Music therapy is fairly new to the treatment scene. It started after musicians played for hospitalized World War I and World War II veterans, and it's now an established form of therapy beneficial to our emotional, cognitive and physical health.
Music therapists are educated in music and sound theory, in addition to psychology and medicine, and use techniques such as singing, listening to music and creating music. These various techniques are forms of rehabilitation and stress and anxiety relief, and they open the door to verbal communication.
Evidence suggests intentional therapeutic music — not just listening to songs on your iPad, although that also can have relaxation benefits — is associated with physiological changes. For example, it boosts an antibody called immunoglobin A, which has a role in the body's fight against infection. It also appears effective for babies cared for in neonatal intensive care units (NICUs). These tiny patients respond to live music with higher reported heart and respiratory rates, and they experience better feeding and weight gain than those without the therapeutic benefit of music.
Studies have also found that patients who were treated with music therapy rather than with anxiety medication prior to surgery were overall less anxious than those who'd only been given drugs. And in the same vein, music that falls within 60 to 70 beats per minute (about how fast most hearts beat) elicits the body's relaxation response (the opposite of the body's flight-or-fight response).