title: Dopamine response to psychosocial stress in humans and its relationship to individual differences in personality traits.
abstract: BACKGROUND
  Previous studies have reported inter-individual variability in the dopamine (DA) response to stress. This variability might be related to individual differences in the vulnerability to experience the negative effect of stress.
  
  
  OBJECTIVE
  To investigate whether personality traits as measured by the revised NEO personality inventory explain variability in DA response to a psychosocial stress task.
  
  
  METHODS
  Eleven healthy adults, mean age of 26 ± 3.87 underwent two positron emission tomography (PET) scans using the dopamine D(2/3) agonist, [11C]-(+)-PHNO under a control and stress condition. The simplified reference tissue model (SRTM) was used to obtain [11C]-(+)-PHNO binding potential (BP(ND)). Stress-induced DA response was indexed as a percent change in [11C]-(+)-PHNO BP(ND) between control and stress conditions. The regions of interest were defined into D2-rich regions, which included the Associative and Sensorimotor Striatum (AST and SMST); D(2/3) mixed regions, which included the limbic striatum (LST) and globus pallidus (GP); and D3-rich region, which included the Substantia Nigra (SN).
  
  
  RESULTS
  Several personality traits within the Neuroticism and Openness to Experience domain were significantly correlated with blunted DA response to stress. Specifically, the Angry-Hostility, Vulnerability, and Depression trait were associated with blunted DA stress response in the AST (r = -0.645, p = 0.032), LST (r = -0.677, p = 0.022) and GP (r = -0.736, p = 0.010), respectively. The Openness to Values was correlated with a decreased DA release in the SN (r = -0.706, p = 0.015).
  
  
  CONCLUSIONS
  Variability in DA stress response might be related to individual differences in personality.
authors.affiliation: Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Canada.
authors.forename: Ivonne
authors.initials: I
authors.lastname: Suridjan
authors.forename: Isabelle
authors.initials: I
authors.lastname: Boileau
authors.forename: Michael
authors.initials: M
authors.lastname: Bagby
authors.forename: Pablo M
authors.initials: PM
authors.lastname: Rusjan
authors.forename: Alan A
authors.initials: AA
authors.lastname: Wilson
authors.forename: Sylvain
authors.initials: S
authors.lastname: Houle
authors.forename: Romina
authors.initials: R
authors.lastname: Mizrahi
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002247:Carbon Isotopes / Q000493:pharmacokinetics; D003342:Corpus Striatum / Q000000981:diagnostic imaging; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D006801:Humans; D007206:Individuality; D008279:Magnetic Resonance Imaging; D008297:Male; D010078:Oxazines / Q000493:pharmacokinetics; D010551:Personality; D010555:Personality Inventory; D049268:Positron-Emission Tomography; D011485:Protein Binding / Q000187:drug effects; D011581:Psychological Tests; D011954:Receptors, Dopamine / Q000378:metabolism; D013315:Stress, Psychological / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D055815:Young Adult
chemical_list: D002247:Carbon Isotopes; D010078:Oxazines; D011954:Receptors, Dopamine; D004298:Dopamine