GEON THEORY AS AN ACCOUNT OF SHAPE-RECOGNITION IN MIND AND BRAIN

In a fraction of a second humans are able to comprehend novel images of objects and scenes. Indeed, the human represents the only existence proof that a general shape recognizer is even possible. Geon theory offers an account of this phenomenon characterized by four general assumptions: a) Objects are represented as an arrangement of simple convex or singly concave parts (geons), b) The geons can be distinguished by binary contrasts (differences) in viewpoint invariant properties, such as straight vs, curved, rather than metric properties such as degree of curvature, c) The relations among the geons are explicit, such as PERPENDICULAR-TO or TOP-OF, as part of a structural description, rather than implicit in a coordinate space, and d) A relatively small number of geons is sufficient. Recent research evaluating these assumptions is reviewed.