title: Dissociating early and late visual processing via the Ebbinghaus illusion.
abstract: Visual perception is not instantaneous; the perceptual representation of our environment builds up over time. This can strongly affect our responses to visual stimuli. Here, we study the temporal dynamics of visual processing by analyzing the time course of priming effects induced by the well-known Ebbinghaus illusion. In slower responses, Ebbinghaus primes produce effects in accordance with their perceptual appearance. However, in fast responses, these effects are reversed. We argue that this dissociation originates from the difference between early feedforward-mediated gist of the scene processing and later feedback-mediated more elaborate processing. Indeed, our findings are well explained by the differences between low-frequency representations mediated by the fast magnocellular pathway and high-frequency representations mediated by the slower parvocellular pathway. Our results demonstrate the potentially dramatic effect of response speed on the perception of visual illusions specifically and on our actions in response to objects in our visual environment generally.
authors.affiliation: Department of General Psychology,Justus-Liebig-University Giessen,D-35394 Giessen,Germany.
authors.forename: Filipp
authors.initials: F
authors.lastname: Schmidt
authors.affiliation: Department of Experimental Psychology,University of Kaiserslautern,D-67663 Kaiserslautern,Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Weber
authors.affiliation: Department of Clinical Psychology and Psychotherapy,Philipps-University Marburg,D-35032 Marburg,Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Haberkamp
mesh_terms: D005260:Female; D006801:Humans; D007088:Illusions / Q000502:physiology*; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Ebbinghaus illusion; Feedforward processing; Temporal dynamics; Time course; Visual illusions