Dopamine, reward, and frontostriatal circuitry in impulse control disorders in Parkinson's disease: insights from functional imaging.

Dopamine agonists have been implicated in the development of impulse control disorders (ICDs). This may be due to the ability of agonists to tonically stimulate dopamine receptors. Recent neuroimaging data provided evidence that dopamine agonists induce significant changes in those frontostriatal circuits that process reward and mediate our ability to control impulses. Tonic stimulation of dopamine receptors via agonists may impair reward processing and inhibitory control mechanisms in ways that promote pathological repetition of behaviors. We will provide an overview of the current understanding of the neurobiology underlying ICDs in Parkinson's disease (PD).