Amblyopia "Drives" Information from the "Good" Eye

"Most often in amblyopia patients, one eye is better at focusing," says Bas Rokers, a University of Wisconsin-Madison psychology professor. "The brain prefers the information from that eye, and pushes down the signal coming from the other, 'lazy' eye. In a way, it's better to think of the better eye as a bully, rather than the poorer eye as lazy." That's the story from a University of Wisconsin press release. As the brain develops its preference for the dominant eye's input, it alters its connections to the weaker eye, according to a study Rokers and colleagues published this week in a special edition of the journal Vision Research. "If you continually have that bullying happening, that changes the signals coming from the lazy eye," Rokers says. "We wondered, if you don't have as many signals traveling back and forth, does that come with a physical change in those passageways?" Using a brain scanning method called diffusion-weighted imaging, the researchers mapped three sets of pathways known to carry visual information from the eyes to the brain. In people with amblyopia, the researchers saw water diffusing more easily down the brain's visual pathways. Read more.