The influence of dopamine autoreceptors on temperament and addiction risk.

As a major regulator of dopamine (DA), DA autoreceptors (DA) exert substantial influence over DA-mediated behaviors. This paper reviews the physiological and behavioral impact of DA. Individual differences in DA functioning influences temperamental traits such as novelty responsivity and impulsivity, both of which are associated with vulnerability to addictive behavior in animal models and a broad array of externalizing behaviors in humans. DA additionally impact the response to psychostimulants and other drugs of abuse. Human PET studies of D2-like receptors in the midbrain provide evidence for parallels to the animal literature. These data lead to the proposal that weak DA regulation is a risk factor for addiction and externalizing problems. The review highlights the potential to build translational models of the functional role of DA in behavior. It also draws attention to key limitations in the current literature that would need to be addressed to further advance a weak DA regulation model of addiction and externalizing risk.