ABSTRACT
UNLABELLED: According to twin studies heritability of cognitive skills is substantial, however, little is known about the gene variants responsible for coding individual variability. Results of candidate gene studies implicate an important role of the dopaminergic system in coding individual differences in reaction time performance, and the possible role of the function of the serotonergic system has also emerged. GOALS: The aim of our study was to carry out association analyses between performance on the Stroop-task and selected gene polymorphisms of the dopaminergic and serotonergic system. RESULTS: In this study we examined 179 young adult's Stroop-performance measuring the attentional inhibition. The number of mistakes showed remarkable individual variability which can be related to the polymorphisms of the dopamine D4 receptor gene according to several previous studies. The short and long variations of the variable number tandem repeat polymorphism in the promoter region of the serotonin transporter gene was also studied based on the hypothesis of dopamine-serotonin balance. CONCLUSION: Our results demonstrate that the performance in the Stroop task is related to the genetic variants of the dopaminergic, as well as the serotonergic system.
