title: Robust sampling of decision information during perceptual choice.
abstract: Humans move their eyes to gather information about the visual world. However, saccadic sampling has largely been explored in paradigms that involve searching for a lone target in a cluttered array or natural scene. Here, we investigated the policy that humans use to overtly sample information in a perceptual decision task that required information from across multiple spatial locations to be combined. Participants viewed a spatial array of numbers and judged whether the average was greater or smaller than a reference value. Participants preferentially sampled items that were less diagnostic of the correct answer ("inlying" elements; that is, elements closer to the reference value). This preference to sample inlying items was linked to decisions, enhancing the tendency to give more weight to inlying elements in the final choice ("robust averaging"). These findings contrast with a large body of evidence indicating that gaze is directed preferentially to deviant information during natural scene viewing and visual search, and suggest that humans may sample information "robustly" with their eyes during perceptual decision-making.
authors.affiliation: Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom hildward.vandormael@sjc.ox.ac.uk.
authors.forename: Hildward
authors.initials: H
authors.lastname: Vandormael
authors.affiliation: Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom.
authors.forename: Santiago
authors.initials: S
authors.lastname: Herce Castañón
authors.affiliation: Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom.
authors.forename: Jan
authors.initials: J
authors.lastname: Balaguer
authors.affiliation: Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom.
authors.forename: Vickie
authors.initials: V
authors.lastname: Li
authors.affiliation: Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom.
authors.forename: Christopher
authors.initials: C
authors.lastname: Summerfield
mesh_terms: D002755:Choice Behavior / Q000502:physiology; D003657:Decision Making / Q000502:physiology*; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D006801:Humans; D007858:Learning; D008297:Male; D014796:Visual Perception / Q000502:physiology*
keywords: categorization; decision-making; eye movements; information sampling; numerical averaging