I Visual Cognition: an Introduction*, and by a Grant from the Sloan Foundation Awarded to the Met Center for Cognftive Scr- Encc. I Thank Oolo-0277/84/$19.40 Elsevier Sequoia/printed in the Netherlands

a This article is a tutorial overview of a sample of central issues in visual cognition, focusing on the recognition of shapes and 4h iice representation of objects and spatiai’ relations in perception and imagery. Brief reviews of the state of the art are presented, followed by more extensive presentations of contemporary theories, findings, and open issues. I discuss various theories of shape recognition, such as template, feature, Fourier, structural descrtption, Marr-Nishihara, and massively parallel models, and issues such as the reference frames, primitives, top-down processing, and computational architectures used in spa1 tial cognition. This is followed by a discussion of mental imagery, including conceptua/ issues in imagery research, theories of imagery, imagery and perception, image trans$or.mations, computational complexities of image processing, neuropsychological issues, and possible functions of imagery. Connections between theories of recognition and of imagery, and the relevance of the papers contained in this issue to the topics discussed, are emphasized through-