Do you have a buddy who just can’t sing? You know the kind: they can’t even do “Happy Birthday” properly. Does your friend really lack all talent? Well, hang on. Maybe he has something called “congenital amusia.” This is a perceptual disorder that prevents people from hearing changes in notes. Their brain just can’t process music in the correct way and as a result when they try to sing, things come out all wrong. This is also what we call “tone deafness.” Melanie Provost, a researcher at the International Laboratory for Brain, Music and Sound in Montreal disputes the common figure that 4% of the population is tone deaf. She thinks it’s much higher than that. To take a tone deafness test, go to www.brams.org/tests. If you score anything less than 70%, you should probably keep the singing to yourself.