Psychologists have understood that people prefer things they’ve experienced before at least since Robert Zajonc first demonstrated the ‘mere exposure effect’ in the 1960s. It doesn’t matter whether those things are triangles or pictures or melodies; people report liking them more the second or third time around, even when they aren’t aware of any previous exposure. People seem to misattribute their increased perceptual fluency - their improved ability to process the triangle or the picture or the melody - not to the prior experience, but to some quality of the object itself. Instead of thinking: ‘I’ve seen that triangle before, that’s why I know it,’ they seem to think: ‘Gee, I like that triangle. It makes me feel clever.’ This effect extends to musical listening. But evidence has been accumulating that something more than the mere exposure effect governs the special role of repetition in music.
In fact, repetition is so powerfully linked with musicality that its application can dramatically transform apparently non-musical materials into song.
You can buy the author’s book, ‘On Repeat: How Music Plays the Mind,’ here: amazon.com