X-ray vision? Not quite, but the deaf do have super sight

Bill Briggs writes: The news release from the science lab contained one eye-popping word: “Research discovers how the deaf have super vision.” “Super?” Seriously? When we think of super sight, we flash on a caped man flying with an “S” on his chest, peering into hideouts with X-ray vision. Can Marlee Matlin see through walls? No. But she does probably see more acutely than those who can hear. New research suggests that many congenitally deaf people possess two types of extraordinary sight: Expanded peripheral vision and the ability to detect motion imperceptible to the hearing. For example, when people with normal hearing stand at a clock’s center and stare at the 12, they probably can see the 10 and 2. But those with congenital deafness typically can also detect the 9 and 3, says Stephen Lomber, an associate professor and researcher with the Centre for Brain and Mind at the University of Western Ontario. Also, deaf people recognize when an object that appears stationary to those with hearing is actually moving very slowly. “These are abilities that most of us as humans – or most animals – don’t have,” he adds. Until now, scientists have been unable to explain how this happens. But according to research published today in Nature Neuroscience, Lomber and his team found that people who are born deaf or who lose their hearing early in life tap a brain area called the auditory cortex. That swath of gray matter, meant to process sound, is rewired to boost sight. They figured this out by testing cats – some born deaf, some with full hearing and then confirmed the results through interviews with deaf people. The scientists used banks of LED screens to gauge and compare the cats’ peripheral vision and motion detection. The team checked its findings by chilling and shutting off the deaf cats’ auditory cortexes. All the amplified vision normally exhibited by the deaf cats suddenly vanished. “They lost the super part,” Lomber said. The brain’s ability to remake itself may mean that congenitally deaf people also have keener senses of touch and smell, Lomber theorized. “The brain is a pretty efficient structure,” he said. “It’s not going to let processing capacity go to waste. If it’s not going to use it on sound, it’s going to use it on something else.” Are any of your senses especially keen? Tell us about it in the comments.Find The Body Odd on Twitter and on Facebook.