title: Subjective visibility depends on level of processing.
abstract: Is visual awareness graded or binary? Experimental work has provided support for both possibilities, leading to two coexisting but contradictory theoretical accounts. Here we propose a promising candidate factor through which to integrate both accounts: the depth of stimulus processing required by the task. We compared color identification (a low-level task) with numerical judgements (a high-level task) performed on the very same colored number stimuli. Psychophysical curves were analyzed for both objective discrimination performance and subjective visibility ratings on a trial-by trial basis. We observed a graded relationship between stimulus duration and visibility in the low-level task, but a more non-linear relationship in the high-level task. Both patterns of results have previously been consistently associated with the graded and the dichotomous account, respectively. Follow-up experiments that manipulate the level of processing can further unify previously inconsistent results, thus integrating two major theories of visual awareness.
authors: ULB Neuroscience Institute (UNI), Université Libre de Bruxelles, Building C / Campus Erasme, CP 602, 808, Route de Lennik, 1070 Bruxelles, Belgium; Center for Research in Cognitive Neurosciences (CRCN), Université Libre de Bruxelles, CP 191, Avenue F.D. Roosevelt 50, 1050 Bruxelles, Belgium; Consciousness, Cognition and Computation Group, Université Libre de Bruxelles CP 191, Avenue F.-D. Roosevelt, 50, 1050 Bruxelles, Belgium. Electronic address: bwindey@ulb.ac.be.
authors: Bert
authors: B
authors: Windey
authors: Wim
authors: W
authors: Gevers
authors: Axel
authors: A
authors: Cleeremans
mesh_terms: D001364:Awareness / Q000502:physiology*; D003118:Color Perception / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D011601:Psychophysics; D013997:Time Factors; D014785:Vision, Ocular / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Awareness; Consciousness; Dichotomous; Graded; Psychophysics; Vision