This chapter emphasized motion perception's many varied contributions, from defining the three-dimensional shape of moving objects and providing information that we use in locomoting to guiding the eye movements that we use as we explore the world. The chapter described the neural basis of movement perception and the circuitry used to extract motion signals. It explained how limitations of this circuitry produced a dependence on configural properties, including the shape of the aperture within which an object moves. You read about two theoretically significant illusions of motion perception, namely apparent motion and motion aftereffect. After exploring parallels between the properties of natural events and the neural mechanisms designed to register those events, the chapter ended with a discussion of important higher-order influences on motion, including attention.

This chapter concludes our survey of visual qualities that enable you to appreciate the various biologically important aspects of the world. Next, we turn to other senses that also provide vital information about that world. We begin with the ear and hearing.