title: Variation in key genes of serotonin and norepinephrine function predicts gamma-band activity during goal-directed attention.
abstract: Recent evidence shows that genetic variations in key regulators of serotonergic (5-HT) signaling explain variance in executive tasks, which suggests modulatory actions of 5-HT on goal-directed selective attention as one possible underlying mechanism. To investigate this link, 130 volunteers were genotyped for the 5-HT transporter gene-linked polymorphic region (5-HTTLPR) and for a variation (TPH2-703 G/T) of the TPH2 gene coding for the rate-limiting enzyme of 5-HT synthesis in the brain. Additionally, a functional polymorphism of the norepinephrine transporter gene (NET -3081 A/T) was considered, which was recently found to predict attention and working memory processes in interaction with serotonergic genes. The flanker-based Attention Network Test was used to assess goal-directed attention and the efficiency of attentional networks. Event-related gamma-band activity served to indicate selective attention at the intermediate phenotype level. The main findings were that 5-HTTLPR s allele and TPH2 G-allele homozygotes showed increased induced gamma-band activity during target processing when combined with the NET A/A genotype compared with other genotype combinations, and that gamma activity mediates the genotype-specific effects on task performance. The results further support a modulatory role of 5-HT and NE function in the top-down attentional selection of motivationally relevant over competing or irrelevant sensory input.
authors.affiliation: Department of Psychology, Technische Universitaet Dresden, 01062 Dresden, Germany.
authors.forename: Sören
authors.initials: S
authors.lastname: Enge
authors.forename: Monika
authors.initials: M
authors.lastname: Fleischhauer
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Lesch
authors.forename: Andreas
authors.initials: A
authors.lastname: Reif
authors.forename: Alexander
authors.initials: A
authors.lastname: Strobel
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000502:physiology*; D058256:Brain Waves / Q000235:genetics*; D004569:Electroencephalography; D005260:Female; D014644:Genetic Variation / Q000235:genetics*; D005838:Genotype; D006040:Goals; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D009483:Neuropsychological Tests; D009638:Norepinephrine / Q000235:genetics*; D011237:Predictive Value of Tests; D012701:Serotonin / Q000235:genetics*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics; D014365:Tryptophan Hydroxylase / Q000235:genetics; D055815:Young Adult
chemical_list: D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin; C494784:TPH2 protein, human; D014365:Tryptophan Hydroxylase; D009638:Norepinephrine