Dipole Information Complementarity in Discrete 2D Patterns.

An information theoretic approach is used to derive equations describing the dipole information in discrete two-dimensional (2D) patterns. Dipoles are pair-wise, or second-order, interactions of pattern states. It is shown that the basic dipole information equation can be decomposed into two complementary representations of the total information. One of these representations expresses the total information in terms of the sum of two components: the dipole spatial information and the permutation set information. The spatial information component describes the information in the distribution of spatial transitions for each type of color transition. The permutation set information component is a second-order function of the single color probabilities. The second representation is also the sum of two components: the dipole color information and the array information. The dipole color information describes the information in the distribution of color transitions for each possible spatial transition. The array information is a function of the size and geometry of the pattern array. These two representations characterize the total information from complementary perspectives, each emphasizing different aspects of the pattern's structure. Implications of this approach for the understanding of patterns and pattern perception are examined. Copyright 1999 Academic Press.

Detection of three-dimensional structure in moving optical patterns.

Three experiments examined parameters affecting human observers' ability to detect the global three-dimensional (3D) organization of a random-dot display corresponding to the polar projection of a rotating sphere. Results indicate that the detection of 3D structure is critically dependent on the detectability of motion, is disrupted by increased redundant information specifying the two-dimensional location of points in the display, and undergoes a rapidly increasing resistance to the disruptive effects of noise with increasing numbers of frames. These results, in conjunction with earlier findings, are inconsistent with existing theories concerning the perception of three-dimensionality in moving displays, in that they indicate a high degree of visual sensitivity to stimulus organizations with unique topological representations.

Minimal conditions for the visual detection of structure and motion in three dimensions.

Human observers detected the global three-dimensional organization of visual patterns consisting of only two successive frames of randomly positioned dots, corresponding to projections of a rotating sphere. A perfectly coherent sphere yielded a stable perceptual organization that was detected more accurately than other slightly less organized patterns.