Written on Thursday, September 28, 2006 by Gemini
If you always thought there was something wrong with your tone-deaf friends, research has now backed you up: they seem to be lacking some brain material. Scientists in Montreal, Canada, and Newcastle in the United Kingdom have identified the part of the brain that causes some people to sing like larks — and others to make you run for your earplugs as soon as they pick up the karaoke microphone. Krista Hyde at the Montreal Neurological Institute and her colleagues used magnetic resonance imaging (MRI) to study the brains of tone deaf, or a music, people and compared the images with others from people with normal musical ability.
The studies from both countries used identical methods and each set of results highlighted an area in the front of the brain — the right inferior frontal gyrus — which contains less white matter in a music people than in the musically normal. White matter is responsible for information transmission in the brain, and the deficiency seen by Hyde probably hampers communication in the brain’s right hemisphere, the researchers suggest, making music comprehension difficult.
Musical ‘behaviour’ is often quantified by standard tests for six different abilities, including a sense of metre, the ability to remember a tune, and the ability to decipher changes in key, pitch, pitch direction and rhythm. The amount of white matter in the brain matches up with the tests for melody, rather than rhythm, the research in Brain reveals. This is consistent with previous work showing that tone deafness is largely a pitchbased condition.
The new work shows a crucial link between musical behaviour and anatomy, which could prove a real breakthrough in understanding the condition, says Hyde.
Early-to-bed gene found
Scientists are closer to understanding how a particular gene mutation causes some people to be extreme morning larks—findings that could aid in understanding various sleep disorders. Several years ago, researchers linked a gene known as Per2 to an inherited disorder called familial advanced sleepphase syndrome. The disorder causes people to follow an unusual sleep pattern: they’re typically ready for bed by 7 pm, and ready to start their day hours before sunrise.
Scientists have known that FASPS is essentially a glitch in the body “clock,” or circadian rhythm, and that the problem stems from a mutation in Per2—one of a handful of proteins that has been shown to help govern the body’s roughly 24-hour clock. But the new study shows more precisely what goes wrong in the body clock’s timing.