All animals that can form images in their retinas, from flies to humans, need ON and OFF brain pathways to process light and dark features in visual scenes. The traditional textbook view is that these ON and OFF pathways fully converge in visual cortex to make neurons selective to stimulus orientation but invariant to stimulus polarity and spatial phase. Against this traditional view, our recent work demonstrates that ON and OFF pathways segregate in visual cortex, specialize in different spatiotemporal functions, and process images relatively independently from each other. In addition, our preliminary results indicate that ON and OFF cortical pathways respond very differently to changes in luminance range, which varies continuously in our visual environment from sunrise to sunset. Based on our results, we hypothesize that luminance perception originates from the interaction between two separate and relatively independent ON and OFF pathways that are exquisitely matched to the statistics of light and dark features in natural scenes. This new understanding of ON and OFF cortical processing has important implications for human luminance perception, image brain processing analysis and could help improve the diagnostic tools available to manage treatment in human visual disease. In this proposal, we will investigate how ON and OFF cortical pathways interact to generate luminance perception, and how these interactions vary with background luminance, luminance range and the rod/cone retinal ratio available to sample the images. We will then use all these measurements to develop models that replicate human luminance perception more accurately than in the past and new diagnostic tools that measure human ON and OFF visual function in diseases that affect the retina (e.g. glaucoma) and visual cortex (e.g. amblyopia).
Human vision depends on the functional integrity of two major information pathways that originate at the very first synapse of the visual brain and signal the presence of light and dark stimuli in visual scenes, the ON and OFF pathways. Recent results from our laboratory indicate that loss of visual acuity under low light or optical blur affects the cortical circuitry of the ON pathway more than the OFF pathway. They also demonstrate that the ON pathway is more vulnerable to visual diseases that compromise visual spatial resolution such as amblyopia. In this proposal, we will investigate the relative contribution from ON and OFF pathways to human luminance perception and will develop new diagnostic tools to measure ON and OFF visual function and guide treatments in visual disease.
|Luo-Li, Gloria; Mazade, Reece; Zaidi, Qasim et al. (2018) Motion changes response balance between ON and OFF visual pathways. Commun Biol 1:60|
|Kremkow, Jens; Alonso, Jose-Manuel (2018) Thalamocortical Circuits and Functional Architecture. Annu Rev Vis Sci 4:263-285|
|Alonso, Jose Manuel (2018) Motion processing picks up speed in the brain. Nature 558:38-39|
|Pons, Carmen; Mazade, Reece; Jin, Jianzhong et al. (2017) Neuronal mechanisms underlying differences in spatial resolution between darks and lights in human vision. J Vis 17:5|
|Mazade, Reece; Alonso, Jose Manuel (2017) Thalamocortical processing in vision. Vis Neurosci 34:E007|
|Koch, Erin; Jin, Jianzhong; Alonso, Jose M et al. (2016) Functional implications of orientation maps in primary visual cortex. Nat Commun 7:13529|
|Kremkow, Jens; Perrinet, Laurent U; Monier, Cyril et al. (2016) Push-Pull Receptive Field Organization and Synaptic Depression: Mechanisms for Reliably Encoding Naturalistic Stimuli in V1. Front Neural Circuits 10:37|
|Kremkow, Jens; Jin, Jianzhong; Wang, Yushi et al. (2016) Principles underlying sensory map topography in primary visual cortex. Nature 533:52-7|
|Wool, Lauren E; Komban, Stanley J; Kremkow, Jens et al. (2015) Salience of unique hues and implications for color theory. J Vis 15:|
|Zhao, Linxi; Sendek, Caroline; Davoodnia, Vandad et al. (2015) Effect of Age and Glaucoma on the Detection of Darks and Lights. Invest Ophthalmol Vis Sci 56:7000-6|
Showing the most recent 10 out of 38 publications