Spatial context non-uniformly modulates inter-laminar information flow in the primary visual cortex.

Our visual experience is a result of the concerted activity of neuronal ensembles in the sensory hierarchy. Yet, how the spatial organization of objects influences this activity remains poorly understood. We investigate how inter-laminar information flow within the primary visual cortex (V1) is affected by visual stimuli in isolation or with flankers at spatial configurations that are known to cause non-uniform degradation of perception.

Widespread receptive field remapping in early primate visual cortex.

Predictive remapping of receptive fields (RFs) is thought to be one of the critical mechanisms for enforcing perceptual stability during eye movements. While RF remapping has been observed in several cortical areas, its role in early visual cortex and its consequences on the tuning properties of neurons have been poorly understood. Here, we track remapping RFs in hundreds of neurons from visual area V2 while subjects perform a cued saccade task.

Non-uniform contextual interactions in the visual cortex place fundamental limits on spatial vision.

A prevailing assumption in our understanding of how neurons in the primary visual cortex (V1) integrate contextual information is that such processes are spatially uniform. Conversely, perceptual phenomena such as visual crowding, the impaired ability to accurately recognize a target stimulus among distractors, suggest that interactions among stimuli are distinctly non-uniform. Prior studies have shown flankers at specific spatial geometries exert differential effects on target perception.

Laminar mechanisms of saccadic suppression in primate visual cortex.

Saccadic eye movements are known to cause saccadic suppression, a temporary reduction in visual sensitivity and visual cortical firing rates. While saccadic suppression has been well characterized at the level of perception and single neurons, relatively little is known about the visual cortical networks governing this phenomenon. Here we examine the effects of saccadic suppression on distinct neural subpopulations within visual area V4.

WIDESPREAD RECEPTIVE FIELD REMAPPING IN EARLY VISUAL CORTEX.

Our eyes are in constant motion, yet we perceive the visual world as stable. Predictive remapping of receptive fields is thought to be one of the critical mechanisms for enforcing perceptual stability during eye movements. While receptive field remapping has been identified in several cortical areas, the spatiotemporal dynamics of remapping, and its consequences on the tuning properties of neurons, remain poorly understood.