title: Circles are different: the perception of Glass patterns modulates early event-related potentials.
abstract: Glass patterns are randomized dot arrays that generate the perception of a global structure. They consist of correlated dot pairs which are generated by geometric transformations. The present study employed behavioral and event-related brain potential (ERP) measures to characterize the underlying neuronal processing when such patterns are perceived. Stimuli were circular, parallel, and randomized Glass patterns presented in two isoluminant colors using a choice reaction paradigm. Sixteen subjects were instructed to differentiate between colors with a button-press response. The N170 component increased in amplitude for circular patterns, and this effect was most pronounced bilaterally over occipito-temporal areas. The results suggest that the global perception of form generated by Glass patterns occurs at a stage of visual processing past area V1.
authors.affiliation: Institute of General Psychology, University of Leipzig, Seeburgstr. 14-20, 04103 Leipzig, Germany. ohla@rz.uni-leipzig.de
authors.forename: Kathrin
authors.initials: K
authors.lastname: Ohla
authors.forename: Niko A
authors.initials: NA
authors.lastname: Busch
authors.forename: Markus A
authors.initials: MA
authors.lastname: Dahlem
authors.forename: Christoph S
authors.initials: CS
authors.lastname: Herrmann
mesh_terms: D000328:Adult; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008959:Models, Neurological; D009903:Optical Illusions; D011601:Psychophysics; D014796:Visual Perception / Q000502:physiology*