The role of pitch in the vocal communication of intentions.

Intonation, the variation of pitch in speech, helps listeners understand speakers' communicative intentions. This study examines the role of pitch information at different levels of granularity-spanning specific (discrete contours), more flexible (general contour shape), and general (averaged pitch)-in communicating intentions. We first used a reverse correlation approach to identify people's mental representations of two contrasting intentions - criticism and suggestion - when listening to the word "beer." In a second experiment, listeners rated how much each resulting pattern sounded like criticism and suggestion. Statistical models revealed that listeners rely on the shape of the pitch contour in terms of its spikiness and overall pitch direction, in addition to mean pitch, while precise contour plays a minor role, supporting the relevant role of pitch dynamics as well as the inferential (rather than referential) role of intonation in communicating intentions. Notably, we found distinct groups of listeners who use pitch characteristics in different ways, highlighting both shared understanding (within groups of listeners) and substantial interindividual differences in processing social pragmatic cues. These findings clarify the role of pitch in intention communication, reveal its complexity, and highlight the potential for miscommunication in everyday interactions.