title: Unconscious priming requires early visual cortex at specific temporal phases of processing.
abstract: Although examples of unconscious shape priming have been well documented, whether such priming requires early visual cortex (V1/V2) has not been established. In the current study, we used TMS of V1/V2 at varying temporal intervals to suppress the visibility of preceding shape primes while the interval between primes and targets was kept constant. Our results show that, although conscious perception requires V1/V2, unconscious priming can occur without V1/V2 at an intermediate temporal interval but not at early (5-25 msec) or later (65-125 msec) stages of processing. Because the later time window of unconscious priming suppression has been proposed to interfere with feedback processing, our results further suggest that feedback processing is also essential for unconscious priming and may not be a sufficient condition for conscious vision.
authors.affiliation: Department of Psychology, NAC 7/120, City College, City University of New York, 160 Convent Avenue, New York, NY 10031, USA. mpersuh@gmail.com
authors.forename: Marjan
authors.initials: M
authors.lastname: Persuh
authors.forename: Tony
authors.initials: T
authors.lastname: Ro
mesh_terms: D000328:Adult; D004192:Discrimination, Psychological; D005246:Feedback; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation; D014473:Unconscious, Psychology; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult