New study connects indoor visual habits to increasing myopia rates

A newly published study¹ describes a hypothesis that may explain how myopia is enhanced in humans. Namely, accommodative pupil constriction drives myopia progression by reducing retinal illumination, according to Urusha Maharjan, OD, lead author and PhD candidate from the Department of Biological and Vision Sciences, State University of New York (SUNY) Optometry, New York. She was joined in this study by investigators from the Laboratory of Neural Systems, The Rockefeller University, New York, and the Center for Visual Science, University of Rochester, Rochester, NY.

One recent theory about the development and progression of myopia is the amount of time individuals spend engaged in using electronic screens. The current study suggests that myopia “may be driven less by screens themselves and more by a common indoor visual habit: prolonged close-up focus in low-light environments, which limits how much light reaches the retina,” according to a press release from the SUNY College of Optometry.

This new hypothesis may explain, they pointed out, why near work and dim indoor lighting, use of atropine drops, multifocal lenses, and outdoor time seem to impact myopia progression.

In their new study, the investigators sought to investigate how the ON and OFF visual pathways contribute to accommodative eye vergence and pupil constriction in the human visual system.

As they explained, the visual pathways are part of a complex visual system. “Visual information is processed in the retina by the ON and OFF visual pathways that respond to light and dark stimuli² and remain segregated throughout the visual cortex.^3,4 In addition to differences in light-dark polarity preference, the ON and OFF pathways also differ in contrast sensitivity,^5-11 spatiotemporal resolution,^6,8,12-14 binocular integration,^15-17 and vulnerability to visual diseases that affect refractive error such as myopia (nearsightedness),^9,18-23” they explained.

Maharjan and colleagues studied how the ON and OFF human visual pathways impact visual accommodation by measuring the visuomotor responses to defocused light and dark stimuli in human subjects. With one eye occluded, they fixated on a small square through a lens that could be tuned electrically to induce -5 diopters of optical defocus in the fixating eye; the subjects brought the square into focus by increasing the power of the crystalline lens, ie, by accommodation.

“The increase in lens accommodation constricted the pupils of both eyes and made the occluded eye turn inward as if the stimulus was approaching the observer. The difference in horizontal gaze between the fixating and occluded eyes provided a measurement of accommodative eye vergence, which is the change in eye vergence caused by the adjustment of eye refractive power. the investigators explained.²⁴

The investigators suggest that the “excessive accommodative pupil constriction that we demonstrated could potentially weaken the ON pathway responses and cause the ON pathway deficits. This mechanism could explain why myopia increases with activities that maximize accommodative pupil constriction, such as near work, and decreases with activities/treatments that reduce it, such as outdoor activity, atropine, positive defocus, and low contrast,” they stated.

They also emphasized that this is a working hypothesis of the mechanism of myopia development and that it remains “very speculative. Our results are consistent with the hypothesis that accommodative pupil constriction drives myopia progression by reducing retinal illumination. However, future experiments are needed to test this hypothesis directly,” Maharjan and colleagues said.

References

1. Maharjan U, Rahimi-Nasrabadi H, Poudel S, et al. Human accommodative visuomotor function is driven by contrast through ON and OFF pathways and is enhanced in myopia. Cell Rep. 2026; published online February 17. https://www.cell.com/cell-reports/fulltext/S2211-1247(26)00016-1

2. Hartline HK. The response of single optic nerve fibers of the vertebrate eye to illumination of the retina. Am J Physiol Legacy Content. 1938;121:400-15

3. Schiller PH. The ON and OFF channels of the visual system. Trends Neurosci. 1992;15:86-92.

4. Kremkow J, Alonso JM. Thalamocortical circuits and functional architecture. Annu Rev Vis Sci. 2018;4:263-85.

5. Zaghloul KA, Boahen K, Demb JB. Different circuits for ON and OFF retinal ganglion cells cause different contrast sensitivities. J Neurosci. 2003;23:2645-54.

6. Kremkow, J Jin J, Komban SJ, et al. Neuronal nonlinearity explains greater visual spatial resolution for darks than lights. Proc Natl Acad Sci USA. 2014;111:3170-5.

7. Chichilnisky EJ, Kalmar RS. Functional asymmetries in ON and OFF ganglion cells of primate retina. J Neurosci. 2002;22:2737-47.

8. Pons C, Mazade R, Jin J, et al. Neuronal mechanisms underlying differences in spatial resolution between darks and lights in human vision. J Vis. 2017;17:5.

9. Poudel S, Jin J, Rahimi-Nasrabadi H, et al. Contrast sensitivity of ON and OFF human retinal pathways in myopia. J Neurosci. 2024;44:e1487232023.

10. Rahimi-Nasrabadi H, Jin J, Mazade R, et al. Image luminance changes contrast sensitivity in visual cortex. Cell Rep.2021;34:108692.

11. Archer DR, Alitto HJ, Usrey WM. Stimulus contrast affects spatial integration in the lateral geniculate nucleus of macaque monkeys. J Neurosci. 2021;41:6246-56.

12. Mazade R, Jin J, Rahimi-Nasrabadi H, et al. Cortical mechanisms of visual brightness. Cell Rep. 2022;40:111438.

13. Mazade R, Jin J, Pons C, et al. Functional specialization of ON and OFF cortical pathways for global-slow and local-fast vision. Cell Rep. 2019;27:2881-2894.e5.

14. Jansen M, Jin J, Li X, et al. Cortical balance between ON and OFF visual responses is modulated by the spatial properties of the visual stimulus. Cereb Cortex. 2019;29:336-55.

15. Olianezhad F, Jin J, Najafian S, et al. Binocular receptive-field construction in the primary visual cortex. Curr Biol. 2024;34:2474.

16. Williams B, Del Rosario J, Muzzu t, et al. Spatial modulation of dark versus bright stimulus responses in the mouse visual system. Curr Biol. 2021;31:4172-4179.e6

17. Kremkow J, Jin J, Wang Y, et al. Principles underlying sensory map topography in primary visual cortex. Nature. 2016;533:52-7.

18. Kim HM, Joo K, Han J, et al. Clinical and genetic characteristics of Korean congenital stationary night blindness patients. Genes. 2021;12:789.

19. Dryja TP, McGee TL, Berson EL, et al. Night blindness and abnormal cone electroretinogram ON responses in patients with mutations in the GRM6 gene encoding mGluR6. Proc Natl Acad Sci USA. 2005;102:4884-9.

20. Chakraborty R, Park HN, Hanif AM, et al. ON pathway mutations increase susceptibility to form-deprivation myopia. Exp Eye Res. 2015;137:79-83.

21. Hoseini-Yazdi H, Carkeet A, Ahmed R, et al. Relative role of ON/OFF pathways in resolving and adapting to blur in myopes and emmetropes. Invest Ophthalmol Vis Sci. 2025;66:29.

22. Hoseini-Yazdi H, Read SA, Alonso-Caneiro D, et al. Retinal OFF-pathway overstimulation leads to greater accommodation-induced choroidal thinning. Invest Ophthalmol Vis Sci. 2021;62:5.

23. Wagner S. Strasser T. Impact of text contrast polarity on the retinal activity in myopes and emmetropes using modified pattern ERG. Sci. Rep. 2023;13:11101.

24. Kenyon RV, Ciuffreda KJ, Stark L. Binocular eye movements during accommodative vergence. Vision Res.1978;18:545-55.