A rock song says music can soothe the soul but hospitals are finding it can help premature infants and other sick babies, too.

Music therapy played live is increasingly being used in newborn intensive care units around the country.

Research suggests it may slow stressed infants’ heartbeats, calm their breathing, and improve sucking and sleeping. Some studies suggest it might even help them go home sooner. It can also help them bond with parents even before the tiny babies are able to be held.

Elizabeth Klinger is a music therapist at Chicago’s Ann & Robert H. Lurie Children’s Hospital. She softly sings and plays guitar, and says that the live performance does much more than entertain babies.