title: Perception of ensemble statistics requires attention.
abstract: To overcome inherent limitations in perceptual bandwidth, many aspects of the visual world are represented as summary statistics (e.g., average size, orientation, or density of objects). Here, we investigated the relationship between summary (ensemble) statistics and visual attention. Recently, it was claimed that one ensemble statistic in particular, color diversity, can be perceived without focal attention. However, a broader debate exists over the attentional requirements of conscious perception, and it is possible that some form of attention is necessary for ensemble perception. To test this idea, we employed a modified inattentional blindness paradigm and found that multiple types of summary statistics (color and size) often go unnoticed without attention. In addition, we found attentional costs in dual-task situations, further implicating a role for attention in statistical perception. Overall, we conclude that while visual ensembles may be processed efficiently, some amount of attention is necessary for conscious perception of ensemble statistics.
authors.affiliation: Department of Psychology, Reed College, United States.
authors.forename: Molly
authors.initials: M
authors.lastname: Jackson-Nielsen
authors.affiliation: Department of Brain and Cognitive Sciences, McGovern Institute for Brain Research, Massachusetts Institute of Technology, United States.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Cohen
authors.affiliation: Department of Psychology, Reed College, United States. Electronic address: mpitts@reed.edu.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Pitts
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D003118:Color Perception / Q000502:physiology*; D003243:Consciousness / Q000502:physiology*; D006801:Humans; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012858:Size Perception / Q000502:physiology*; D055815:Young Adult
keywords: Color diversity; Conscious perception; Dual-task; Inattentional blindness; Summary statistics; Visual ensembles