Are there benefits of Visual Crowding?

Abstract

Objects in peripheral vision are less identifiable when flanked by nearby distractors. This loss in performance, known as visual crowding, has traditionally been viewed to result from a bottleneck in visual processing (e.g. Levi, Vision Research, 2008). Here we will present the alternate view that crowding could serve to suppress the representation of repetitive items in peripheral vision so that attentional resources can be directed to non-repetitive, interesting and novel items, potentially as the targets of upcoming saccades. Traditionally, crowding experiments have maximized the degradation of target-object identification by presenting targets and distractors with similar characteristics (Kooi et al., Spatial Vision, 1994) or that group together strongly (Manassi et al., Journal of Vision, 2012). These conditions yield robust target-flanker interactions extending over long distances (Bouma, Nature 1970; Tripathy et al., Journal of Vision, 2014). However, rather than representing a limitation of peripheral visual processing, the strong suppression of repetitive or similar items might be desirable, serving to enhance the individuation and processing of eccentrically viewed novel objects. In agreement with this interpretation, crowding is known to be minimal in foveal vision, is strongest between repetitive or similar objects in peripheral vision and between items that readily group together, and is reduced by target-flanker differences in contrast polarity, color, depth, shape, or complexity. Crowding also is weakened when transients increase the conspicuity of the target relative to the flankers and when the target represents the end-point of a planned saccade. This presentation will evaluate previous studies of crowding to ascertain whether the results can be understood better in terms of an implicit deficit in the processing of nearby visual targets or in terms of a beneficial suppression of repetitive peripheral stimuli so that processing resources can be devoted more fully to unfixated objects that are novel and potentially interesting. Meeting abstract presented at VSS 2017