Human Brain Imaging Links Dopaminergic Systems to Impulsivity.
Molecular and functional imaging techniques have been used and combined with pharmacological probes to evaluate the role of dopamine in impulsivity. Overall, strong evidence links striatal dopaminergic function with impulsivity, measured by self-reports and laboratory tests of cognitive control and reward-based decision-making. The combination of molecular imaging using positron emission tomography (PET) with functional magnetic resonance imaging (fMRI) specifically implicates striatal D2-type dopamine receptors (i.e., D2 and D3) and corticostriatal connectivity in cognitive control. Low levels of striatal and midbrain D2-type receptor availability correlate with self-reported impulsivity, whereas striatal D2-type receptor availability shows positive correlation with motor response inhibition and cognitive flexibility. Impulsive choice on reward-based decision-making tasks also is related to deficits in striatal D2-type dopamine receptor availability, and there is evidence for an inverted U-shaped function in this relationship, reflecting an optimum of striatal dopaminergic activity. Findings from studies of clinical populations that present striatal dopamine D2-type receptor deficits as well as healthy control research participants identify D2-type receptors as therapeutic targets to improve cognitive control.
['London|Edythe D|ED|']
D003342:Corpus Striatum D004298:Dopamine D006801:Humans D007175:Impulsive Behavior D008279:Magnetic Resonance Imaging D059906:Neuroimaging D049268:Positron-Emission Tomography
Positron emission tomography Functional magnetic resonance imaging Response inhibition Cognitive flexibility D2 receptor Delay discounting