Motion Detection Mechanisms

This review discusses theoretical, behavioral, and physiological studies of motion mechanisms. The three main schemes for motion detection (space-time correlation, orientation, and gradients) are contrasted using experimental data from insects, rabbits, cats, monkeys, and humans. These schemes provide a basic understanding of the organization of many neural motion detection systems. However, few neural systems are pure implementations of any of these three detection schemes. It is suggested that using a mixture of motion detection mechanisms may be advantageous to a neural system faced with the difficult, but important task of detecting motion under widely varying conditions.