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 its 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 didnt 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 experiencesa phenomenon called neuroplasticity. This growing
field of research and its tantalizing possibilities piqued my
curiosity. Maybe theres really more to say about what I have than
vague descriptions like a musical ear. While Ive always known I
was different, musically speaking, its one thing to dwell in a world
foreign to most people, and another to understand how and why I got
there. Talent genes Its
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 advisors
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 its
genetic, or I wouldnt have bothered to work on this project. She
believes investigating genes that confer talent rather than cause
suffering is an equally important research area. Theres 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. Todays 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 papers 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 dont 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 Ive
had my whole life; I didnt work at it, and I thought everybody had
it. So its likely, Gitschier believes, that theres 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 geneticists 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 didnt stop there. In total, he distributed 900 surveys
to places ranging from the local UCSF Symphony and Michigans
Interlochen Center for the Arts, to Milans 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 Baharloos 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 notes
fundamental frequency with no overtones; its 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 didnt
meet our criteria unless they also scored well on the pure-tone
test. By "criteria," Gitschier
means AP-1, the studys 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. Thats 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 werent 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 isnt the whole answer, since early exposure
to music doesnt 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, personallyAP has been part of me since I started music
lessons at age four. Today, the gene
hunt continues. Gitschier and Theusch have now refined Baharloos
original auditory test. Theyre 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. Shes
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 dont know. What if I actually dont? 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 Ive 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 studys 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 its 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 its D rather than C. Gitschiers 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. Its
interesting, Gitschier says, that those with AP may provide a unique
window into such hearing changes. Think about visionas our lenses
harden with age, were probably perceiving colors a little differently,
but you wouldnt realize it unless you get cataract surgery, she
reflects. So were probably all hearing things sharper as we get
older, but you wouldnt 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 theres a single note musicians are familiar with, its Athe
universal tuning pitch. However, A can be tuned to different
frequencies; its 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. Thats 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. Hes 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
its 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 dont think its purely Mendelian, Drayna
counters, or we would see much bigger families with many more people
affected, the way hemophilia runs through Europes royal families.
Its not clear there is strong evidence either for or against this
straightforward inheritance pattern, he addsits more like we dont
know. But he thinks the UCSF team, by analyzing APs 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 neuroplasticityhow 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
dont 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 understoodwe
havent figured out how the brain stores different kinds of information
over time. You can always distinguish pink from red, and you dont
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 doesnt, but people with AP do. Specifically, Drayna believes that APas an add-on
in the brain rather than something gone awryprovides 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 temporalelocated near the
auditory cortexis smaller on the right side in people with AP.
Neuroscientist Nadine Gaab of the Boston Childrens 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 shed like to
solve. Music itself is such a cultural thing. Its 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 dont 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 theyre
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 Pandoras box. I like
rattling peoples cages on this, she says. I know its politically
correct that [people] want to believe were all working with
the same set of genes, but were 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. Theyll explore this further once they
have a better genetic grasp of AP. We dont 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
dont believe theres 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. Hes 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? Were going to have to be very rigorous for people
to believe us, Gitschier acknowledges. As
I ponder these debates, the steady hum of my refrigeratorin
B-flatreminds me that writing makes me hungry. I suppose Ill never
hear that hum again without wondering what my AP gene(s) might be
up to, and whats really going on in my smaller right planum temporaleor
the rest of my brain, for that matter. But thats 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. Im 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.
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