Tuning a piano also tunes the brain, say researchers. Listening to two notes played simultaneously to get them pitch perfect seems to cause the brain to adapt.
Brain scans revealed highly specific changes in the hippocampus, which governs memory and navigation. These correlated with the number of years that tuners had been doing this job.
For the study, the Wellcome Trust researchers at University College London and Newcastle University used magnetic resonance imaging to compare the brains of 19 professional piano tuners and 19 other people.
"We already know that musical training can correlate with structural changes, but our group of professionals offered a rare opportunity to examine the ability of the brain to adapt over time to a very specialised form of listening," the BBC quoted Sundeep Teki as saying.
Other researchers have noted similar changes in taxi drivers as they build up detailed information needed to find their way around London's labyrinth of streets.
"There has been little work on the role of the hippocampus in auditory analysis," Prof Tim Griffiths, lead researcher of the new study, said.
"Our study is consistent with a form of navigation in pitch space as opposed to the more accepted role in spatial navigation," he added.
The study has been published in Neuroscience.