Introduction to Brain mechanisms of selective perception and action. Proceedings of a Discussion Meeting held at the Royal Society of London on 19 and 20 November 1997.

The world is full of objects. Some may be static, others not. Some may be partially occluded, others standing alone. Some may emit sounds, others not. Some we may be touching (hands resting on a table), others out of reach. At a sensory level, the means by which the world comes to be organized into objects is a far from trivial problem, since stimulus information is typically ambiguous as to which local parts of a scene ‘belong’ together. It is also unclear how different forms of sensory information combineödoes each sense operate independently, or is information integrated in forms of multi-modal representation (Driver, this issue)? Furthermore, the behavioural responses we are equipped to make are inherently limited.We may only name one object at a time; we can reach at most to two objects. The information available to our senses needs to be selected, so that only elevant parts of the world are represented for action. In this way, action may interact in important ways with perceptual processing. Scenes may be parsed in different ways according to our intended behaviour. Perception and action may be linked through processes of selective attention (Milner, this issue; Tipper et al., this issue).