You probably know someone who is tone deaf, or perhaps you are tone deaf yourself. The official term for people who have difficulty recognizing the difference between tones is amusia. NPR’s All Things Considered had a report a couple days ago on research into “musical disabilities”. It focuses on a woman named Monica who may have congenital amusia, as she has no physical defects or damage that would cause her to be tone deaf. Monica can not distinguish the differences between changes in tone unless they are significantly different. There are sample recordings on the page so you can give this a try yourself. Researcher Isabelle Peretz’s work in creating tests like these for detecting amusia will help geneticists track down the genes that cause this trait. Some people who can’t sing just can’t sing, but some people can’t truly hear what they are trying to duplicate with their voices. (thanks Renee!)