Visual crowding is a common problem that can make it hard to focus on a single object. (Photo: Ken Teegardin/Flickr)

You may be able to ditch your glasses, new study suggests

Israeli researchers find that some people can train their eyes to cancel out competing objects.

How often does this happen to you? You're trying to look at or read something, but there's just too much visual information competing for your attention. The object of your focus becomes a blur.

You're not alone. It's a common phenomenon called "visual crowding," which makes it hard for people to distinguish or otherwise recognize an individual letter or object when it is surrounded by other objects. Many middle-aged adults who end up needing glasses experience visual crowding, as do people with lazy eye or traumatic brain injuries. At low levels, visual crowding can make it a bit hard to read or drive; at its worst, it can even make it hard to recognize people's faces.

The concept of visual crowding has been studied for decades, but a team of researchers at Tel Aviv University may be close to a solution. In a paper published in February in the journal Scientific Reports, researchers have linked visual crowding to a part of the eye called the fovea, the portion of the retina that is responsible for sharp central vision. Previous research into crowding has looked not at central vision but peripheral vision.

The researchers not only linked the fovea to crowding, they also say it is related to how quickly the brain can process the images that are coming into it through the optic nerve. Professor Uri Polat of the university's Goldschleger Eye Research Institute said in a news release that this research "contributes to a unified model for how the brain integrates visual information."

With this link in mind, Polat and his colleagues worked with 178 study subjects to develop a set of exercises that presented letters on a screen. The letters were displayed progressively faster. Given time, the subjects' vision improved.

"A similar training we conducted two years ago allowed adults to eliminate their use of reading glasses altogether, using a technology provided by the GlassesOff company," Polat said. "Other patients who had lost sharp vision for whatever reason were also able to benefit from the same training and improve their processing speed and visual capabilities." GlassesOff, which launched a smartphone app to improve vision this past December, received $5 million in investment funding this May. The company partially funded the current research, along with a grant by the Israel Science Foundation.

If someone has multiple vision problems, training alone may not address each issue. In a review of the GlassesOff app, one professor of ophthalmology told the Wall Street Journal that exercises could help people to better see objects that would otherwise be blurry but said it would not improve the elasticity of the lens, which remains an important part of overall vision.

This is the latest of several new papers into visual crowding. A study published this past October in the journal Attention, Perception & Psychophysics linked crowding not just to what is going on at a given moment but what happened leading up to it – again, a question of the brain's ability to process information in a timely manner. Another study, published in the current issue of NeuroImage, linked crowding to the patterns in which objects appear and found that objects of similar heights created more crowding. Yet another study published in May in the Journal of Neurophysiology linked crowding to impairment of the middle temporal visual area of the visual cortex in the brain.

While there is still much research to be done on visual crowding, the techniques in the Tel Aviv University study show promise. According to the researchers, one subject had trouble reading before he started the study. He has since earned his master's degree.


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You may be able to ditch your glasses, new study suggests
Tel Aviv University researchers may have found a solution to a common problem known as "visual crowding."