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? Alissa Poh delves into the science behind this ‘extra sense.’ Illustrated by Filipe Franco.
Illustration: Filipe Franco
This morning, I honked my car horn indignantly at a passing motorist who had nearly taken off my side mirror. That tone is somewhere between an E and an F, my brain registered immediately. I can also tell you that the intercom system of a shopping mall I frequented as a child buzzes in D major, and my cell phone rings in A minor.
Car horns, train whistles, and the like are real music tones to me, not mere noise. I have absolute pitch, also called perfect pitch, which lets me instantly recognize and name the pitch of any note, without needing thought or external reference. I have no idea how or even if I acquired this ability; it seems like it’s always been there, ever since I was introduced to the 12 semitones of a chromatic scale.
Prominent neurologist and author Oliver Sacks writes in his book Musicophilia: “For most of us, such an ability to recognize an exact pitch seems uncanny, almost like another sense, a sense we can never hope to possess, such as infrared or X-ray vision; but for those who are born with absolute pitch, it seems perfectly normal.”
Still, people with absolute pitch didn’t just get it randomly. There is science at work here, and researchers are finally giving this subject the scrutiny it deserves. Geneticists are trying to determine the hereditary basis for absolute pitch, where that intersects with environmental influences, and how this might help us understand the way our brain structure changes with different experiences—a phenomenon called neuroplasticity.
This growing field of research and its tantalizing possibilities piqued my curiosity. Maybe there’s really more to say about what I have than vague descriptions like “a musical ear.” While I’ve always known I was different, musically speaking, it’s one thing to dwell in a world foreign to most people, and another to understand how and why I got there.
Talent genes
It’s a gray, rainy Thursday afternoon when I first visit the medical center on the Parnassus campus of UC San Francisco. There, I meet Beth Theusch, graduate student of geneticist Jane Gitschier. Theusch ushers me into her advisor’s office. It has a cozy feel; Gitschier uses lamps rather than overhead lighting, casting the photographs of her daughter Annie in a warm glow.
Gitschier, an investigator with the Howard Hughes Medical Institute, is small, but she makes up for that in energetic cheerfulness. Earlier in her career, she focused on what most human geneticists do: figuring out the genetics behind various human diseases. However, she has spent the last 10 years traversing a different path, in search of the genetic explanation for absolute pitch, which scientists shorten to AP.
“Obviously, AP is not a human disease,” Gitschier remarks. “But I had, and still have, a very strong sense that it’s genetic, or I wouldn’t have bothered to work on this project.” She believes investigating genes that confer talent rather than cause suffering is an equally important research area.
There’s also a personal reason. “I trained as a singer,” Gitschier says, “and I worked with pianists who had AP. It just struck me that this had to be genetic, if only because it seemed so uncanny.” Singing was always a hobby, she notes; only when she was a graduate student were voice lessons possible. “I seriously considered making a career out of it,” she says, before adding with a laugh, “but it turns out being a scientist is a more stable financial path.”
Today’s musicians may not dwell on it, but scientists floated the notion that AP could be hereditary as far back as 1883, in a German publication by C. Stumpf. Those suspicions were born out in a 1988 paper in the American Journal of Medical Genetics, showing that AP ability clusters strongly within families. The paper’s lead author, the late Joseph Profita, was both a renowned psychiatrist and Juilliard-trained musician who also had AP. His work generated keen interest, especially among scientists with musical backgrounds.
“Lots of people have early music training, but they don’t go on to develop AP,” Gitschier notes. “So there must be another ingredient, another component.” And from her conversations with musicians and others, Gitschier doubts that life experience is the only factor. People with AP tell her, “This is something I’ve had my whole life; I didn’t work at it, and I thought everybody had it.” So it’s likely, Gitschier believes, that there’s something inherent here.
Designing an AP test
Gitschier planned to collaborate with a colleague, psychiatrist Nelson Freimer (currently at UCLA), in tackling AP from a geneticist’s viewpoint. Then in 1995, along came Siamak Baharloo, an Iranian graduate student interested in both genetics and neurobiology. He decided to jump on the bandwagon, with Gitschier and Freimer as co-advisors, and examine the role of musical training on AP development.
