Schwa elision in fast speech: segmental deletion or gestural overlap?

Pretonic schwa elision in fast speech (e.g. potato --> [pt]ato, demolish --> [dm]olish) has been studied by both phonologists and phoneticians to understand how extralinguistic factors affect surface forms. Yet, both types of studies have major shortcomings. Phonological analyses attributing schwa elision to across-the-board segmental deletion have been based on researchers' intuitions. Phonetic accounts proposing that elision is best characterized as gestural overlap have been restricted to very few sequence types. In this study, 28 different [#CeC-] sequences are examined to define appropriate acoustic criteria for 'elision', to establish whether elision is a deletion process or the endpoint of a continuum of increasing overlap, and to discover whether elision rates vary for individual speakers. Results suggest that the acoustic patterns for elision are consistent with an overlap account. Individual speakers differ as to whether they increase elision only at faster speech rates, or elide regardless of rate. Phonotactic legality per se does not affect elision rates, but speech rate may affect the phonological system by causing a modification of the standard timing relationships among gestures.