Behavioral evidence of a harmonic surprise effect on preference in popular music

Recent statistical studies have suggested a relationship between increased harmonic surprise and music preference. Conclusive behavioral evidence to establish this relationship is still lacking. We set out to address this gap through a behavioral study using computer-generated stimuli designed to differ only in contrastive and absolute harmonic surprise. We produced the stimuli with both experimental control and ecological validity in mind by engaging the help of studio musicians. The stimuli were rated for preference by 84 participants (44 female, 40 male) between 18 to 65 years old. Participants rated items featuring moderately increased absolute and contrastive surprise significantly higher than items with lower harmonic surprise. This effect applied only to levels of surprise within a range typically found in popular music, however. Excessive surprises did not yield an increase in preference. We discuss different mechanisms of consistency and how they may mediate the selection of neural strategies leading to preference formation. These findings provide evidence of a causal behavioral relationship between harmonic surprise and music preference.