Altered auditory feedback
The role of the cerebellum in speech motor control of timing
The accurate production of speech relies on precise timing, as spoken language makes extensive use of timing differences to mark contrasts between words, stress, and phrasing, among other distinctions. This project investigates how impairments in two functions of the cerebellum cause particular types of deficits in speech timing in individuals with ataxic dysarthria. This project was supported by NIH grant F32DC019535.
Auditory feedback in speech motor control of timing
We work with the altered auditory feedback paradigm to examine the role of auditory feedback in monitoring and controlling temporal aspects of speech. We have found that speakers respond to shortened vowels by lengthening them, and may also be compensating for lengthened consonants with changes in the vowel as well. This provides support for previous arguments that speakers and listeners attend to and control proportional durations, rather than absolute durations.
Coordination of tone and segments
In my dissertation, I used the lens of lexical tone to examine the relationship between phonological association and phonetic realization. I built on work I did for my first qualifying paper, which explored the concept of an articulatory TBU, this time focusing on cross- and within-language variation in peak timing, working with acoustic and articulatory data from Central Thai and Serbian. I argue for an articulatory approach to the TBU, where both abstract association and concrete realization can be derived from coordinative relationships.
The role of the motor system and gestures in representation
I have also done some work on the role of the motor system in the representation and perception of speech, using both synchronic and diachronic data. How do we move from phonetic (acoustic) artefacts to fully phonologized gestures or features? This work leads to further questions about how learners acquire representations, and what stages do they go through on their way.