estimation of the synaptic level of dopamine in the striatum. However, only a few studies have used functional imaging to identify the role of dopamine in cognition. This paper reviews recent evidence provided by studies in healthy individuals and patients with Parkinson's disease or schizophrenia supporting the role of dopamine in normal and pathological cognitive processes.