This project brings together three distinct lines of research on variation in speech production. The first line of research concerns how consonants are articulated when they are at the beginning of a word or syllable, vs. at the end of a word or syllable. Initial consonants have more articulatory contact and in general more extreme articulations than do final consonants. The second line of research concerns how consonants are articulated in different positions in a phrase or utterance. Consonants at the beginning of a phrase or utterance have more articulatory contact and in general more extreme articulations than do consonants that come later in a phrase or utterance. The third line of research concerns large-scale trends in consonant and vowel articulation over whole utterances. It has been suggested that less articulatory effort is expended on consonants and vowels that come later in an utterance. The present project tests a hypothesis that unifies these lines of research: that articulations are more extreme at the beginning of units larger than a segment (syllable, word, phrases, utterance). This hypothesis will be tested in four languages: English, French, Korean, and Taiwanese. A series of experiments is proposed to compare articulations in different positions in different sized units. The primary dependent variable is tongue-palate contact as measured by electropalatography. Other measures include Voice Onset Time, nasal airflow and vocal cord contact as measured by electroglottography. Variation in articulation will also be compared to general trends in subglottal pressure and fundamental frequency. The significance of this project will be to develop something that has long been known in general but never worked out in any specific way: that the articulations of individual consonants and vowels depend on their prosodic positions. The results of the project will be relevant to researchers in linguistic phonetics, speech production, and speech technology.
