You've heard about it for years and you've come to accept it as fact, but is it backed by medical science or is a story repeated so often that it's taken on a veneer of truth? We pick apart medical facts from health and wellness urban legends in our segment "Debunk or da Truth." We ask the experts and come up with an answer you can trust. Here are some of the myths we've been busting lately:
The earworm
Do you ever hear a snipit of a song that seems to get stuck in your head for a few days, or even for weeks? Some people refer to this repetitive playing of a (sometimes annoying) song as an earworm. Is there such a thing as an earworm? We asked Dr. Robert Zatorre, professor of neuroscience at the Montreal Neurological Institute and Hospital at McGill University.
The problem starts with something called musical imagery. Musical imagery is usually used to think of a favorite tune. The same parts of the brain are engaged when you imagine a song and when you actually hear that same song. Musical imagery is what makes you able to remember the melody or your favorite song or the latest top 40 hit and, as Dr. Zatorre says, "imagine it and hear it in your mind's ear."
The difference is that when you have a song stuck in your head that same program is running but it's running without much control. It's a form of musical imagery where the imagery has gone off the tracks and is running under it's own steam, according to Dr. Zatorre.
The solution? Try to listen to something else! An even better solution is to play an instrument or actively sing another song out loud. The catch? There's no guarantee this new song won't also get stuck in your head.
Cracking your knuckles
It's a common habit for many of us but have you heard that it can lead to arthritis? Maybe a grandparent or teacher scolded you for that terrible cracking noise. But is it true? We asked a Harvard Medical School professor for the answer. Our expert, Dr. Robert Shmerling is also clinical chief of rheumatology at Beth Israel Deaconess Medical Center.
Believe it or not, there is actually some data on this. Dr. Shmerling is asked often by patients if the practice of cracking knuckles is a healthy thing to do and while there are a few rare reports of dislocated fingers or ligament damage, it seems to be harmless.
Various studies looked at habitual knuckle-crackers compared to those who cannot or do not crack their knuckles. There was not a big difference in terms of the appearance or severity of arthritis.
Dr. Shmerling says one particularly valuable and entertaining report had only one participant, an arthritis doctor. By habit, over the course of his life, the doctor cracked only the knuckles of one hand.
"Well into his advanced years he'd got x-rays of both hands and his hands had equal amount of arthritis on both sides. And he actually wrote this as a letter to one of the major arthritis journals as proof that knuckle cracking does not cause arthritis," Shmerling said.