title: Dopamine transporter genotype is associated with a lateralized resistance to distraction during attention selection.
abstract: Although lateral asymmetries in orienting behavior are evident across species and have been linked to interhemispheric asymmetries in dopamine signaling, the relative contribution of attentional versus motoric processes remains unclear. Here we took a cognitive genetic approach to adjudicate between roles for dopamine in attentional versus response selection. A sample of nonclinical adult humans (N = 518) performed three cognitive tasks (spatial attentional competition, spatial cueing, and flanker tasks) that varied in the degree to which they required participants to resolve attentional or response competition. All participants were genotyped for two putatively functional tandem repeat polymorphisms of the dopamine transporter gene (DAT1; SLC6A3), which are argued to influence the level of available synaptic dopamine and confer risk to disorders of inattention. DAT1 genotype modulated the task-specific effects of the various task-irrelevant stimuli across both the spatial competition and spatial cueing but not flanker tasks. Specifically, compared with individuals carrying one or two copies of the 10-repeat DAT1 allele, individuals without this allele demonstrated an immunity to distraction, such that response times were unaffected by increases in the number of distractor stimuli, particularly when these were presented predominantly in the left hemifield. All three genotype groups exhibited uniform costs of resolving leftward response selection in a standard flanker task. None of these significant effects could be explained by speed-accuracy trade-offs, suggesting that participants without the 10-repeat allele of the DAT1 tandem repeat polymorphism possess an enhanced attentional ability to suppress task-irrelevant stimuli in the left hemifield.
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia.
authors.forename: Daniel P
authors.identifier: http://orcid.org/0000-0001-8240-1876
authors.initials: DP
authors.lastname: Newman
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia.
authors.forename: Tarrant D R
authors.initials: TD
authors.lastname: Cummins
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia.
authors.forename: Janette H S
authors.initials: JH
authors.lastname: Tong
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia.
authors.forename: Beth P
authors.initials: BP
authors.lastname: Johnson
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia.
authors.forename: Hayley
authors.initials: H
authors.lastname: Pickering
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia.
authors.forename: Peter
authors.identifier: http://orcid.org/0000-0002-6074-5130
authors.initials: P
authors.lastname: Fanning
authors.affiliation: The University of Queensland, Queensland Brain Institute and School of Psychology, Brisbane, Queensland 4072, Australia, and.
authors.forename: Joseph
authors.initials: J
authors.lastname: Wagner
authors.affiliation: The University of Queensland, Queensland Brain Institute and School of Psychology, Brisbane, Queensland 4072, Australia, and.
authors.forename: Jack T T
authors.initials: JT
authors.lastname: Goodrich
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia.
authors.forename: Ziarih
authors.initials: Z
authors.lastname: Hawi
authors.affiliation: Cardiff University, School of Psychology, Cardiff CF10 3AT, United Kingdom.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Chambers
authors.affiliation: Monash University, School of Psychological Sciences, Clayton, Victoria 3800, Australia, The University of Queensland, Queensland Brain Institute and School of Psychology, Brisbane, Queensland 4072, Australia, and mark.bellgrove@monash.edu.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Bellgrove
mesh_terms: D001288:Attention / Q000502:physiology*; D003071:Cognition / Q000502:physiology; D003463:Cues; D050483:Dopamine Plasma Membrane Transport Proteins / Q000235:genetics*; D005260:Female; D007839:Functional Laterality / Q000235:genetics / Q000502:physiology; D005838:Genotype; D006801:Humans; D008297:Male; D009949:Orientation / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology; D013028:Space Perception / Q000502:physiology; D055815:Young Adult
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; C493214:SLC6A3 protein, human
keywords: DAT1; dopamine; genetics; individual differences; selective attention; spatial attention