Abstract

Milner and Goodale review a wealth of evidence, much of it from their own research, showing that visually guided behavior and perception are controlled by two separate and quasi-independent 'visual brains'. Early evidence showed that motor ability was sometimes preserved despite simultaneous perceptual illusions, and work with patients has differentiated the two systems neurologically. Of the two visual systems, the motor system is less well known: it has a body-based frame of reference, but no memory and limited pattern-recognition capacity.