Laminar segregation of sensory coding and behavioral readout in macaque V4

Significance We show evidence of a division of labor between neurons recorded within the superficial and deep layers of visual cortex in sensory coding and behavior. Neurons within the superficial layers of extrastriate area V4 outperformed their deep layer counterparts in coding the shape of visual stimuli, both in latency and accuracy. In contrast, neurons within the deep layers outperformed their superficial layer counterparts in the coding of selective attention and the planning of eye movements, particularly the latter. The results suggest that a general pattern may exist across sensory neocortex. Neurons in sensory areas of the neocortex are known to represent information both about sensory stimuli and behavioral state, but how these 2 disparate signals are integrated across cortical layers is poorly understood. To study this issue, we measured the coding of visual stimulus orientation and of behavioral state by neurons within superficial and deep layers of area V4 in monkeys while they covertly attended or prepared eye movements to visual stimuli. We show that whereas single neurons and neuronal populations in the superficial layers conveyed more information about the orientation of visual stimuli than neurons in deep layers, the opposite was true of information about the behavioral relevance of those stimuli. In particular, deep layer neurons encoded greater information about the direction of planned eye movements than superficial neurons. These results suggest a division of labor between cortical layers in the coding of visual input and visually guided behavior.