title: Nasotemporal ERP differences: evidence for increased inhibition of temporal distractors.
abstract: Previous research has demonstrated behavioral advantages for stimuli in the temporal relative to the nasal visual hemifield. To investigate whether this nasotemporal asymmetry reflects a genuinely attentional bias, we recorded event-related potentials in a task where participants identified a color-defined target digit in one visual hemifield that was accompanied by an irrelevant distractor in the opposite hemifield (experiment 1). To dissociate the processing of stimuli in nasal and temporal visual hemifields, an eye-patching procedure was used. Targets triggered N2pc components that marked their attentional selection. Unexpectedly, these N2pc components were larger and emerged earlier for nasal relative to temporal targets. Experiment 2 provided evidence that this nasotemporal asymmetry for the N2pc is linked to an increased attentional inhibition of temporal distractors. Relative to nasal distractors, temporal distractors elicited an increased inhibition-related contralateral positivity, resulting in more pronounced differences between contralateral and ipsilateral event-related potentials on trials with temporal distractors and nasal targets. These results provide novel evidence for a genuinely attentional contribution to nasotemporal asymmetries and suggest that such asymmetries are associated with top-down controlled distractor inhibition.
authors.affiliation: Department of Basic Psychological Research and Research Methods, University of Vienna, Vienna, Austria; and christoph.huber-huber@univie.ac.at.
authors.forename: Christoph
authors.initials: C
authors.lastname: Huber-Huber
authors.affiliation: School of Psychology, Birkbeck College, University of London, London, United Kingdom.
authors.forename: Anna
authors.initials: A
authors.lastname: Grubert
authors.affiliation: Department of Basic Psychological Research and Research Methods, University of Vienna, Vienna, Austria; and.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Ansorge
authors.affiliation: School of Psychology, Birkbeck College, University of London, London, United Kingdom.
authors.forename: Martin
authors.initials: M
authors.lastname: Eimer
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D003463:Cues; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology*; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D009666:Nose; D013028:Space Perception / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*
keywords: N2pc; attention; event-related potentials; inhibition; nasotemporal asymmetry; visual hemifield