A new study from The University of Western Australia has found computer screens, as opposed to mobile phones or tablets, are contributing to the myopia epidemic.
Senior research fellow Dr Samantha Sze-Yee Lee from the Lions Eye Institute (LEI) used data from the Raine Study, a Perth-based multigenerational observational study, collected from 600 young adults to discern the types of digital screens that contributed to the development of myopia.
Lee found that short-sightedness progressed faster in those who reported six or more hours per day of computer usage relative to those with low computer use while time spent on mobile phones did not have any effect.
“The reason for this difference may be due to a phenomenon called ‘peripheral defocus’,” Lee said.
“When you look at your mobile phone, everywhere in our peripheral vision, with the exception of the small phone screen, is further away and relatively blurred. The brain registers things that are generally far away and there is no need for the eye to become more short-sighted.”
She said when people focus on a large screen such as a desktop computer, more of their peripheral vision is taken by the screen.
“The brain sees that more short-distance work is involved, triggering the eyes to become more short-sighted,” she said.
Myopia is associated with increased risk of future eye problems, such as glaucoma and retinal degeneration, so understanding the effect of the modern world on eye health is important, the researchers noted.
“In this day and age, it is almost impossible to avoid digital screens,” Lee said. “Mobile phones can easily be used outdoors, as opposed to laptop and desktop computers, and spending more time outdoors is known to be protective against myopia.
“It is hoped the findings will help scientists develop techniques to mitigate the detrimental impact of computer screens on eyesight.”