Why music moves us

Writing in Nature, Daniel Levitin presents an excellent review of Philip Ball's newest book, "The Music Instinct: How Music Works and Why We Can't Do Without It". The science of music and musical perception is a topic that's always fascinated me, although I'm hopelessly out of touch with the topic since leaving the University of Toronto (and losing access to its music library). Philip Ball is a great writer (I haven't read his books, but his articles for Nature are always very well done) so this is a book that I really would like to pick up.

The most striking parts of the review deal with how the brain processes music by searching for a balance between simplicity and complexity. The review may not be accessible without a subscription to Nature, but I will excerpt the key passages here:

"... the music really starts to play when Ball introduces the US composer and music theorist Leonard Meyer. Meyer argued that music that is too simple or too complex is likely to irritate. The secret to composing a likeable song is to balance predictability and surprise. Because most music has a beat and is based on repetition, we know when the next musical event is likely to happen, but we don't always know what it will be. Our brains are working to predict what will come next. The skillful composer rewards our expectations often enough to keep us interested, but violates those expectations the rest of the time in interesting ways."

Cue up a series of articles extolling the virtues of melodically weird and complex music that manages to remain within the boundaries of pop, from "Good Vibrations" to 70's prog to Animal Collective's "Merriweather Post Pavilion". But I read that paragraph and found a closer connection to techno, or more broadly speaking, the interaction between a DJ and the crowd in a club. Tracks are recorded with ebbs, flows, and breakdowns that are meant to provide just the right kind of lift to a live crowd. The DJ enhances these elements of the song by, for example, dropping the beat, tweaking the EQ's, or mixing in sections (or samples) from other tracks. Everyone in the crowd knows and expects to hear these tricks every time they step into a club! It's OK to have a instinctual feeling about when the DJ will drop the beat onto the track. The beat kicks in when you expect it to, but maybe it's a killer beat so that's all right by everybody. Similarly, almost everybody loves a good breakdown. What people don't want to hear is exactly the same breakdown, exactly the same EQ tweaks, track after track for hours on end. They like knowing that a breakdown is coming, but what makes the experience truly special is listening to tracks (and DJ's) who can surprise you about when the breakdown will end.

Dancing in a club (the physical action of dancing, that is) follows these principles almost to a tee. People don't just stick to patterns, dancing in place and zoning out. They alter their motions with the rising and falling of the music. They are predicting where the music will go and are shifting their dancing style to match it. More on the brain as predictatron:

"In neuroscientific terms, the physical world presents our sensory systems with an ambiguity, and the brain — a giant prediction device — uses statistical principles and logical inferences to resolve that ambiguity and to predict what will happen next. Listening to music exercises our neural circuits by simultaneously rewarding them for correct predictions and challenging them to learn new principles for organizing the world. Music engagement might also promote creative, flexible thinking and hone prediction skills."