A common signal detection model accounts for both perception and discrimination of the watercolor effect

• Published in: Journal of vision (Charlottesville, Va.) Vol. 12; no. 3; p. 19
• Main Authors: Devinck, Frédéric, Knoblauch, Kenneth
• Format: Journal Article
• Language: English
• Published: United States Association for Research in Vision and Ophthalmology 21-03-2012
• Subjects: Adult; Color Perception - physiology; Color Vision - physiology; Discrimination (Psychology) - physiology; Female; Humanities and Social Sciences; Humans; Lighting; Male; Models, Neurological; Photic Stimulation - methods; Psychology; Psychophysics; Signal Detection, Psychological - physiology; Young Adult
• ISSN: 1534-7362; 1534-7362
• DOI: 10.1167/12.3.19

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.