“He was fearless,” Gitschier chuckles. “He started out by simply going right to the San Francisco Conservatory of Music and interviewing people.” And Baharloo didn’t stop there. In total, he distributed 900 surveys to places ranging from the local UCSF Symphony and Michigan’s Interlochen Center for the Arts, to Milan’s La Scala Opera House. Musicians and artists from these places completed 612 of the surveys. Baharloo then worked with Paul Johnston, a post-doctoral fellow at UCSF, and designed an auditory test to assess AP in those claiming to have this trait.
In Baharloo’s two-part test, participants had to identify 40 pure tones and 40 piano tones, each within three seconds. A tone from any instrument produces sound waves with both a fundamental frequency and overtone frequencies. If you strike the note A on the piano, it generates sound waves at a fundamental frequency of 440 Hertz, as well as at 880 Hertz (the octave above it) and even higher frequencies, all of which are overtones. A pure tone is a note’s fundamental frequency with no overtones; it’s computer-generated and not a natural sound.
“Siamak was curious as to whether people were recognizing tones by the fundamental frequency, or whether they were using overtone information,” Gitschier says. “Some pianists might know their instrument really well and be able to make pretty quick guesses on the piano tones, but they didn’t meet our criteria unless they also scored well on the pure-tone test.”
By "criteria," Gitschier means AP-1, the study’s most rigorous definition of clear-cut absolute pitch, based only on pure-tone test performance. From this initial survey and acoustical test, Baharloo came up with a relative risk estimate. That’s not an ominous measure; rather, it simply predicts the chances that a sibling of an AP-possessing person also has this trait. He found that such siblings were approximately 10 times more "at risk" for AP than individuals in the general population who also had early musical training.
All study participants, with or without AP, had received formal music lessons. They weren’t “just horsing around on a piano at home,” Gitschier says. This enabled the researchers to measure the influence of genetics, since early musical training may be intertwined with AP development. In fact, the study noted that more than half of those with AP began music lessons between the ages of four and six. Baharloo speculated that this could mean a stronger “wiring” of pitch perception in their neural circuitry. Alternatively, Gitschier says, some people with AP tell her they were drawn to music and sound early in life, and simply craved lessons.
This isn’t the whole answer, since early exposure to music doesn’t guarantee AP. Gitschier hypothesizes that parents can pass the AP gene(s) to their children, with each child having a 50/50 chance of inheriting this genetic predisposition. AP as a trait will then arise in children having both this inheritance and early music training to solidify the necessary brain patterns. It makes sense, personally—AP has been part of me since I started music lessons at age four.
Today, the gene hunt continues. Gitschier and Theusch have now refined Baharloo’s original auditory test. They’re using their online UC Genetics of Absolute Pitch Study to recruit siblings with AP and collect DNA samples from their families. Theusch is looking at “markers” in these samples to identify areas of the human genome shared among relatives with this trait. She’s hoping to pinpoint a specific region, or regions, in the genome most likely involved in AP. Finding the answer, though, will require many more AP families than she now has. Then, she'll comb through the region(s) for candidate AP genes. Finally, Theusch will compare candidate genes between individuals with or without AP, looking for DNA sequence variations that appear more frequently in people with AP. Eventually, she hopes to find at least one genetic variant linked to AP.
Click here to take the test!
"Do you have absolute pitch?" the computerized questionnaire asks me. There are three choices: Yes, No, I don’t know.
What if I actually don’t? I worry, even as I click "Yes" and proceed with the test. The three-second intervals for each tone whiz by. I learn that instant mental identification of tones is one thing; using the laptop mousepad to click rapidly on the one-octave keyboard displayed is quite another. Ten minutes later, the computer informs me that I’ve received an AP-1 score.
My score is added to the “AP clump” seen in a plot of results from all participants. The other distinct group comprises those who made random guesses and got several tones right by sheer chance, thus earning a score. Such a striking two-group distribution suggests AP may not be the product of many different genetic factors, where each only plays a small role. There could well be a single gene responsible, or a handful at most, Gitschier says.
