title: When crowding of crowding leads to uncrowding.
abstract: In object recognition, features are thought to be processed in a hierarchical fashion from low-level analysis (edges and lines) to complex figural processing (shapes and objects). Here, we show that figural processing determines low-level processing. Vernier offset discrimination strongly deteriorated when we embedded a vernier in a square. This is a classic crowding effect. Surprisingly, crowding almost disappeared when additional squares were added. We propose that figural interactions between the squares precede low-level suppression of the vernier by the single square, contrary to hierarchical models of object recognition.
authors.affiliation: Laboratory of Psychophysics, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
authors.forename: Mauro
authors.initials: M
authors.lastname: Manassi
authors.forename: Bilge
authors.initials: B
authors.lastname: Sayim
authors.forename: Michael H
authors.initials: MH
authors.lastname: Herzog
mesh_terms: D005260:Female; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000502:physiology*; D012684:Sensory Thresholds / Q000502:physiology*; D014792:Visual Acuity / Q000502:physiology*; D014794:Visual Fields
keywords: contextual modulation; crowding; grouping; hierarchical processing; vernier acuity