After six years of oboe lessons, I still sounded like a drowning duck. My high school band director insisted that if I only practiced more diligently, I’d eventually be like my stand partner, an all-state oboist who did not sound in the least like suffocating water fowl. In some ways, the differences between our abilities were differences of degree: if I practiced more and tried harder, my fingers might move quickly enough to play allegro triplets, too. But our differences were also differences in kind: she could tell when I was sharp or flat intuitively, without any reference pitch. She seemed to have some kind of extra-terrestrial superpower. I couldn’t imagine how anyone could do that.

Dr. David Ross ’99 GRD ’04 MED ’05, a fourth-year psychiatry resident in the School of Medicine Department of Psychiatry, is currently investigating the phenomenon of absolute pitch perception. He aims to differentiate between the two competing theories of the origin of perfect pitch: the innate model and the early learning theory.

There seems to be strong evidence in favor of each. Stephen Mulligan ’10, pitch for the a cappella group The Yale Alley Cats, has had perfect pitch for as long as he can remember. He started playing violin at age five, tutored by his father, a violinist for the Baltimore Symphony. “My dad would turn on the metronome to the A440 pitch for me to tune the violin,” explained Stephen referring to the frequency of an A commonly used as a reference note. “He realized I had perfect pitch when I finally asked, ‘Why do I need that when I’m tuning?’”

But it doesn’t work that way for everyone. Lucy Fitz Gibbon ’10, a member of the Schola Cantorum chamber choir, also started playing violin at age five, but she needed to tune her violin to the metronome. As she got older, however, she noticed that she could always remember and recreate the first pitch of her choral pieces. Now, she explains, it seems like different pitches have unique identities. “If your brain could feel things with its fingers, they’d all have a different texture to them.”

Ross suggests that the colloquial term “perfect pitch” is used to describe two very different phenomena. Some people with perfect pitch have an innate “ability to perceptually encode” (APE) pitch information in a way that is inaccessible to people without this trait. He calls this true absolute pitch. Everyone else with perfect pitch just has a really good memory for pitches, a “heightened tonal memory” (HTM). Heightened tonal memory is largely based on early learning, but there’s an innate component to it too — which is why not everyone with early musical training develops a form of perfect pitch.

If this distinction is correct, then people with heightened tonal memory should express a perfect pitch that varies based on their initial musical training. For instance, they would be better at naming notes produced by their primary instrument. “We had one subject who could only name the notes that he could pretend to play on the French horn,” Ross explains.

On the other hand, people with true absolute pitch should be able to identify all kinds of pitches, independent of their musical training — even those outside the musical domain. “It can get distracting sometimes” says Fitz Gibbon. “I’ll be listening to a lecture and suddenly I’ll start thinking about how the professor speaks in Ds and Es. Everything has a pitch: footsteps, car alarms, sometimes the faucet. And it can get annoying when things are out of tune. A fluorescent light, for instance, might be just shy of a B flat. That’ll drive me nuts.”

Ross has developed a novel paradigm to better characterize the distinction between HTM and APE. Subjects in the experiment — people with perfect pitch, people without, and those who are not sure — sit in front of a sign-wave generator, a machine that produces tones of varying frequency as you twist the dial. The subject hears a target tone and then a gap of variable length, which is either silent or contains a series of distracter tones. Finally, the subject is prompted to try to reproduce the target tone using the generator.

When I went to consult Ross, he sat me down in front of the generator and handed me a blindfold and a pair of Bose headphones. Fiddling with the laptop that generated the stimuli, he explained, “For people with true AP, this task is boring. They’re like, ‘why are you bothering me with this?’ Their responses are incredibly accurate and incredibly precise. People with heightened tonal memory can do pretty well on the task, but they really struggle. You see them sweating.” He scanned the pre-experiment questionnaire I’d filled out, which asks subjects whether they think they have perfect pitch. I didn’t. This was going to be nearly impossible. “Just let go of your type-A tendencies,” he suggested.

Currently, Ross is testing children on the pitch-matching experiment at an age when they have not yet had significant musical training. If he can identify kids that respond to the test in a way that is characteristic of true absolute pitch, he will find evidence to support the innate model.

Since he has begun testing kids, Ross has been consulted by a few parents who bring their children. The parents are worried that their children have autism because they spend so much time at the piano. The kids don’t have autism; they have true absolute pitch. So Ross tells the parents to think about it this way: “Imagine if you took 10,000 children and placed them in front of easels with paint and paint brushes. Now imagine that 9,999 of them are color blind. Well, one of the kids would seem to be interested in a way that none of the others were. He would seem to be getting more out of the experience than the others. This is what the kids with absolute pitch look like with music.”