The short version
- People blind from early in life were better than sighted people at telling two close pitches apart, but no better at a basic tone-detection test.
- A computer model said the gain came from less random variability in the brain’s response, not from sharper tuning in the ear.
- More musical training predicted the same drop in that internal noise, which suggests experience rather than blindness itself drives it.
Do blind people hear better? The research has been contradictory, and a new paper in the Journal of Neuroscience suggests why. Woon Ju Park of the Georgia Institute of Technology, with Jasmine Awad and Ione Fine, gave early-blind and sighted people with matched musical training two tests. One, detecting a tone in notched noise, measures how finely the ear and brainstem separate frequencies. The other asks a listener to say which of two close pitches is higher, a job done in the cortex. The groups were equal on the first. The blind group was better on the second.
A computational model found the best explanation was lower “internal noise”: less random wobble in the brain’s response to the same pitch from one trial to the next, rather than narrower frequency tuning. Musical training predicted the same reduction. That is a different account from Fine’s own 2019 brain-imaging work, which had reported narrower tuning in the auditory cortex of blind people.
“Enhanced hearing in individuals who became blind early in life is selective,” Park said. None of the sources we could open gives the number of participants or the size of the difference, and the paper itself was not accessible to us.
