Is it or isn't it: listeners make rapid use of prosody to infer speaker meanings.

A visual world experiment examined the time course for pragmatic inferences derived from visual context and contrastive intonation contours. We used the construction It looks like an X pronounced with either (a) a H() pitch accent on the final noun and a low boundary tone, or (b) a contrastive L+H() pitch accent and a rising boundary tone, a contour that can support contrastive inference (e.g., It LOOKSL+Hlike a zebraL-H%… (but it is not)). When the visual display contained a single related set of contrasting pictures (e.g. a zebra vs. a zebra-like animal), effects of LOOKSL+H emerged prior to the processing of phonemic information from the target noun. The results indicate that the prosodic processing is incremental and guided by contextually-supported expectations. Additional analyses ruled out explanations based on context-independent heuristics that might substitute for online computation of contrast.