The team made two other curious observations in the study’s preliminary results, published in the September 11, 2007 issue of the Proceedings of the National Academy of Sciences.
The first is that as people get older, their pitch perception shifts. “People would tell me, ‘I used to have AP as a kid, but it’s going off as I get older,’” Gitschier says. “We heard such anecdotes all the time. Now we look at all the note-naming data coming through the Web, and clearly people are hearing things sharper as they get older.” For example, they tend to label C as C-sharp. At age 80, Theusch says, they often think it’s D rather than C.
Gitschier’s hypothesis is that some mechanical property in our ears changes with time. For instance, a key membrane in the cochlea could become less flexible, thus relaying a different frequency to our auditory nerves. Pitch mislabeling could occur if the neuron that originally fired in response to the frequency for F now fires when E is sounded.
It’s interesting, Gitschier says, that those with AP may provide a unique window into such hearing changes. “Think about vision—as our lenses harden with age, we’re probably perceiving colors a little differently, but you wouldn’t realize it unless you get cataract surgery,” she reflects. “So we’re probably all hearing things sharper as we get older, but you wouldn’t know that unless you have AP.”
The second observation, while related to sharpened pitch perception, appears to occur more generally, not just in older study participants. Most people with AP slip up on the note G-sharp and mistake it for A, which is a semitone higher.
Gitschier has a theory about why this happens, too. If there’s a single note musicians are familiar with, it’s A—the universal tuning pitch. However, A can be tuned to different frequencies; it’s typically 440 Hertz in the U.S., while the Berlin Philharmonic ups it to 446 Hertz. Orchestras specializing in early music have A tuned to a frequency as low as 415 Hertz. That’s where G-sharp usually is. So those with AP may have learned to adapt to A and its wide range of frequencies, Gitschier says.
Brain clues
Dennis Drayna, a geneticist at the National Institute on Deafness and Other Communication Disorders in Bethesda, Maryland, describes people with AP as having “a special group of ears.” He’s thrilled this subject is finally receiving serious scientific attention.
“It was in the land of anecdote forever, until quite recently,” Drayna says. “In the U.S., not much research has been done on the genetics of AP, because it’s not a disease. Europeans, in my opinion, are a little more broad-minded about this. They view AP as important in better understanding the auditory system and the brain in general.”
Drayna is intrigued by the two-group distribution of AP observed by the UCSF researchers. Some view this as evidence that AP is a Mendelian trait, controlled by a single locus or fixed position on the chromosome, with a simple pattern of inheritance that readily separates affected and unaffected individuals.
“I don’t think it’s purely Mendelian,” Drayna counters, “or we would see much bigger families with many more people affected, the way hemophilia runs through Europe’s royal families.” It’s not clear there is strong evidence either for or against this straightforward inheritance pattern, he adds—“it’s more like we don’t know.” But he thinks the UCSF team, by analyzing AP’s occurrence in as many families as possible and comparing its pattern to what would be expected for a purely genetic trait, is on the right track toward figuring out the genetic basis for AP.
Studying AP may shed light on general questions about neuroplasticity—how our brains change with experience. “There has to be something in the brain that allows people with AP to have long-term pitch memory,” Gitschier says. “But what is it that shuts off early in those who don’t have AP, or fails to shut off in those who do? And what causes this difference?”
Drayna also thinks AP studies may provide a key to understanding how long-term memory works. The biology of memory, he says, is still poorly understood—we haven’t figured out how the brain stores different kinds of information over time. “You can always distinguish pink from red, and you don’t need someone to show you red before you decide something else is pink,” Drayna says. “We have a type of visual memory that our auditory system apparently doesn’t, but people with AP do.”
Specifically, Drayna believes that AP—as an “add-on” in the brain rather than something gone awry—provides a unique window into this remarkable organ, especially with the advent of functional magnetic resonance imaging (fMRI). This allows researchers to visualize and map regions of the brain used in everyday tasks, like reading and calculation. So far, fMRI studies show that the frontal lobes contain certain necessary mechanisms for pitch-labeling. As well, imaging studies by neurologist Gottfried Schlaug of Harvard University have revealed that the planum temporale—located near the auditory cortex—is smaller on the right side in people with AP. Neuroscientist Nadine Gaab of the Boston Children’s Hospital, who worked with Schlaug, speculates that “there may be a gene for this asymmetry, rather than an AP gene per se.”
