Tuesday, December 30, 2008

My Cell Phone Rings in A Minor

How do people with absolute pitch glance at black-and-white squiggles on sheet music and hear the melody in their heads?
by Alissa Poh
from scicom.ucsc.edu/SciNotes

Summary

Musician Alissa Poh is a research scientist turned science journalist. She says she would rather be a storyteller of science rather than its slave.

The author has perfect pitch or absolute pitch (AP). She hears the everyday sounds around her in musical terms. Her cell phone rings in A minor. Her car horn is somewhere between an E and an F and her refrigerator hums in B flat. As long as she can remember she has been able to recognize and name the pitch of any note.

Oliver Sacks, the noted neurologist and author of Musicophilia, writes that to those of us who don't possess AP, it seems like an uncanny other sense but to those with are born with it, it seems perfectly normal.

Researchers are looking at the genetic hereditary basis of absolute pitch and how that combines with hereditary influences. Researcher Joseph Profita published a paper in 1988 in which he shows that the AP ability clusters strongly within families.

Poh spent time with absolute pitch genetic researchers Jane Gitschier and Beth Theusch from the University of California in San Francisco. Gitschier and Theusch were joined in the study by Iranian grad student Siamak Baharloo whose was interested in also examining the role of musical training on AP development.

First a survey was sent to 900 musician. Then an online test was devised where participants had to distinguish pure fundamental frequency pitches and piano tone pitches, each within three seconds. All survey and test participants had to have received formal music lessons. The results of the testing helped to produce a "relative risk estimate", the prediction that sibling were 10 times more "at risk" for AP than individuals within the general population. Children of a parent with AP were found to have a 50/50 chance of having it.

The researchers compiled data and collected DNA samples in search of genetic evidence of AP. The compilation of information continues with the team eventually hoping to find the one genetic variant linked to AP.

So far, the ACSF researchers have noted that as people get older their pitch perception tends to shift towards the sharper or higher side. Their hypothesis is that just as our eyes change with time, so do our ears. They also noted that most people with AP tend to slip up in their pitch indentification around G sharp and A. This is likely because A is the usual pitch used for tuning. A is often tuned at 440 Hertz, but depending on the type of music and geographic location, the tuning pitch can vary.

Research into AP is shedding light on the question of neuroplasticity (how the brain changes with experience) and on how long-term memory works.

Some scientists are skeptical about the genetic correlation of AP. One of these is musician turned neuroscientist Daniel Levitin. Levitin feels that without an evolutionary advantage to AP, it is unlikely to be inherited genetically. Likewise, he doesn't think the AP researchers will be able to separate "nuture from nature".

Reflections

Alissa Poh's story traces the development of the various stages of the study, which I found captivating. Rather than just listing the findings of the study, it is interesting to follow the various steps involved in the evolution of the project.

It is intriguing that many of the scientists involved in this research have a musical background.

It seems very appropriate that this article is written from the perspective of someone who does possess AP. It must be a tremendous advantage as a musician to possess absolute pitch, with the exception that musicians who regularly perform early music frequently must have to get very good at mentally transposing!

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