This study investigated cognitive and emotional effects of syncopation, a feature
of musical rhythm that produces expectancy violations in the listener by
emphasising weak temporal locations and de-emphasising strong locations in
metric structure. Stimuli consisting of pairs of unsyncopated and syncopated
musical phrases were rated by 35 musicians for perceived complexity, enjoyment,
happiness, arousal, and tension. Overall, syncopated patterns were more enjoyed,
and rated as happier, than unsyncopated patterns, while differences in perceived
tension were unreliable. Complexity and arousal ratings were asymmetric by
serial order, increasing when patterns moved from unsyncopated to syncopated,
but not significantly changing when order was reversed. These results suggest
that syncopation influences emotional valence (positively), and that while
syncopated rhythms are objectively more complex than unsyncopated rhythms, this
difference is more salient when complexity increases than when it decreases. It
is proposed that composers and improvisers may exploit this asymmetry in
perceived complexity by favoring formal structures that progress from
rhythmically simple to complex, as can be observed in the initial sections of
musical forms such as theme and variations