A complex charm
Theusch describes her thesis work on AP as a puzzle of nature and nurture that she’d like to solve. “Music itself is such a cultural thing. It’s hard for some people to believe it might have genetic influences,” she says. “But I believe both collide when you study AP.”
Her research has musicians who don’t usually think about genetics wanting to learn more. Geneticists focused on studying diseases and traits with more negative connotations find her work an appealing change. Theusch also loves communicating with study participants, as “they’re so excited and curious about AP.”
Gitschier enjoys the fact that AP is a behavioral trait. Little research has been done so far on the genetics behind such traits, she notes, and not everyone feels comfortable opening this Pandora’s box. “I like rattling people’s cages on this,” she says. “I know it’s politically correct that [people] want to believe we’re all working with the same set of genes, but we’re not.”
Gitschier and Theusch also wonder whether the prevalence of AP differs with ethnicity, and if so, whether it has more to do with varying emphasis on early music training in different cultures, or genetic predisposition, or a dovetailing of the two. They’ll explore this further once they have a better genetic grasp of AP. “We don’t have a gene yet,” Gitschier says with a small sigh.
Funding is a problem for such studies, Theusch says, as well as finding enough “AP families” and getting them to provide DNA samples. Critics who don’t believe there’s any genetic basis for AP are another hurdle. For example, musician-turned-neuroscientist Daniel Levitin of McGill University in Montreal believes such genetic differences, if any, will be “extraordinarily subtle and difficult to isolate.” He’s mystified about what the UCSF researchers think the AP gene(s) might code for.
“What would be the supposed evolutionary advantage of having absolute pitch?” Levitin says. “Without an explanation for that, the research is only half-complete. Moreover, I don't see how they can expect to disentangle nature and nurture in this. Children with French-speaking parents end up speaking French themselves most of the time, but that doesn't mean there's a gene involved. So children of AP possessors have AP. So what?”
“We’re going to have to be very rigorous for people to believe us,” Gitschier acknowledges.
As I ponder these debates, the steady hum of my refrigerator—in B-flat—reminds me that writing makes me hungry. I suppose I’ll never hear that hum again without wondering what my AP gene(s) might be up to, and what’s really going on in my smaller right planum temporale—or the rest of my brain, for that matter. But that’s something for scientists and musicians alike to keep chewing on.
Top
Biographies
 Alissa Poh
B.Sc. (biochemistry with honors)
University of Bristol, U.K.
M.S. (pharmacology) Dartmouth Medical School
Internship: Boston Children's Hospital news office
Confession: I always read the ends of books first, preferring the big picture over finicky details. Hence my ill-starred romance with scientific research. After three years of wily cancer cells resisting my efforts to massacre them with drugs, and countless failed western blots, I felt quagmired in technical minutiae; I exited lab life rejoicing. Science journalism, rather than being a mundane job, strikes me as a promising, possibility-filled career. Many complete scientific stories elude those who remain hunched over microsopes in their isolated worlds, trying to unlock the mysteries of Protein X. I’m excited about donning the mantle of science writer, delving into these discoveries, and sharing what I find. Let me be a storyteller of science, rather than its slave.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
 Filipe Franco
B.A. (graphic design) Instituo de Artes Visuais,
Design e Marketing, Lisbon,
Portugal
After working in a variety of visual arts fields, I began to feel uncomfortable with the course my life was taking. I felt unfulfilled as a creative human being and started looking for a way to apply my artistic skills in a more useful manner. In the last four years, I have been acquiring knowledge related with the interaction between art and science. That is why I abandoned my professional career and invested in a graduate degree in Science Illustration. After completing the Science Illustration Program, I decided to delve further into the vast possibilities opened up by this interaction and chose a Forensic Art internship. I'm currently in Houston, Texas, at the Houston Police Department.
Top |
