John H.R. Maunsell

Leader in understanding information processing in the brain. Formulated original version of now-well-known scheme showing a hierarchy of visual cortical areas, which provided an important framework for understanding the functional organization of visual cortex. With Peter Schiller, characterized separate visual ON and OFF pathways, and role of these and other parallel pathways in processing specific attributes of visual stimuli. Work provided foundation for much of our current understanding of hierarchical and parallel organization in the visual system. Recently, using monkeys trained to perform sophisticated behavioral tasks, measured how attention to a visual stimulus affects activity of cortical neurons that represent it. Experiments revealed that neuronal signals even in relatively early processing stages are robustly and selectively enhanced when the animal attends to the stimulus they represent. Showed that attention affects inter-neuronal relationships to enhance the representation of stimuli by populations of neurons. These findings have significantly advanced understanding of cortical processing of sensory information.