Beginning with his doctoral dissertation in 1950 which introduced the study of event perception and the application of vector analysis to perception, Gunnar Johansson has been a seminal figure in the field of perception. His work on biomechanical motion in the 1970s challenged conventional notions and stimulated great interest among experimental psychologists and students of machine vision. In 1989 Johansson published his latest theoretical synthesis, the optic sphere theory, an innovative conceptualization that goes beyond his earlier proposals. This volume presents -- for the first time -- an extensive precis of the out-of-print classic 1950 monograph prepared by Johansson. It also includes a representative set of Johansson's important publications produced over the ensuing four decades. These papers served as the springboard for a set of original essays by a distinguished group of North American and European scientists. Part critical commentary, part elaboration, and part seeking new directions, the entire collection makes for a singularly rich treatment of the perception of objects and events.

Table of Contents:
Contents: Part I:Biography.S. Rogers, Gunnar Johansson: A Practical Theorist. An Interview with William Epstein. Part II:A Selection of Gunnar Johansson's Contributions.G. Johansson, Configurations in Event Perception. G. Johansson, Rigidity, Stability and Motion in Perceptual Space. G. Johansson, Perception of Motion and Changing Form. G. Johansson, On Theories for Visual Space Perception. J.J. Gibson, On Theories for Visual Space Perception. G. Johansson, Visual Perception of Biological Motion and a Model for Its Analysis. G. Johansson, Spatio-Temporal Differentiation and Integration in Visual Motion Perception. G. Johansson, Studies on Visual Perception of Locomotion. G. Johansson, E. Börjesson, Toward a New Theory of Vision. Studies in Wide-Angle Space Perception. G. Johansson, Visual Vector Analysis and the Optic Sphere Theory. Part III:Tracing Gunnar Johansson's Theoretical Development.W. Epstein, Looking at Perceptual Theory Through a Johansson Lens. G. Johansson, Comments on Epstein: Looking at Perceptual Theory Through a Johansson Lens. Part IV:Applied Research.K. Rumar, Human Factors in Road Traffic. H. Leibowitz, A Note on the Synergy Between Basic and Applied Research. Part V:Commentaries on Selected Aspects of Gunnar Johansson's Contributions.Section A:Vector Analysis.J.J. Koenderink, Vector Analysis. S.S. Bergström, Can the Johansson Vector Analysis Be Applied to the Perception of Illumination, Color and Depth? J.S. Lappin, Seeing Structure in Space-Time. S. Runeson, Perception of Biological Motion: The KSD-Principle and the Implications of the Distal Versus Proximal Approach. Section B:Perceptual Processing.G. Jansson, Perceived Bending Motion, the Principle of Minimum Object Change, and the Optic Sphere Theory. J. Hochberg, Vector Analysis, Perceptual Intention, and the Hidden Rules of Visual Perception. M.L. Braunstein, Decoding Principles, Heuristics and Inference in Visual Perception. Section C:Vection and Locomotion.R. Held, H. Leibowitz, The Significance of Vection: Thoughts Provoked by Gunnar Johansson's Studies on Visual Perception of Locomotion. C. von Hofsten, D.N. Lee, Measuring With the Optic Sphere. Section D:Optic Sphere Theory.J.T. Todd, On the Optic Sphere Theory and the Nature of Visual Information. E. Börjesson, The Optic Sphere Theory as a Slant Determining Mechanism. Part VI:Concluding Remarks.G. Johansson, Personal Comments. G. Johansson, Bibliography 1950-1993.