UC Santa Cruz

While traditional accounts characterize speech planning as serial, discrete, and walled off from behavior, newer proposals describe it as parallel, continuous, and delicately interweaved with execution. This dissertation evaluates the claim that speakers under time pressure produce articulatory trajectories that are graded fits to continually evolving partial, parallel constraints. In three form preparation experiments, motion-tracked digital video captured oral postures over time. Participants were sometimes primed with the nuclear vowels of CVC words. All words contained either /i/ (spread lips; e.g., “seed”) or /u/ (rounded lips, e.g., “soup”). In the first two experiments, initial consonants were highly uncertain. In Experiment 1, articulatory postures produced before stimulus presentation anticipated the upcoming vowel when it was primed. Experiment 2 included two pairs of vowel-primed blocks. The words of one /i/-block began with the rounded consonants /w/ or /r/ (e.g., “weak”). Primed vowels influenced anticipatory articulation except when superseded by conflicting demands from likely initial consonants. In Experiment 3, initial consonants were always bilabial, but words were blocked such that either vowel (/i/ versus /u/) or coda type (alveolar/lateral versus bilabial/labiodental) was initially uncertain. For example, a participant might know that an upcoming word would use an /i/ sound but not know whether the final consonant left the mouth relatively open (e.g., “meal”) or closed (e.g., “peep”). Analysis emphasized words ending in alveolar/lateral codas, and followed the evolution of articulatory trajectories over the acoustic phase of the utterance, in both horizontal and vertical lip aperture dimensions. Contrary to expectations, priming did not appreciably impact the shape of these two-dimensional trajectories.