Parietal control of attentional guidance: the significance of sensory, motivational and motor factors.

The lateral intraparietal area (LIP), a portion of monkey posterior parietal cortex, has been implicated in spatial attention. We review recent evidence showing that LIP encodes a priority map of the external environment that specifies the momentary locus of attention and is activated in a variety of behavioral tasks. The priority map in LIP is shaped by task-specific motor, cognitive and motivational variables, the functional significance of which is not entirely understood. We suggest that these modulations represent teaching signals by which the brain learns to identify attentional priority of various stimuli based on the task-specific associations between these stimuli, the required action and expected outcome.