Neural Circuits That Mediate Selective Attention: A Comparative Perspective.

Selective attention is central to cognition. Dramatic advances have been made in understanding the neural circuits that mediate selective attention. Forebrain networks, most elaborated in primates, control all forms of attention based on task demands and the physical salience of stimuli. These networks contain circuits that distribute top-down signals to sensory processing areas and enhance information processing in those areas. A midbrain network, most elaborated in birds, controls spatial attention. It contains circuits that continuously compute the highest priority stimulus location and route sensory information from the selected location to forebrain networks that make cognitive decisions. The identification of these circuits, their functions and mechanisms represent a major advance in our understanding of how the vertebrate brain mediates selective attention.