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Perfect pitch, explained

Perfect pitch refers to a person’s ability to identify any musical note by name after hearing it, without reference to other notes. Perfect pitch—also known more technically as absolute pitch—can also refer to the ability that some singers have to sing a given note on cue.

Though perfect pitch was thought to be a rare ability that depended primarily on early musical training in a “critical period” of sensitivity in childhood, auditory learning studies at the University of Chicago and elsewhere have shown that some individuals can learn to identify musical notes by ear even later in life.

What is perfect pitch?

Perfect pitch refers to a person’s ability to identify a musical note correctly upon hearing it. For example, if someone were to play the note C sharp (C#) on the piano, a person with perfect pitch would be able to name the note without having seen which key was struck. Singers with perfect pitch may also be able to sing a given note on cue, without having heard it.

Famous musicians including Ella Fitzgerald and Wolfgang Amadeus Mozart had perfect pitch, which has been considered a rare ability. However, research conducted at the University of Chicago on the science of auditory learning has complicated the idea that perfect pitch is an all-or-nothing ability that only a select few can acquire if they learn music early in life during a “critical period” of sensitivity. Instead, it can be developed even in adulthood, and may depend on more general auditory and cognitive abilities.

What is the difference between perfect pitch, absolute pitch and relative pitch?

Perfect pitch and absolute pitch are essentially the same concepts. Perfect pitch is an informally used term, whereas absolute pitch is a more technical term frequently used in research about the science of auditory perception. Both terms refer to a person’s ability to identify a note played out loud without seeing how it was played on an instrument and without reference to another note. Perfect pitch may also refer to the ability to produce a given note on cue by singing.

Relative pitch differs from perfect/absolute pitch in that people with relative pitch can identify notes, but only in reference to one another. For example, by using solfège—in which the syllables do, re, mi, fa, so, la, ti, do are applied to the notes in a scale—a person can determine how much higher or lower one note is relative to another. Relative pitch is more common among musicians than perfect pitch.

Both people with perfect/absolute pitch and people with relative pitch can often play music “by ear,” meaning reproducing a song only by hearing it. However, those with perfect/absolute pitch can always tell whether a song has been transposed into another key from its original recording, whereas those with relative pitch may not have this ability.

Can you learn perfect pitch?

People can, indeed, learn to identify musical notes by ear, but there are some caveats.

Previously it was thought that acquiring perfect pitch depended on a “critical period” early in life during which children could acquire perfect pitch with training, or that only some children with a specific genetic endowment could acquire perfect pitch during this period. Adults, it was thought, could not acquire perfect pitch once that developmental window closed.

However, a 2013 study argued that a drug called valproate could ‘re-open’ this critical period, allowing some adults to learn to identify notes by ear with training. Later research conducted at the University of Chicago by Prof. Howard Nusbaum, Shannon Heald, Stephen Van Hedger, and Rachelle Koch showed that drugs may not be necessary: With only brief training, some adults learned to remember notes, and could correctly identify them even months later with higher accuracy than they had been able to beforehand.

While only a few individuals may become as accurate as individuals who have had absolute pitch their entire lives, according to Nusbaum, ‘perfect pitch’ may be more malleable than previously thought. Having perfect pitch is likely related to a person’s auditory working memory—in other words, their ability to remember and assign meaning to sounds such as musical notes.

Other research by Van Hedger, Heald and Nusbaum demonstrated that even those with absolute pitch can be re-tuned, or ‘tricked’ into thinking that music is in tune when it is in fact out of tune, if they first listen to a piece of music that is gradually detuned by a third of a note over the course of several minutes.

A person’s first language and previous experience with music and sound may also influence their ability to identify musical notes and their likelihood of having perfect pitch. For example, some evidence suggests that speakers of tonal languages—such as Mandarin—in which the same word can have different meanings depending on the tone in which it is spoken (where tone refers to sound frequency or pitch, rather than emotional quality), may be more likely to develop the ability. Those who learned to play instruments from an early age may also be more likely to have perfect pitch.

The best predictor of perfect pitch, according to recent research from Nusbaum’s lab led by doctoral student Katherine Reis, is a brain response measure called the “frequency following response,” which provides a snapshot of the overall integrity of a person’s ability to process and classify sounds.

The caveat, however, is that the frequency following response itself is not immutable. Though it might seem “fixed,” individuals can improve this response with practice, and both individuals with and without perfect pitch are better at naming notes produced on a piano, as opposed to computer-generated sounds, suggesting that familiarity with the timbres of musical instruments is important.

How rare is perfect pitch, and is it genetic?

A commonly cited number is that approximately one in 10,000, or .01% of people, are thought to have perfect pitch. However, perfect pitch may actually be considerably more common: One recent review suggested that 4% of music students have the ability, and people with perfect pitch can be found in the general population, if you know how to look for them, according to Nusbaum, a leading expert on the science of auditory learning.

Research at the University of Chicago has also suggested that perfect pitch may not be an inherent, immutable skill, because some people can learn to identify notes with training, while those who have perfect pitch can be “tricked” with re-tuning. Still, there is variability in people’s ability to identify notes by ear, both with and without training, that could be due to environmental, genetic or neurological differences, such as auditory working memory and the frequency following response.

Nusbaum believes that whether a person has or can acquire perfect pitch may be a combination of their musical training and their general capacity for auditory working memory and perceptual attention. For example, while some people who were experimentally trained to memorize notes over an eight-week period ultimately achieved the same level of accuracy as those who naturally had perfect pitch, others did not.

What have studies of perfect pitch taught us about auditory learning?

Scientists studying perfect pitch at the University of Chicago have contextualized their research within psychology as part of a growing body of evidence that challenges the notion that people’s abilities are innate, genetic endowments: Instead, they argue, these abilities are more flexible. In the case of auditory learning—languages, music and other sounds—this means that people may be more able to develop their abilities later in life than previously thought.

According to Nusbaum, who has studied auditory learning for years: “The way you start learning something changes the way you pay attention to it.” If people are forced to learn a new language through immersion, for example—because they are isolated from fellow expatriates, or because their livelihoods depend on it—they are more likely to become fluent much more quickly than those who are not required to pay attention in the same way, who can get by without doing so.

Nusbaum describes this tradeoff as arguing against the “critical period” theory, which proposes that humans have limited developmental opportunities to acquire new skills, and supporting the “critical mass” theory, which proposes that the amount of learning that takes place over time can affect the level and type of attention that a person has paid to a particular area of knowledge. Thus, practice and immersion play an important role in skill development: Practice, in a sense, really does make “perfect.”