title: Indexing the graded allocation of visuospatial attention using anticipatory alpha oscillations.
abstract: Lateralization in the desynchronization of anticipatory occipitoparietal alpha (8-12 Hz) oscillations has been implicated in the allocation of selective visuospatial attention. Previous studies have demonstrated that small changes in the lateralization of alpha-band activity are predictive of behavioral performance but have not directly investigated how flexibly alpha lateralization is linked to top-down attentional goals. To address this question, we presented participants with cues providing varying degrees of spatial certainty about the location at which a target would appear. Time-frequency analysis of EEG data demonstrated that manipulating spatial certainty led to graded changes in the extent to which alpha oscillations were lateralized over the occipitoparietal cortex during the cue-target interval. We found that individual differences in alpha desynchronization contralateral to attention predicted reaction times, event-related potential measures of perceptual processing of targets, and beta-band (15-25 Hz) activity typically associated with response preparation. These results support the hypothesis that anticipatory alpha modulation is a plausible neural mechanism underlying the allocation of visuospatial attention and is under flexible top-down control.
authors.affiliation: Department of Experimental Psychology, University of Oxford, South Parks Road, Oxford OX1 3UD, UK. ian.gould@psy.ox.ac.uk
authors.forename: Ian C
authors.initials: IC
authors.lastname: Gould
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Rushworth
authors.forename: Anna C
authors.initials: AC
authors.lastname: Nobre
mesh_terms: D000328:Adult; D000513:Alpha Rhythm / Q000502:physiology*; D059031:Anticipation, Psychological / Q000502:physiology*; D001288:Attention / Q000502:physiology*; D001683:Biological Clocks / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology*; D006801:Humans; D008297:Male; D009778:Occipital Lobe / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology*; D013028:Space Perception / Q000502:physiology*