title: The flexible mind is associated with the catechol-O-methyltransferase (COMT) Val158Met polymorphism: evidence for a role of dopamine in the control of task-switching.
abstract: Genetic variability related to the catechol-O-methyltransferase (COMT) gene (Val158Met polymorphism) has received increasing attention as a possible modulator of cognitive control functions. Recent evidence suggests that the Val158Met genotype may differentially affect cognitive stability and flexibility, in such a way that Val/Val homozygous individuals (who possess low prefrontal dopamine levels) may show more pronounced cognitive flexibility than Met/-carriers (who possess high prefrontal dopamine levels). To test this, healthy humans (n=87), genotyped for the Val158Met polymorphism at the COMT gene, performed a task-switching paradigm, which provides a relatively diagnostic index of cognitive flexibility. As predicted, Met/-carriers showed larger switching costs (i.e., less cognitive flexibility), F(1,85)=4.28, p<0.05, than Val/Val homozygous individuals. Our findings support the idea that low prefrontal dopamine levels promote cognitive flexibility.
authors.affiliation: Leiden University, Institute for Psychological Research & Leiden Institute for Brain and Cognition, Leiden, The Netherlands.
authors.forename: Lorenza S
authors.initials: LS
authors.lastname: Colzato
authors.forename: Florian
authors.initials: F
authors.lastname: Waszak
authors.forename: Sander
authors.initials: S
authors.lastname: Nieuwenhuis
authors.forename: Danielle
authors.initials: D
authors.lastname: Posthuma
authors.forename: Bernhard
authors.initials: B
authors.lastname: Hommel
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D003071:Cognition / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008715:Methionine / Q000235:genetics*; D009483:Neuropsychological Tests; D011110:Polymorphism, Genetic / Q000235:genetics*; D011930:Reaction Time / Q000235:genetics; D027544:Salvia / Q000378:metabolism; D014633:Valine / Q000235:genetics*; D055815:Young Adult
chemical_list: D008715:Methionine; D002394:Catechol O-Methyltransferase; D014633:Valine; D004298:Dopamine