Scientists have known for a long time that people with early-onset blindness have more accurate hearing abilities. However, there is no definitive answer as to why.
“There is a lot of speculation that blind people are very good at auditory tasks, because they have to find their way into the world without visual information,” says neuroscientist Ione Fine from the University of Washington.
Visually impaired people often have much better hearing ability than normal people.
To find the answer, Fine and her team used functional magnetic resonance imaging (fMRI) to examine activity in the auditory cortex, the part of the brain that processes auditory information, in both the blind and the group. visually impaired.
Of the study participants, 4 had early blindness and 5 had non-developmental eyes.
In the trial, participants were exposed to a number of sounds resonating at different frequencies, an fMRI device that would record their brain activity.
When the researchers analyzed the results, they discovered that the blind people in the experiment tended to process sound in a narrower, more precise “bandwidth” than the normal people, indicating a greater sense of sensitivity. Their frequency-correcting sense in the auditory cortex is finer-tuned than in non-blind people.
For a person with myopia, it is not important to accurately represent sounds because they can see to help them recognize objects, while blind people only have auditory information.
This shows us changes in the brain that explain why blind people are better at picking out and identifying sounds in the environment.
Now researchers are continuing to understand this particular mechanism better.