title: Modulating effect of COMT genotype on the brain regions underlying proactive control process during inhibition.
abstract: BACKGROUND
  Genetic variability related to the catechol-O-methyltransferase (COMT) gene (Val(158)Met polymorphism) has received increasing attention as a possible modulator of cognitive control functions.
  
  
  METHODS
  In an event-related functional magnetic resonance imaging (fMRI) study, a modified version of the Stroop task was administered to three groups of 15 young adults according to their COMT Val(158)Met genotype [Val/Val (VV), Val/Met (VM) and Met/Met (MM)]. Based on the theory of dual mechanisms of control (Braver et al., 2007), the Stroop task has been built to induce proactive or reactive control processes according to the task context.
  
  
  RESULTS
  Behavioral results did not show any significant group differences for reaction times but Val allele carriers individuals are less accurate in the processing of incongruent items. fMRI results revealed that proactive control is specifically associated with increased activity in the anterior cingulate cortex (ACC) in carriers of the Met allele, while increased activity is observed in the middle frontal gyrus (MFG) in carriers of the Val allele.
  
  
  CONCLUSIONS
  These observations, in keeping with a higher cortical dopamine level in MM individuals, support the hypothesis of a COMT Val(158)Met genotype modulation of the brain regions underlying proactive control, especially in frontal areas as suggested by Braver et al.
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium; Department of Psychology: Cognition and Behavior, University of Liège, Liège, Belgium.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Jaspar
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium; Department of Psychology: Cognition and Behavior, University of Liège, Liège, Belgium.
authors.forename: Sarah
authors.initials: S
authors.lastname: Genon
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium; Department of Psychology: Cognition and Behavior, University of Liège, Liège, Belgium.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Muto
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium.
authors.forename: Christelle
authors.initials: C
authors.lastname: Meyer
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium; Department of Psychology: Cognition and Behavior, University of Liège, Liège, Belgium; Department of Genetics, University of Liège, Belgium.
authors.forename: Marine
authors.initials: M
authors.lastname: Manard
authors.affiliation: Department of Genetics, University of Liège, Belgium.
authors.forename: Vinciane
authors.initials: V
authors.lastname: Dideberg
authors.affiliation: Department of Genetics, University of Liège, Belgium.
authors.forename: Vincent
authors.initials: V
authors.lastname: Bours
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium.
authors.forename: Eric
authors.initials: E
authors.lastname: Salmon
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Maquet
authors.affiliation: Cyclotron Research Centre, University of Liège, Liège, Belgium; Department of Psychology: Cognition and Behavior, University of Liège, Liège, Belgium. Electronic address: f.collette@ulg.ac.be.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Collette
mesh_terms: D000293:Adolescent; D000328:Adult; D000483:Alleles; D001921:Brain / Q000201:enzymology*; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D004247:DNA / Q000235:genetics; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008715:Methionine; D010100:Oxygen / Q000097:blood; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D014633:Valine; D055815:Young Adult
chemical_list: D004247:DNA; D008715:Methionine; D002394:Catechol O-Methyltransferase; D014633:Valine; D010100:Oxygen
keywords: COMT gene; Cognitive control; Inhibition; Stroop task; fMRI