title: On the molecular genetics of flexibility: the case of task-switching, inhibitory control and genetic variants.
abstract: The adjustment of behavior to changing goals and environmental constraints requires the flexible switching between different task sets. Cognitive flexibility is an endophenotype of executive functioning and is highly heritable, as indicated by twin studies. Individual differences in global flexibility as assessed by reaction-time measurement in a task-switching paradigm were recently related to a single nucleotide polymorphism in the vicinity of the dopamine d2 receptor gene DRD2. In the present study, we assessed whether the DRD2 gene is related to backward inhibition, a control mechanism that contributes to cognitive flexibility by reducing proactive interference by no longer relevant task sets. We found that carriers of the DRD2 A1+ variant who have a lower striatal dopamine d2 receptor density than A1- carriers show a larger backward inhibition effect. This is in line with previous results demonstrating increased behavioral flexibility in carriers of this genetic variant. The discussion relates the present finding to those of previous studies assessing the neurogenetic foundations of inhibitory control.
authors: University of Bonn, Germany. sebastian.markett@uni-bonn-diff.de
authors: Sebastian
authors: S
authors: Markett
authors: Christian
authors: C
authors: Montag
authors: Nora T
authors: NT
authors: Walter
authors: Thomas
authors: T
authors: Plieger
authors: Martin
authors: M
authors: Reuter
mesh_terms: D000293:Adolescent; D000328:Adult; D003071:Cognition / Q000502:physiology; D003342:Corpus Striatum / Q000502:physiology; D056344:Executive Function / Q000502:physiology*; D005260:Female; D005787:Gene Frequency; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D007206:Individuality; D007266:Inhibition, Psychological; D008297:Male; D017397:Prefrontal Cortex / Q000502:physiology*; D011930:Reaction Time / Q000235:genetics; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D012917:Social Adjustment
chemical_list: D017448:Receptors, Dopamine D2