Global statistical regularities modulate the speed of visual search in patients with focal attentional deficits

Lucilla Lanzoni, David Melcher, Gabriele Miceli, Jennifer E. Corbett*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

There is growing evidence that the statistical properties of ensembles of similar objects are processed in a qualitatively different manner than the characteristics of individual items. It has recently been proposed that these types of perceptual statistical representations are part of a strategy to complement focused attention in order to circumvent the visual system's limited capacity to represent more than a few individual objects in detail. Previous studies have demonstrated that patients with attentional deficits are nonetheless sensitive to these sorts of statistical representations. Here, we examined how such global representations may function to aid patients in overcoming focal attentional limitations by manipulating the statistical regularity of a visual scene while patients performed a search task. Three patients previously diagnosed with visual neglect searched for a target Gabor tilted to the left or right of vertical in displays of horizontal distractor Gabors. Although the local sizes of the distractors changed on every trial, the mean size remained stable for several trials. Patients made faster correct responses to targets in neglected regions of the visual field when global statistics remained constant over several trials, similar to age-matched controls. Given neglect patients' attentional deficits, these results suggest that stable perceptual representations of global statistics can establish a context to speed search without the need to represent individual elements in detail.

Original languageEnglish
Article number514
Pages (from-to)1-12
Number of pages12
JournalFrontiers in Psychology
Volume5
DOIs
Publication statusPublished - 12 Jun 2014
Externally publishedYes

Keywords

  • mean size representation
  • perceptual averaging
  • ensemble statistics
  • visual neglect
  • visual search
  • attention
  • REAL-WORLD SCENES
  • UNILATERAL NEGLECT
  • HEMISPATIAL NEGLECT
  • MEAN SIZE
  • REPRESENTATION
  • PERCEPTION
  • RECOGNITION
  • INFORMATION
  • INTEGRATION
  • DISPLAYS

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