title: Detection of change in shape: an advantage for concavities.
abstract: Shape representation was studied using a change detection task. Observers viewed two individual shapes in succession, either identical or one a slightly altered version of the other, and reported whether they detected a change. We found a dramatic advantage for concave compared to convex changes of equal magnitude. Observers were more accurate when a concavity along the contour was introduced, or removed, compared to a convexity. This result sheds light on the underlying representation of visual shape, and in particular the central role played by part-boundaries. Moreover, this finding shows how change detection methodology can serve as a useful tool in studying the specific form of visual representations.
authors.affiliation: Department of Psychology, Center for Cognitive Science, Rutgers University - New Brunswick, Piscataway, NJ 08854-8020, USA. elanbz@ruccs.rutgers.edu
authors.forename: Elan
authors.initials: E
authors.lastname: Barenholtz
authors.forename: Elias H
authors.initials: EH
authors.lastname: Cohen
authors.forename: Jacob
authors.initials: J
authors.lastname: Feldman
authors.forename: Manish
authors.initials: M
authors.lastname: Singh
mesh_terms: D004192:Discrimination, Psychological; D005556:Form Perception; D006801:Humans; D013647:Task Performance and Analysis