Degraded mapping of disparity tuning in visual cortex explains deficits in binocular depth perception

Abstract

Sensory cortex is highly organized, but the function of this organization is contentious. We show that closing one eye during the developmental critical period in juvenile mice (monocular deprivation) caused lasting impairments in binocular depth perception and disrupted cortical maps of binocular disparity tuning. In normal mice, disparity tuning was concentrated in the central visual field, particularly with respect to azimuth and in higher visual areas (HVAs). Additionally, neurons transitioned from encoding nearer to farther stereoscopic depths from the center toward the peripheral visual field, especially along elevation and within HVAs. Monocular deprivation did not reduce overall disparity selectivity across the neuronal population, but rather weakened the retinotopic and hierarchical organization of disparity tuning and reduced trial-to-trial reliability of neuronal responses. Analysis of single-trial responses from neurons tuned to near disparities showed that this reduced response reliability is sufficient to explain the impaired depth discrimination observed in deprived mice.