SSS 2010-10-11（在线收听）

This is Scientific American’s 60-Second Science. I’m Christie Nicholson. Got a minute?

Is it an old wives tale or can deaf people actually see better? Scientists have long thought that the structure of our brain is fixed. For instance, from birth the auditory cortex will receive only sound or the visual cortex will receive only visual input.

But in the last decade neuroscientists have overthrown this idea in favor of a more malleable brain. 

New research published this week in the journal Nature Neuroscience supports that view. It helps explain why those who are congenitally deaf may have extraordinary sight.

Since the auditory cortex sits there, at birth, waiting for auditory inputs that never come, it actually starts receiving visual stimuli instead—in cats anyway. And the neural real estate devoted to vision increases.

Researchers compared congenitally deaf cats to hearing cats, and found that deaf cats have enhanced peripheral vision and motion detection.

And they confirmed that the part of the auditory cortex that picks up peripheral sound switches to peripheral vision.  

With the deaf it’s especially good to have increased peripheral vision. If you cannot hear a car approaching from the side, it'd be advantageous to actually see it.

Thanks for the minute. For Scientific American’s 60-Second Science, I’m Christie Nicholson.