title: The timing of feedback to early visual cortex in the perception of long-range apparent motion.
abstract: When 2 visual stimuli are presented one after another in different locations, they are often perceived as one, but moving object. Feedback from area human motion complex hMT/V5+ to V1 has been hypothesized to play an important role in this illusory perception of motion. We measured event-related responses to illusory motion stimuli of varying apparent motion (AM) content and retinal location using Electroencephalography. Detectable cortical stimulus processing started around 60-ms poststimulus in area V1. This component was insensitive to AM content and sequential stimulus presentation. Sensitivity to AM content was observed starting around 90 ms post the second stimulus of a sequence and most likely originated in area hMT/V5+. This AM sensitive response was insensitive to retinal stimulus position. The stimulus sequence related response started to be sensitive to retinal stimulus position at a longer latency of 110 ms. We interpret our findings as evidence for feedback from area hMT/V5+ or a related motion processing area to early visual cortices (V1, V2, V3).
authors.affiliation: MEG Unit, Brain Imaging Center, J.W. Goethe Universität, Heinrich Hoffmann Strasse 10, Frankfurt am Main, Germany. wibral@bic.uni-frankfurt.de
authors.forename: Michael
authors.initials: M
authors.lastname: Wibral
authors.forename: Christoph
authors.initials: C
authors.lastname: Bledowski
authors.forename: Axel
authors.initials: A
authors.lastname: Kohler
authors.forename: Wolf
authors.initials: W
authors.lastname: Singer
authors.forename: Lars
authors.initials: L
authors.lastname: Muckli
mesh_terms: D000328:Adult; D001931:Brain Mapping; D004569:Electroencephalography / Q000379:methods; D005246:Feedback / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D009038:Motion; D009039:Motion Perception / Q000502:physiology*; D009903:Optical Illusions / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods*; D011930:Reaction Time / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*