Luminance

Natural vision involves encoding complex inputs with spatial and temporal variations in luminance and contrast, which vary widely within and across visual scenes. This engages multiple interacting neural circuits that process these features and implement functions like gain control, decorrelation, and contextual prediction. One hallmark of such circuit interactions at the cortical level is that they give rise to fast oscillatory dynamics, which are reflected in the local field potential (LFP). While recent studies in mice have linked oscillations driven by artificial stimuli to specific thalam

…in lit environments and under various luminance levels has been well-studied in many mammalian species. However, how the functionally distinct superficial and deep cortical layers of the V1 encode abrupt and sustained changes in light conditions in freely exploring animals remains unclear. To address this question, we recorded neuro

How does the visual system adapt when the amount of light in the scene changes, such as when an animal leaves a shaded area or when night turns to day? As light levels increase and the relative amount of noise in the scene decreases, efficient coding theory predicts a transition in sensory processing. At low light levels, sensory systems should integrate spatial and temporal information, while at high light levels, neural processing should differentiate incoming signals to subtract predictive components. Previous experimental work has shown that, indeed, the center-surround structure of spatia

…we have much less understanding of how luminance is combined binocularly, both in the cortex and in subcortical structures that govern pupil diameter. Here I will describe the results of experiments using a novel combined EEG and pupillometry paradigm to simultaneously index binocular combination of luminance flicke

…which differed in spatial features, luminance, orientation, or contextual conditions. Only weak correlations were o

…have long realized that color and luminance can play independent roles in visual perception. Picasso said, "Colors are only symbols. Reality is to be found in luminance alone." This observation has a parallel in the functional subdivision of our visual systems, where color and luminance are processed by the evolutionarily newer

Stereopsis – deriving information about distance by comparing views from two eyes – is widespread in vertebrates but so far known in only class of invertebrates, the praying mantids. Understanding stereopsis which has evolved independently in such a different nervous system promises to shed light on the constraints governing any stereo system. Behavioral experiments indicate that insect stereopsis is functionally very different from that studied in vertebrates. Vertebrate stereopsis depends on matching up the pattern of contrast in the two eyes; it works in static scenes, and may have evolved

…a solution by propagating a corrective luminance-sensitive signal to higher pro