Towards the Neural Basis of Spatial Attention: Studies in Monkey and Man

Our capacity for the processing of information is limited. At any time, only a small part of the information available at the level of the sensory surfaces is perceived consciously and able to influence our behaviour. The term attention captures the cognitive functions which are responsible for filtering out unwanted information and bringing to consciousness what is relevant for the organism. Our brain continuously assigns priority to some aspects of sensory information over others and this selection is likely to determine which of the signals will gain entry to consciousness and to memory and will influence our overt behaviour and our trains of thoughts. In this review, we address two aspects of the functional architecture of attention; first, the relationship between attention shifting and eye movements and, secondly, the question of how attention is guided under natural conditions and how it helps us to contribute to social interactions. We try to justify the conclusion that the common substrate of attention shifting and eye movements posited by the 'pre-motor theory of attention' is the superior colliculus. We also discuss recent comparative work on the role of the eyes of others in the guidance of attention and how this 'gaze following' may allow us to develop a 'theory of mind'.