Differential effects of 5-HTTLPR and DRD2/ANKK1 polymorphisms on electrocortical measures of error and feedback processing in children
Accepted 11 October 2008.
Abstract
Objective
Applying a probabilistic learning task we examined the influence of functional polymorphisms of the serotonin transporter gene (5-HTTLPR) and the D2 dopamine receptor gene (DRD2/ANKK1) on error and feedback processing by measuring electrocortical event-related potentials (ERPs) in 10- to 12-year-old children.
Methods
Three pairwise group comparisons were conducted on four distinguishable ERP components, two of which were response-related, the other two feedback-related.
Results
Our ERP data revealed that children carrying the short (S) variant of the 5-HTTLPR gene process their errors more intensively while exhibiting less habituation to negative feedback with task progression compared to children who are homozygous for the 5-HTTLPR long (L) variant. Children possessing the Taq1 A variant of the DRD2 gene showed greater sensitivity to negative feedback and, as opposed to Taq1 A non-carriers, a diminishing sensitivity to positive feedback with task progression. Regarding error processing, children possessing both the S variant of the 5-HTTLPR and the Taq1 A allele of the DRD2 gene showed a picture quite similar to that of the 5-HTTLPR S carriers and regarding feedback processing quite similar to that of the DRD2 Taq1 A carriers.
Conclusions
Our findings support the hypotheses that the 5-HTTLPR S allele may predispose to (performance) anxiety, while DRD2 Taq1 A allele may predispose to the reward deficiency syndrome.
Significance
The results may further enhance our understanding of known associations between these polymorphisms and psychopathology.
aDepartment of Child and Adolescent Psychiatry, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
bDepartment of Experimental and Work Psychology, University of Groningen, Groningen, The Netherlands
cDepartment of Pathology and Laboratory Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
ABSTRACT