title: Preparatory Encoding of the Fine Scale of Human Spatial Attention.
abstract: Our attentional focus is constantly shifting: In one moment, our attention may be intently concentrated on a specific spot, whereas in another moment we might spread our attention more broadly. Although much is known about the mechanisms by which we shift our visual attention from place to place, relatively little is known about how we shift the aperture of attention from more narrowly to more broadly focused. Here we introduce a novel attentional distribution task to examine the neural mechanisms underlying this process. In this task, participants are presented with an informative cue that indicates the location of an upcoming target. This cue can be perfectly predictive of the exact target location, or it can indicate-with varying degrees of certainty-approximately where the target might appear. This cue is followed by a preparatory period in which there is nothing on the screen except a central fixation cross. Using scalp EEG, we examined neural activity during this preparatory period. We find that, with decreasing certainty regarding the precise location of the impending target, participant RTs increased whereas target identification accuracy decreased. Additionally, the multivariate pattern of preparatory period visual cortical alpha (8-12 Hz) activity encoded attentional distribution. This alpha encoding was predictive of behavioral accuracy and RT nearly 1 sec later. These results offer insight into the neural mechanisms underlying how we use information to guide our attentional distribution and how that influences behavior.
authors.affiliation: 1 University of California, San Francisco.|2 University of California, San Diego.
authors.forename: Bradley
authors.initials: B
authors.lastname: Voytek
authors.affiliation: 1 University of California, San Francisco.|3 University of Wisconsin-Madison.
authors.forename: Jason
authors.initials: J
authors.lastname: Samaha
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Camarin E
authors.initials: CE
authors.lastname: Rolle
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Zachery
authors.initials: Z
authors.lastname: Greenberg
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Navdeep
authors.initials: N
authors.lastname: Gill
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Shai
authors.initials: S
authors.lastname: Porat
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Tahim
authors.initials: T
authors.lastname: Kader
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Sabahat
authors.initials: S
authors.lastname: Rahman
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Rick
authors.initials: R
authors.lastname: Malzyner
authors.affiliation: 1 University of California, San Francisco.
authors.forename: Adam
authors.initials: A
authors.lastname: Gazzaley
mesh_terms: D000328:Adult; D059031:Anticipation, Psychological / Q000502:physiology*; D001288:Attention / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D006801:Humans; D009483:Neuropsychological Tests; D011930:Reaction Time; D013028:Space Perception / Q000502:physiology*; D055815:Young Adult