Abstract
Listeners show strong agreement on which tone should come next in an
unfamiliar melody. Cognitive models of expectancy often involve listener
responses to instrumental renditions of vocal melodies, and model
expectancy for the next tone on its pitch height relative to previous tones
in working memory. But if sung melodies encourage an expectation of
singability, then listeners should expect the next tone to fall within the
singer’s modal register regardless of preceding context. Nonmusicians heard
either sung or instrumental renditions of vocal melody fragments and made
retrospective goodness-of-continuation ratings on the final (probe) tone.
Half of the probe tones were within the modal register; half were above.
Ratings were modelled on a cognitive model based on pitch relations and a
singability model based on absolute pitch height alone. The cognitive model
best fit ratings on instrumental melodies but, as expected, the singability
model best fit ratings on sung melodies. Ratings were higher for sung
melodies than instrumental in the modal register, but lower for sung than
instrumental in the upper register. An alternative statistical learning
account based on probe tones’ novelty rather than singability was not
supported. Vocal constraints offer a sensorimotor framework for
understanding melodic expectancy in naturalistic song.