The operation of the visual system in relation to action.

Neurophysiologists studying the visual representation of the world in the parietal lobe generally find that it is based in a gaze-centred (retinotopic) frame. Students of orientation, however, find that the brain also contains a more panoramic egocentric representation that allows appropriate motor actions to take place independent of the orientation of the eyes and head. This representation can operate temporarily without visual input, but is updated from the vestibular system and from other modalities. In this minireview, I shall consider how these two representations are kept aligned with each other, and how they relate to the organisation of motor actions and to the phenomenal world that we see.