Perfect pitch, more accurately called absolute pitch, is the ability to identify a musical tone without hearing any pitch as an external reference. It is largely innate talent, found in only about one in 10,000 people, according to Psychology Today. Even those who possess it naturally usually need musical training while young to maintain it. A few people develop it later in life, such as those with autism or other conditions that slow development.
Perfect pitch has genetic ties, as people with perfect pitch are likely to have other people with perfect pitch in their families, according to the University of California in San Francisco. Asians in particular are likely to have perfect pitch, according to Psychology Today. This is in part due to genetics and in part due to the tonal nature of languages such as Mandarin or Vietnamese, with words taking on different meanings when used at different pitches. Even with training, the ability diminishes in later years, the University of California at San Francisco reports.
People often confuse perfect pitch with relative pitch. Relative pitch is the ability to find any note once a reference note is established. Musicians can develop this with training, and often, they can memorize a certain frequently used pitch--middle C, for example--and find pitches from there. Most people have some level of pitch memory, as indicated by a study by Daniel J. Levitin, a researcher at McGill University. One of his experiments showed the people even without musical training generally sang popular songs near their original key.
People with perfect pitch face some difficulties. It can distract their enjoyment of listening to music, particularly when it's played in a different key than usual, making it sound "wrong" to someone with perfect pitch. Furthermore, learning relative pitch is difficult for some people with perfect pitch. This makes some musical tasks, such as transposing, difficult.
A number of famous composers, singers and musicians were born with perfect pitch. These include vocalists such Frank Sinatra, Ella Fitzgerald, Barbra Streisand and Julie Andrews; pop stars Mariah Carey, Celine Dion and Shakira; cellist Yo-Yo Ma and composer Leonard Bernstein. Having perfect pitch is hardly a prerequisite to musical success, however. Many highly regarded classical composers, including Peter Ilyich Tchaikovsky and Johannes Brahms, did not possess the skill.