Musical training can improve your hearing, according to several studies presented in Chicago at Neuroscience 2009, the annual meeting of the Society for Neuroscience.
The studies found that serious musicians are better than other people at perceiving and remembering sounds. But it’s not because they have better ears.
Sounds come in through the ears. But they travel through the nervous system and get interpreted by the brain.
That means your hearing can change even if your ears don’t, says Nina Kraus, who directs the Auditory Neuroscience Laboratory at Northwestern University.
“Your hearing system becomes tuned by the experiences that you have had with sound throughout your life,” Kraus says.

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Say What?! Musicians Hear Better : NPR