SUNY Optometry Distinguished Professor Leads Team on Study of Myopia
New York, NY: SUNY College of Optometry is honored and pleased to announce the publication of an article in The Journal of Neuroscience on Tuesday, November 28, 2023 from research that was conducted by PhD Candidate Sabina Poudel and collaborators in the laboratories of Dr. Jose-Manuel Alonso at the SUNY Optometry. The article is entitled, “Contrast Sensitivity of ON and OFF Human Retinal Pathways in Myopia.”
In this new paper, SUNY Optometry scientists demonstrate that ON pathways are also more sensitive than OFF pathways in the human eye, but this higher sensitivity comes with a cost. It makes ON pathways vulnerable to loss of image sharpness under low light.
“Across the entire animal kingdom, visual images are processed by two major neuronal pathways that extract light and dark stimuli from visual scenes – ON (light on) and OFF (light off) pathways,” said Dr. Jose-Manuel Alonso. “Light stimuli are brighter than their background like a white cloud in a gray sky whereas dark stimuli are darker than the background like a black bird in a blue sky. The two pathways can extract stimuli with different contrasts but some pathways are more sensitive than others. In carnivores and rodents, ON pathways are more sensitive to low contrasts than OFF pathways and, in our brightly-illuminated world, low contrasts are also more abundant among light than dark stimuli.”
The abstract, published in The Journal of Neuroscience, can be found below.
The human visual cortex processes light and dark stimuli with ON and OFF pathways that are differently modulated by luminance contrast. We have previously demonstrated that ON cortical pathways have higher contrast sensitivity than OFF cortical pathways and the difference increases with luminance range (defined as the maximum minus minimum luminance in the scene). Here, we demonstrate that these ON-OFF cortical differences are already present in the human retina and that retinal responses measured with electroretinography are more affected by reductions in luminance range than cortical responses measured with electroencephalography. Moreover, we show that ON-OFF pathway differences measured with electroretinography become more pronounced in myopia, a visual disorder that elongates the eye and blurs vision at far distance. We find that, as the eye axial length increases across subjects, ON retinal pathways become less responsive, slower in response latency, less sensitive, and less effective and slower at driving pupil constriction. Based on these results, we conclude that myopia is associated with a deficit in ON pathway function that decreases the ability of the retina to process low contrast and regulate retinal illuminance in bright environments.
For more information about this study, a press packet can be downloaded here: www.dropbox.com
Media Contact: Dawn Rigney (Vice President and PIO, 212-938-5601, drigney@sunyopt.edu)
Jose-Manuel Alonso (correspondence author, 212-938-5573, jalonso@sunyopt.edu)
Rob Rosiello (Associate Director of Communications and Marketing, 212-938-5753, RRosiello@sunyopt.edu)
State University of New York, College of Optometry
33 West 42nd street, New York, NY 10036
FOR IMMEDIATE RELEASE: Tuesday, November 28, 2023
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About SUNY Optometry
Founded in 1971 and located in New York City, the State University of New York College of Optometry is a leader in education, research, and patient care, offering the Doctor of Optometry degree as well as MS and PhD degrees in vision science. The College conducts a robust program of basic, translational and clinical research and has 65 affiliated clinical training sites as well as an on-site clinic, the University Eye Center. SUNY Optometry is regionally accredited by the Commission on Higher Education of the Middle States Association of Colleges and Secondary Schools; its four-year professional degree program and residency programs are accredited by the Accreditation Council on Optometric Education of the American Optometric Association. All classrooms, research facilities and the University Eye Center, which is one of the largest
optometric outpatient facilities in the nation, are located on 42nd Street in midtown Manhattan. To learn more about SUNY Optometry, visit www.sunyopt.edu.