Those earphones the dentist offers when you plop in the chair aren't just for entertainment or blocking out the sound of the drill -- they're an adjunct to delivering pain relief in the form of music.
Scientists have been documenting the connection among music and pain relief, stress reduction and eased anxiety for decades, but new appreciation for brain structure and chemistry have helped boost understanding.
One study done last year found that when we listen to music we like, the brain releases the signaling molecule dopamine to bring on pleasurable sensations.
It's the same reward pathway activated by food, sex and drugs.
In another study published last month by researchers at the University of Utah, most of 143 people involved were able to mitigate the pain from a shock applied to a fingertip by following a song and listening for unusual tones.
David Bradshaw, lead author of the study published in the Journal of Pain, said the type of music didn't seem to matter so much as how well it held the patient's interest. People who were most anxious seemed to benefit the most.
There is also substantial evidence that patients who require mechanical ventilation to breathe can benefit from listening to music.
Researchers reviewed data from eight trials involving 213 patients who all required mechanical breathing support through the mouth, nose or throat (tracheotomy). Seven of the experiments used recorded music; the last had a therapist play live music in a tempo matched to the patient's respiratory rate.
The review was carried out by Joke Bradt, a researcher of creative arts therapies at Drexel University in Philadelphia.
In all cases, those listening to music had reduced anxiety and reduced heart and breathing rates -- although not blood pressure -- compared with control groups that received standard care without music.
A number of other studies in recent years have found that listening to music, particularly slower, mellower tunes, can positively affect blood pressure, heart rate and even heart function.
Most of the studies and the measured effects have been modest. The impact has been a 3- to 6 point reduction in beating heart (top number) blood pressure, which translates into reducing the risk of heart attack and stroke by 5 percent to 15 percent.
But a patient singing meaningful songs can have an even more powerful effect, a case study reported last spring in the journal Arthritis Care and Research showed.
The patient was a 76-year-old woman in the Dominican Republic with severe arthritis pain in her knees. She was accepted for total knee replacement through a charitable program that brought surgeons from the U.S.
But when she arrived at the hospital for surgery, her blood pressure was too high to safely proceed with surgery. With a limited window for the operation, more medicine likely wouldn't reduce it quickly enough, if at all.
The woman told her doctors that she often sang hymns to calm herself and help her sleep. They encouraged her to sing in her hospital room, and checked her blood pressure as she did. After two songs, her pressure was down 60 and 30 points. The doctors told her to keep singing as she wished during the night, and the next morning, blood pressure still in check, she was cleared for surgery.
Her experience "expands on medical evidence by showing that producing music or singing (along with listening to music) also has potential therapeutic effects in the preoperative setting," said Nina Niu, a Harvard Medical School researcher who was on the woman's medical team and was lead author of the online report on the case.
While a lot more study needs to be done before singing can be considered standard for pre-op in hypertensive people, Niu noted, "Singing is simple, safe and free. Patients should be encouraged to sing if they wish."
(Contact Lee Bowman at bowmanl(at)shns.com.)
THE MEDICAL JOURNAL