M. F. Schulz*+, M. A. Peterson+, T. Sanocki*, E. W. Sellers*
*University of South Florida, +University of Arizona

Abstract:
We used priming to investigate whether similarity grouping occurs before or
after color constancy. In ambiguous masked prime displays, a central
column of elements appeared behind a transparent surface. The central
column could group with elements on the right or left depending on whether
grouping was based on a pre- or post- constancy representation of color.
Participants reported the grouping of unambiguous target displays. No
transparency was present in targets, so the central elements were the same
color as either the right or left elements. At short prime durations, responses
were faster when the target grouping matched the pre-constancy prime
grouping. At long prime durations, responses were faster when the target
grouping matched the post-constancy prime grouping. Thus, grouping can
operate on both pre- and post-constancy representations.