"Let's sing karaoke!": Why do we sing out of tune?

The protagonist of the movie "Let's Go Karaoke!" is a gangster named Kyouji Narita. Because his boss holds a karaoke competition every year and the last place winner will be punished, Kyouji "invites" Satoshi Nagaoka, a member of a junior high school chorus, to teach him to sing at a karaoke bar in order to avoid being the last place winner in the singing competition.

This is a movie adapted from a comic book. From the plot to the characters, it is very "Japanese". Even karaoke originated in Japan. It is said that the reason for the emergence of karaoke is that if Japanese men go home too early after get off work, they will be looked down upon by their neighbors. They think that if they don't even have a social event, they must have bad interpersonal relationships. Therefore, many Japanese men will chat in bars and teahouses until late at night after get off work before going home. Later, they thought they should find something to kill time, so the form of singing in bars with TV microphones appeared.

Speaking of real karaoke, the inventor is Daisuke Inoue. When he was young, he worked as a drummer in a band. In order to facilitate performances, he invented a backing track and a portable microphone that separated the human voice from the accompaniment. Because of this invention, Daisuke Inoue also won the 2004 "Ig Nobel Prize" Peace Prize because this invention provided a new way for people to learn to tolerate each other. Giving the Peace Prize to this invention will make us all smile. After all, who doesn't have a few friends who sing out of tune?

In fact, the singing of Narita Kyouji in the movie is not that bad, but in real life, there are many people who are tone-deaf. Not only do they sing very badly, but they can't be taught. People who are out of tune can be divided into two types. One type can distinguish the difference in pitch, but can't sing it accurately. The other type lacks the ability to distinguish pitch. They can't distinguish the pitch, so of course they can't sing accurately. This symptom is called amusia or amusia.

Amusia is a disorder of musical pitch processing. Patients cannot recognize the difference between pitches and sing out of tune without noticing. According to surveys in different countries, about 3%-5% of people cannot distinguish pitches. The Montreal Amusia Diagnostic Test Group is mainly used to determine whether a person has amusia. The test content includes scale, contour, interval, rhythm, beat and memory recognition. Music ability is tested through two basic tasks: discrimination and recognition.

There are two main forms of aphrodisiac syndrome, one is congenital and the other is caused by acquired trauma.

People with congenital amusia have no hearing problems and normal intelligence. They have no brain damage, hearing loss or cognitive confusion, and they have no lack of contact with music. Babies are very sensitive to music. Even before they start talking, they can distinguish tones and discern dissonance in music. People with amusia cannot distinguish small changes in speech, such as different tones in spoken language, hearing "magic" as "shenqi" and "train" as "truck". However, this effect is not significant in Western languages ​​such as English and French, because these languages ​​are non-tonal languages ​​(Japanese used in movies is also non-tonal), while Chinese is a tonal language (with four tones). In Western languages, the distance between different pitches in intonation is usually more than six semitones, while the minimum distance of pitch difference in musical melody is one semitone. This difference in pitch distance results in the pitch perception defect of amusia not affecting speech perception.

The researchers also found that the tonality of a language has a positive effect on pitch recognition: people whose native language is a tonal language (such as Mandarin, Cantonese, Thai, etc.) have a higher sensitivity to pitch. For example, subjects whose native language is a tonal language are better than subjects whose native language is English in musical pitch imitation and perception. Scientists further speculate that a tonal language background may make up for the musical pitch defects of people with amusia. However, people with amusia who speak Chinese still have a lower ability to distinguish pitch than ordinary people, but semantic and situational clues can make up for their defects in distinguishing the high and low pitch of speech. Therefore, research on amusia can help us explore the relationship between music and language, and is also an important part of studying the uniqueness of Chinese.

Acquired amusia is mainly caused by brain damage and pathology. Some patients lose their ability to perceive music after a stroke. Scientists used magnetic resonance imaging to study the brains of patients with amusia. The results of the MRI scans confirmed their speculation that the auditory cortex on both sides of the brain of patients with amusia was damaged.

Using magnetic resonance imaging technology, scientists have also found that music is also very attractive to the deaf. In 2001, scientists from the University of Washington found that the auditory cortex of the deaf showed signs of activity when there was sound around them. Scientists believe that it may be because the vibration of the sound has an effect on the deaf, allowing them to "appreciate" music and feel the melody and rhythm of the music. Other research results show that when listening to music, not only the auditory cortex, but even the visual cortex is activated.

Back to the movie, in Let's Sing Karaoke!, we didn't hear Kuang'er's beautiful voice at the end, and even Congshi, who was the best singer, had to sing at full speed because of his voice change. But as the choir instructor in the movie said, the most important thing about singing is love. It doesn't matter whether you sing out of tune or not, what matters most is that you can bring happiness to yourself and others.

Written by Wang Richu, Institute of Psychology, Chinese Academy of Sciences