A research team at Vanderbilt University, Nashville, Tennessee has discovered that knowing precisely where visual signals meet and the brain processes them is vital to treating amblyopia, a vision development disorder in which an eye fails to achieve normal visual acuity.
Alexander Maier, assistant professor of psychology, and Ph.D. student Kacie Dougherty used computerised eye-tracking cameras plus electrodes to record activity of single neurons in a particular area.
“Our data suggest that the two eyes are merged as they arrive in the neocortex and not at a later stage of brain processing, as previously believed,” Mr Maier said. “This major leap in our understanding of how the brain combines information from the two eyes is promising for our search for therapeutic approaches to some of the most common eye diseases in children.”
The current standard treatment is to place a patch over the working eye in an effort to jumpstart the ‘lazy’ one. However, if paediatric eye specialists miss the short window in which to fix the problem, the effects are typically permanent. Therefore, knowing which neurons are involved in the process is significant as it opens the door to targeted brain therapies that reach well beyond eye patches.
“There are six functionally distinct layers in the primary visual cortex,” Dougherty said. “We thought the initial processing happened in the upper layers, but it’s actually in the middle. That’s vital information for developing treatments.”