Collaborative Research: Exploring Variation in English Intonational Acoustic Phonetics from Grammatical Perspectives

Spoken language consists of multiple streams of information – including a segmental stream (i.e., the consonants and vowels that make up words, suffixes, prefixes, etc.) and a suprasegmental stream (e.g., the pitch, amplitude, timing, etc. that define stress and cadence) which is often called "prosody". All speakers (consciously or not) know prosody can be used to communicate meaning – a single sequence of words can be pronounced many ways, often with importantly distinct meanings.

Despite this, most formal and computational linguistic investigations into meaning have primarily dealt with meanings encoded by the segmental stream (in words, suffixes, and prefixes). This project addresses this issue by exploring questions of how prosody and meaning relate. For example, what sorts of prosodic changes map onto changes in meaning?

And what sorts of meanings? To explore these questions, the research team makes use of contemporary empirical methodologies, analytic tools, and formal theories, and particular attention is paid to intonational aspects of prosody.

The project encompasses three sets of experimental tasks of speech production and speech perception. Each of these sets of tasks corresponds to a different domain of semantic/pragmatic meanings: Common Ground management, Information Structure signalling, and scope ambiguity resolution. Different semantic/pragmatic contexts correspond to different experimental conditions, and these contexts are presented to participants as visual, comic strip-like, stimuli.

These experiments measure prosodic characteristics of speech (e.g., pitch movements, coded with a recently developed annotation system called PoLaR) and/or reactions to speech (e.g., acceptability ratings). These data are then be subjected to quantitative analysis as well as to formal linguistic models to uncover how different meaning-based conditions and different prosodic patterns are related.

This work has important implications for improving human-computer interactions that are mediated by natural language, as well as for deepening understanding of various speech pathologies.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.