Upcoming Research Talks
April 17, 2024
1:00 p.m., CVS Large Conference Room, URMC G-4104
Research Talk: Sabina Poudel, SUNY College of Optometry (Postdoctoral candidate talk)
Functional contributions of ON and OFF pathways to human vision
The human visual system processes light and dark stimuli in visual scenes with separate ON and OFF neuronal pathways, which begins in the retina at the first synapse from photoreceptors and bipolar cells. Traditionally, ON and OFF pathways were treated as mirror versions of each other responding to opposite light-dark polarities but otherwise same. Contrary to this view, growing evidences indicate the differences between ON and OFF pathways extend beyond a flip of polarity depending on the spatiotemporal properties of the visual input. In my thesis, I investigate how ON and OFF pathways are stimulated in humans under different visual tasks and measure the contrast response functions of retinal ON and OFF pathways in humans.
In the first chapter, I record visual images and visuomotor activity when human subjects performed two visual tasks, reading and walking indoors, wearing Tobii Pro Glasses 2. I developed metrics to measure ON and OFF pathway stimulation in different portions of the visual scene (e.g. fovea and visual periphery) for different stimulation parameters (e.g. spatial contrast, temporal contrast, spatial skewness, temporal skewness) and quantify sensorimotor activity (e.g. pupil dynamics, blink frequency/duration, fixation duration). I demonstrate pronounced task differences in the stimulation balance of ON and OFF visual pathways. Reading reduces central visual stimulation of ON visual pathways and decreases visuomotor activity and reflexes domination by ON visual pathways. These results could explain why the risk of myopia progression, a visual disorder that blurs vision at far distances, increases with time spent reading and decreases with outdoor activities, thus supporting the hypothesis that myopia progression is driven by poor stimulation of ON visual pathways that disrupt the ON/OFF response balance.
In the second chapter, I use electroretinography (ERG) to measure the contrast response functions of ON and OFF retinal pathways in humans and further investigate if two pathways are differently affected by myopia. We have previously demonstrated that cortical ON and OFF pathways have different contrast sensitivity, and the difference increases with luminance range. Here, I demonstrate that these ON-OFF differences are already present in the human retina and are affected by myopia. My measurements demonstrate that myopia is associated with a deficit in ON retinal pathway function that reduces the retinal ability at signaling low contrast and regulating retinal illuminance in bright environments. These results could lead to novel approaches of myopia control based on ON-pathway stimulation.
Past Research Talks
2024
March 20, 2024
CVS Research Talk: Richard Lange, Rochester Institute of Technology
What Bayes can and cannot tell us about the principles of vision
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February 22, 2024
CVS Research Talk: Greg Field, Associate Professor of Ophthalmology, University of California, Los Angeles
A Theoretical Underpinning for Cell Type Diversity, Mosaic Organization, and Adaptation
2023
November 2, 2023
BCS/CVS Research Talk: Peter Bex, Department of Psychology, Northeastern University
Assessment and Rehabilitation in Strabismic Amblyopia
November 1, 2023
CVS Research Talk: Alex Levin, University of Rochester Medical Center
Is affordable accessible gene therapy for inherited retinal disease possible?
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October 25, 2023
CVS Research Talk: Len Zheleznyak, Clerio Vision and University of Rochester
An optical approach to myopia control in children
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October 25, 2023
CVS Research Talk: Rachel Wozniak, University of Rochester Medical Center
Bacterial Keratitis: Pathogenesis and Therapeutics
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October 2, 2023
Research Talk: Geoffrey Boynton, University of Washington
Pulse trains to percepts: Using virtual patients to describe the perceptual experience generated by visual prosthetics
August 30, 2023
Research Talk: Yuhao Zhu, UR Computer Science, 2023/24 BCS Bridging Fellow
Harvesting Computer Science-Vision Science Symbiosis: A Case Study on Color Vision
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May 2, 2023
Research Talk: Sally McFadden, University of Newcastle, Australia
Retinal pathways underlying myopia in the guinea pig
April 20, 2023
NEUROYES Seminar: Ipshita Zutshi, NYU School of Medicine
Extrinsic control and intrinsic computation in the hippocampal CA1 network
April 18, 2023
Combined FEI/Optics/Neuroscience Candidate Talk: Sara Patterson, Postdoctoral Fellow, University of Rochester
Linking rare primate ganglion cells to downstream visual functions
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March 2, 2023
NEUROYES Seminar: Sunday M. Francis, NIH/NIMH
Transdiagnostic Targets: Compulsivity in Neurodevelopmental Disorders
February 27, 2023
Research Talk: Wilson Geisler, University of Texas at Austin
Identifying Targets in Noise and Natural Backgrounds
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February 1, 2023
Research Talk: Michael Murdoch, Rochester Institute of Technology
Color Appearance in Optical See-Through Augmented Reality
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January 26, 2023
NEUROYES Seminar: Shahzad S. Khan, Stanford University
Consequences of LRRK2 hyperactivity on nigrostriatal circuits
2022
December 7, 2022
Research Talk: Chris Kanan, Department of Computer Science
Advancing Artificial Intelligence and Machine Perception by Studying Cognitive Science
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November 30, 2022
Research Talk: Benjamin Suarez-Jimenez, Department of Neuroscience
Brain Mechanism of Discrimination Learning: Spatial Navigation and Attention
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October 27, 2022
NEUROYES Seminar: Tahra Eissa, University of Colorado Boulder
The impacts of environmental inference on human decision-making
August 3, 2022
CVS Research Talk: Colin Palmer, School of Psychology, UNSW Sydney, Australia /Department of Psychology, National University of Singapore
Are you looking at me? Visual mechanisms underlying the perception of eye gaze