UC Santa Cruz

Vowel insertion commonly occurs cross-linguistically to break up consonant clusters, particularly in loanwords. The most familiar form of this insertion is the categorical, phonological process of vowel epenthesis, which repairs syllable structure violations. However, gradient, phonetic vowel insertion also occurs in many languages. This phenomenon, known as vowel intrusion, occurs when speakers employ a gestural timing that results in an open transition between the consonants in the cluster. The resulting intrusive vowel is not a phonological segment, and therefore lacks gestural and durational targets.

This dissertation presents a case study of vowel intrusion in Turkish onset clusters, which occur in European loanwords. The non-lexical vowels in these clusters have previously been described as epenthetic vowels whose quality is categorically determined by the following lexical vowel, in a process of regressive vowel harmony. I present new evidence from experimental, corpus, and elicitation data, that the non-lexical vowel in Turkish onset clusters lacks a gestural or durational target, and does not form a syllable nucleus—distinguishing characteristics of intrusive vowels. Gestural and acoustic data comes from an ultrasound production study, which shows that the non-lexical vowel is gradiently present; does not achieve the same gestural and durational targets as lexical vowels; and is more affected by coarticulation.

A corpus study extends the investigation to other types of consonant clusters, and finds that the effect of the consonantal environment on the non-lexical vowel can be seen even in broad transcriptions. I also probe the syllabic and metrical status of using two studies of text-setting of /CC/ words. These studies reveal that is more variable and less likely to receive a beat than lexical vowels.

This evidence supports an analysis of Turkish /CC/ words as beginning with onset clusters. I present a coupled oscillator representation of vowel intrusion and onset clusters, using Optimality Theory and allowing the phonology to refers to both segments and gestures. I also argue that Turkish has historically been reanalyzed as an underlying vowel, but that language-internal variation, as well as increasingly prevalent knowledge of source languages, today maintain its status as an intrusive vowel.