Separating perceptual and decisional attention processes in the identification and categorization of integral-dimension stimuli.
Four observers performed matching, identification, and categorization with stimuli that varied along the integral dimensions: brightness and saturation. General recognition theory (F. G. Ashby & J. T. Townsend, 1986) was applied to quantify the separate influences of perceptual and decisional processes within and across tasks, with a focus on separating perceptual from decisional attention processes. Good accounts of the identification data were obtained from perceptual matching representation. This perceptual representation provided a good account of the categorization data, except when decisional selective attention to 1 stimulus dimension was required. Decisional selective attention reduced the attended-dimension perceptual variance relative to the unattended-dimension perceptual variance, with a larger reduction resulting when brightness, as opposed to saturation was attended. Implications for color vision research are discussed.
Maddox
W Todd
WT
Department of Psychology, University of Texas, Austin 78712, USA. maddox@psy.utexas.edu
Dodd
Jeffrey L
JL
D001288:Attention; D003657:Decision Making; D006801:Humans; D008960:Models, Psychological; D021641:Recognition, Psychology; D014796:Visual Perception