title: Response priming driven by local contrast, not subjective brightness.
abstract: We demonstrate qualitative dissociations of brightness processing in visuomotor priming and conscious vision. Speeded keypress responses to the brighter of two luminance targets were performed in the presence of preceding dark and bright primes (clearly visible and flanking the targets) whose apparent brightness values were enhanced or attenuated by a visual illusion. Response times to the targets were greatly affected by consistent versus inconsistent arrangements of the primes, relative to the targets (response priming). Priming effects could systematically contradict subjective brightness matches, such that one prime could appear brighter than the other but could prime as if it were darker. Systematic variation of the illusion showed that response-priming effects depended only on local flanker-background contrast, not on the subjective appearance of the flankers. Our findings suggest that speeded motor responses, as opposed to conscious perceptual judgments, access an early phase of lightness and brightness processing prior to full lightness constancy.
authors.affiliation: Faculty of Social Sciences, Psychology I, University of Kaiserslautern, Erwin-Schrödinger-Str. Geb. 57, D-67663 Kaiserslautern, Germany. thomas.schmidt@sowi.uni-kl.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Schmidt
authors.forename: Sandra
authors.initials: S
authors.lastname: Miksch
authors.forename: Lisa
authors.initials: L
authors.lastname: Bulganin
authors.forename: Florian
authors.initials: F
authors.lastname: Jäger
authors.forename: Felix
authors.initials: F
authors.lastname: Lossin
authors.forename: Joline
authors.initials: J
authors.lastname: Jochum
authors.forename: Peter
authors.initials: P
authors.lastname: Kohl
mesh_terms: D000328:Adult; D001288:Attention; D015350:Contrast Sensitivity; D003463:Cues; D003867:Depth Perception; D004192:Discrimination, Psychological; D005260:Female; D006801:Humans; D007600:Judgment; D008297:Male; D009949:Orientation; D010364:Pattern Recognition, Visual; D011597:Psychomotor Performance; D011601:Psychophysics; D011930:Reaction Time; D055815:Young Adult