This Is Your Brain on Music: The Science of a Human Obsession

“Schema,” or frameworks formed on the basis of past experience, guide one’s expectations for a piece of music. The brain creates these schema by extracting features from past examples of similarly categorized experiences and stimuli, identifying essential components, and combining them into sets of expectations for future experiences. Skilled composers are like magicians, deliberately establishing and then violating expectations to evoke emotions in their audience. To do this, they use practically all characteristics of music, including timbre, rhythm, chord progression, meter, and even genre. The composer Haydn was particularly fond of deceptive cadence, a well-used illusion in Western music wherein a piece’s chord progression diverges unexpectedly from its established sequence to signal that the piece is not yet finished. Many modern classical composers base their pieces on new and unfamiliar scales, removing expectation and resolution from their music entirely and thereby leaving both the performers and audience ungrounded. Melody is one of the main channels by which composers control and diverge from audience expectations.