title: Context-dependent brightness priming occurs without visual awareness.
abstract: Our visual systems account for stimulus context in brightness perception, but whether such adjustments occur for stimuli that we are unaware of has not been established. We therefore assessed whether stimulus context influences brightness processing by measuring unconscious priming with metacontrast masking. When a middle-gray disk was presented on a darker (or brighter) background, such that it could be consciously perceived as brighter (or darker) via simultaneous brightness contrast (SBC), reaction times were significantly faster to a bright (or dark) annulus than to a dark (or bright) annulus. We further show that context-dependent brightness priming does not correlate with visibility using an objective measure of awareness (Experiment 1) and that context-dependent, but not context-independent brightness priming, occurs equally strongly for stimuli below or above the subjective threshold for awareness (Experiment 2). These results suggest that SBC occurs at early levels of visual input and is not influenced by conscious perception.
authors.affiliation: Department of Psychology, The City College, City University of New York, North Academic Center (NAC), Room 7/120, 160 Convent Avenue, New York, NY 10031, USA.
authors.forename: Marjan
authors.initials: M
authors.lastname: Persuh
authors.forename: Tony
authors.initials: T
authors.lastname: Ro
mesh_terms: D000293:Adolescent; D000328:Adult; D001364:Awareness; D015350:Contrast Sensitivity; D005260:Female; D006801:Humans; D008297:Male; D009518:New York; D010470:Perceptual Masking; D011930:Reaction Time; D060865:Repetition Priming; D014796:Visual Perception; D055815:Young Adult