title: Density of available striatal dopamine receptors predicts trait impulsiveness during performance of an attention-demanding task.
abstract: The density (measured at binding potential) of available striatal D2/D3receptors has been shown to predict trait impulsiveness. This relationship is highly robust and well replicated. In each case, however, the availability of dopamine receptors was measured at rest. More broadly, the extent to which relationships between dopamine receptor availability and behavioral traits hold when participants perform a cognitive task is unclear. Furthermore, the performance of a cognitive task engages fundamentally different neural networks than are maximally engaged during the resting state. This complicates interpretation of previously observed correlations, which could be influenced by two distinct factors. The first is variation in available receptor density, which reflects a stable trait of the individual. The second is variation in context-specific dopamine release, which differentially displaces some dopamine radiotracers (such as raclopride) across individuals. Using an existing data set, we related trait impulsiveness, as measured using the Barratt Impulsiveness Scale (BIS-11), to the density (binding potential) of available striatal D2/D3receptors as measured using positron emission tomography (PET) with [11C]raclopride. Importantly, the PET scan was completed while participants performed an attention-demanding visual search task. We replicate robust correlations between this measure of receptor availability and trait impulsiveness previously demonstrated during the resting state, extending this relationship to periods of active task engagement. Our results support the idea that this relationship depends on striatal D2/D3receptor density and not on context-dependent dopamine release.NEW & NOTEWORTHYSeveral studies have demonstrated a relationship between the density of available striatal D2/D3receptors and trait impulsiveness. However, in each case, the availability of dopamine receptors was measured during the resting state. This complicates interpretation of previously observed correlations, which could be influenced by either stable variation in receptor density or context-dependent dopamine release. We present evidence uniquely consistent with the former interpretation, providing clarity to the nature of this brain-behavior relationship.
authors.affiliation: Department of Psychology, Texas A&M University, College Station, Texas; brian.anderson@tamu.edu.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Anderson
authors.affiliation: Section of High Resolution Brain PET, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Kuwabara
authors.affiliation: Section of High Resolution Brain PET, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.|Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland.|Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Dean F
authors.initials: DF
authors.lastname: Wong
authors.affiliation: Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland.|Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, Maryland; and.|F. M. Kirby Research Center, Kennedy Krieger Institute, Baltimore, Maryland.
authors.forename: Susan M
authors.initials: SM
authors.lastname: Courtney
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D007175:Impulsive Behavior; D008297:Male; D049268:Positron-Emission Tomography; D020891:Raclopride; D019275:Radiopharmaceuticals; D011954:Receptors, Dopamine / Q000378:metabolism*
chemical_list: D019275:Radiopharmaceuticals; D011954:Receptors, Dopamine; D020891:Raclopride
keywords: attention; dopamine; impulsiveness; positron emission tomography