Vision and the Timing of Actions

To produce even the simplest organised movement, the central nervous system must generate a pattern of motor activity in which changes in the strengths of contractions of different muscles are precisely timed in relation to one another. Almost always, this pattern must be adjusted to the surrounding environment using visual and other sensory information. These adjustments may alter the path of the body or a limb through space, and we saw in Chapter 11 some ways in which this can be achieved through vision. In this chapter, we will consider a different aspect of the visual control of action, asking how the timing of movements is controlled in relation to events unfolding around an animal or person.