Briefs (11/16/06)

Researchers study the brain process behind shifty eyes

Mallory Womer

Staff Writer

If… Researchers study the brain process behind shifty eyes

Mallory Womer

Staff Writer

If our eyes are constantly moving, why does everything that we see appear to be so clear?

Marc Sommer, assistant professor of neuroscience at Pitt, and Robert Wurtz, senior investigator at the National Eye Institute, proposed an answer to this question in a paper that was published online by Nature today.

The two scholars researched the different pathways that vision takes to multiple centers of the brain. In work previously published by the pair, they suggested that one pathway could cause the process needed to keep our vision clear. Just before our eyes make a saccade, or little jump, the visual neurons of the brain may actually shift their receptive fields, thus accounting for the movement that is about to occur in the eyes.

In today’s edition of Nature, Sommer and Wurtz share evidence they have collected that supports this theory. The study was conducted in Wurtz’s laboratory at the National Institute of Health. Monkeys served as the test subjects.

“The impact [of these findings] is understanding the basic circuitry of the brain related to this particular problem of the brain still focusing while our eyes are moving around,” Wurtz said. “The brain compensates for the fact that our eyes are moving all the time.”

Wurtz, who has spent nearly his whole career working with the NIH, emphasized the importance of the duo’s methods for studying the brain. He said that normally, visual perception is studied with the retina stabilized and the eyes not moving. For this study, which really focused on how the brain functions, the eyes were allowed to move around, giving more reliable results relating to visual perception.