title: A common signal detection model accounts for both perception and discrimination of the watercolor effect.
abstract: Establishing the relation between perception and discrimination is a fundamental objective in psychophysics, with the goal of characterizing the neural mechanisms mediating perception. Here, we show that a procedure for estimating a perceptual scale based on a signal detection model also predicts discrimination performance. We use a recently developed procedure, Maximum Likelihood Difference Scaling (MLDS), to measure the perceptual strength of a long-range, color, filling-in phenomenon, the Watercolor Effect (WCE), as a function of the luminance ratio between the two components of its generating contour. MLDS is based on an equal-variance, gaussian, signal detection model and yields a perceptual scale with interval properties. The strength of the fill-in percept increased 10-15 times the estimate of the internal noise level for a 3-fold increase in the luminance ratio. Each observer's estimated scale predicted discrimination performance in a subsequent paired-comparison task. A common signal detection model accounts for both the appearance and discrimination data. Since signal detection theory provides a common metric for relating discrimination performance and neural response, the results have implications for comparing perceptual and neural response functions.
authors.affiliation: CRPCC EA 1285, Université Rennes 2, Rennes,  France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Devinck
authors.forename: Kenneth
authors.initials: K
authors.lastname: Knoblauch
mesh_terms: D000328:Adult; D003118:Color Perception / Q000502:physiology*; D055253:Color Vision / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006801:Humans; D008029:Lighting; D008297:Male; D008959:Models, Neurological; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics; D017603:Signal Detection, Psychological / Q000502:physiology*; D055815:Young Adult