Science reports:

Your co-worker’s annoying humming may be more virtuosic than you think. People without musical training naturally improvise melodies that have hallmarks of tunes composed by professionals, a new study shows. It seems that most individuals follow the arcane rules of music composition, even those who are unaware those rules exist.

“It’s cool,” says Samuel Mehr, an expert on the psychology of music at Yale University who was not involved in the work. The study offers an “elegant” way to test people’s musical abilities. “It definitely feels like a real phenomenon, not some kind of contrived thing that a bunch of psychologists made up in the lab.”

The study concerns a musical concept known as tonality—the fact that songs almost always use a subset of all the pitches a voice or instrument can produce. For example, a standard piano has 88 keys, but the typical piano piece tickles just a fraction of them. If you play a piano’s keys one by one from left to right, the notes will climb steadily in pitch until the 13th note sounds just the same as the first note, only higher. This defines an octave.

Melodies usually stick to the same four to seven pitches in each octave that are called the scale notes. That is why, in the classic movie musical The Sound of Music, the von Trapp children learn just the seven notes “Do Re Me Fa So La Ti Do” of the most common type of scale in Western music. Out-of-scale pitches can sound jarring, but musicians sprinkle such “accidentals” into tunes to add elements of tension, color, and surprise (such as the middle syllable of “Maria” in this song from West Side Story). One note in the scale, the tonic, acts as the central pitch, which often starts and ends a song.

Tonality appears in music across diverse genres and cultures, though the scales differ greatly between, say, Indian classical and American folk. In part because of this ubiquity, some researchers suspect tonality might be an evolved human trait, which helps our brains perceive, remember, and create music. But it remains unclear how—or how well—average people understand tonal rules. [Continue reading…]