By Dr Lauren Stewart
Institute of Cognitive Neuroscience
Not being able to sing Happy Birthday might mean you're tone-deaf. But what if you can't actually tell the difference between it and the National Anthem? That's where a condition called amusia comes in - and here's a test to find out if it affects you.
More than one in 10 of us claim to be tone-deaf; but despite the term, most tone-deaf people can hear music perfectly well - they just can't sing.
A different condition, however, does involve a problem in making sense of music. Research has shown that some people, termed "amusic", can neither produce nor perceive music.
It isn't a problem of the ears - they can understand other sounds perfectly well - but when it comes to music, all tunes sound the same (See links below for the test).
While most of us are sensitive to small changes in pitch, amusic people need two notes to be very far apart before they hear them as different. It's no surprise, then, that music, which tends to move in small steps, is literally "lost" on them.
Though most amusia sufferers find listening to music pointless, some even find it annoying and unpleasant.
THOSE WITH AMUSIC...
Can't recognise familiar tunes
Think they sing in tune, but other people tell otherwise
Don't "get" music and rarely choose to listen to it
Anne Vere, an amusic from Newcastle, describes music as an "irritant". When she heard the theme tune to Brief Encounter, voted the UK's favourite piece of classic music for the past five years, she described it as "banging that would be best avoided".
But unless willing to shut themselves off from the many social occasions in which music plays a role, amusics must endure whatever life's jukebox throws at them.
Anne recalls times when she was asked to go to a friend's house to listen to music: "Parties, dinner dances, work dos, I really, really dreaded these occasions."
The behaviour of another amusia sufferer goes beyond passive endurance. She confesses that she puts a CD on the stereo whenever she entertains guests as a way of covering up for her own lack of musical affinity.
Lost in music
For some amusia sufferers, avoiding music is not an option, for the simple reason that singing is part of the job description.
Until he retired, the Reverend Jim Cross was required to sing in parts of his Sunday services. He says of his singing ability: "I am told that sometimes I get the right note, and sometimes I do not, but I cannot tell."
His congregation, however, had no trouble in spotting when Jim went off-key and eventually gave him special dispensation to simply say the lines aloud.
Although anecdotal reports suggest that figures in history such as Che Guevara and American President Ulysses S Grant were afflicted with amusia, the condition has only recently become a topic of scientific interest.
A team headed by Isabelle Peretz at the University of Montreal has pioneered research into the disorder, devising a test which can diagnose whether people are likely to be amusic or not. In the test, two tunes are played which may be identical or may differ at a single point.
If the difference is a change in pitch, people with amusia will not spot it, even if the change is glaringly obvious, causing the tune to go out of key. Comics such as Les Dawson may have built a comedy career out of such musical blunders, but people with amusia just don't hear the joke.
In the general population, there appears to be a great deal of variability in people's capacity to spot differences between tunes. The individual differences in this ability have been shown to be, in large part, genetically determined.
Denis Drayna, from the National Institute of Health in the United States, measured performance of identical twins (who share all their DNA) and non-identical twins (who share only half their DNA) on a test of musical listening.
He showed that the identical twins performed much more similarly on the test, and estimated that between 70% and 80% of the variability in performance can be accounted for by the genes.
The recent surge of interest in amusia has started to de-stigmatise the condition and many sufferers have come forward to participate in the research. While a musical awakening is not on the immediate horizon, the participants take comfort from the finding that they are "not the only ones".
The ability to differentiate is genetic
And as researchers learn more about what amusia sufferers can and can't perceive, there is always the possibility that this knowledge could help sufferers gain access to a musical world.
Just as deaf people learn to enjoy music through its vibrations, people with amusia may be able to choose their listening material according to their residual abilities.
Most amusia sufferers can hear rhythm in music, and most can dance. If the banging of Rachmaninov's piano concerto doesn't make it on to their iPod, perhaps some drum and bass could set their feet tapping.
This seems very similar to how I would describe my colourblind condition. Colours or shades have to be very different before I really notice the difference. I can't see pastels, I need big and bold. Both these conditions affect the senses, so there is probably something similar with smells and tastes too!
Tim Fountain, Beaconsfield
More than half of the world's languages are 'tonal', i.e. where tones contribute as much as consonants and vowels to the meaning of a word (examples include Mandarin, Vietnamese, Norwegian, Igbo, and thousands of others). So an inability to hear tones in such languages would render communication impossible. It would be fascinating to see whether amusic folks could distinguish tone differences in languages that they fail to distinguish in music, thus distinguishing these important cognitive domains.
Daniel Everett, Manchester, England
What a shame Dr Stewart chooses to spoil an otherwise interesting article by referring, in the final paragraph, to the 'banging of Rachmaninov's piano concerto'. Even if she does not herself suffer from amusia, then I fear she is demonstrating her own 'unmusicality' and ignorance of the concert repertoire. Music lovers everywhere know there are several Rachmaninov piano concertos to choose from! Furthermore, if she hears 'banging', then that is the fault of the soloist rather than the music.
Anthony Short, Reading, England
I'd be interested to know if people with amusia speak in a monotone. If not, how are they managing to hear and imitate normal speech intonation? This is much harder to distinguish than musical pitch. Stress in speech, especially for native English speakers is also subtle compared to musical rhythms.
Judith Roads, London UK
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