Universal eye problem could lead to better vision

Dutch researchers have presented evidence that crowding, the phenomenon in which an object in the peripheral visual field is more difficult to recognize when surrounded by other objects, actually leads to better vision.

Using simulations, the researchers demonstrated that several fundamental properties of the crowding effect can be explained as the byproducts of a mechanism that may have a function in contour integration.1 These results help differentiate between earlier theories about both the neural and functional origins of crowding, the authors said.

“Our eyes are continually being bombarded with information, and our brains have to decide what is important. Simulations conducted with our model show that crowding appears to help make the important information much clearer,” Frans Cornelissen, MD, an author of the study, said in a University of Groningen, Netherlands, news release. “If you look at pictures without crowding, the illustration always stays a bit fuzzy. However, if you then apply crowding, the edges of letters and objects in an image become much sharper.”

Dr. Cornelissen, a neuroscientist in the Laboratory for Experimental Ophthalmology at the University of Groningen, said crowding is an image-strengthening trick used by the brain to differentiate between important and useless information. The model used in the study, published in the journal Public Library of Science Computational Biology, provides a fundamental sense for a better understanding of our brain functions, Dr.Cornelissen said, and he envisions a number of potential practical applications, such as in dyslexia.

“Previous research has shown that people with dyslexia have more problems with crowding. Our model can simulate how someone with normal sight identifies a text and how that differs from someone with more problems with crowding,” Dr. Cornelissen said in the news release.

1. van den Berg R, Roerdink J, Cornelissen F. A neurophysiologically plausible population code model for feature integration explains visual crowding. PLoS Comput Biol. 2010;6(1): e1000646.

28-04-2010