Re: What causes tone deafness?

Hi,

This is an interesting question. Sometimes I wonder if I am tone deaf; although i enjoy music I can't seem to be able to tell when my piano is in tune or out of tune.

There's a wonderful internet resource at the National Center for Biotechnology Information (NCBI) called Online Mendelian Inheritance in Man (OMIM). OMIM is an encyclopedia of information about inherited traits in humans.

See the OMIM entry on tune deafness. There is also a related entry on perfect pitch.

Perfect pitch appears to be associated with activity in a region of the brain called the posterior superior temporal region, which also contains the area of language comprehension. Both perfect pitch and the opposite, tune deafness (also known as amusia or dysmelodia), seem to be inherited as irregular dominants. Both traits are probably multifactorial with many genetic and environmental causes. I wasn't able to find anything about brain or ear anatomical differences in tune deaf or perfect pitch individuals.

Here's a reference on a case study of a tune deaf woman with no other medical or social problems. She just has no talent for music and takes no pleasure in it.

Peretz, I.; Ayotte, J.; Zatorre, R. J.; Mehler, J.; Ahad, P.; Penhune, V. B.; Jutras, B. Congenital amusia: a disorder of fine-grained pitch discrimination. Neuron 33: 185-191, 2002. Here's a link to the Pubmed abstract of the above article.

Another scientific article on this subject.

Here's a related story for a more general audience.

Sorry I didn't quite address your question of mechanism but hope this helps and is of interest anyway.

Sanjida