Consonantal voicing effects on vowel duration in Italian-English bilinguals

This project reported in this dissertation analyzes phonetic details of the speech patterns in one of New York\u27s bilingual communities, asking whether a bilingual speaker can attain native-like proficiency in both languages and the extent to which authenticity — maintenance of language-specific settings — is sustainable. Researchers have established that Italian and English differ strikingly in their characteristic time settings for vowel durations: durations are greater for vowels preceding voiced consonants, e.g., cab, rather than voiceless, e.g., cap. This duration difference, termed the consonantal voicing effect (CVE), is notably greater for English than for Italian. The greater magnitude of the CVE found with English is considered to be a phonological enhancement of a basic phonetic process. Utilizing a speech production task, the study reported compares the performance of Italian-born bilinguals for whom English was acquired in adulthood, as a second language, with that of U.S.-born speakers who experienced simultaneous acquisition of their languages (albeit in an English-dominant setting). In separate sessions for each language, speakers produced utterances in which the target word, situated inside a carrier phrase, contrasted in [voice] value for the post-vocalic consonant, e.g., Say the word « ___ » to me. Stimuli were familiar words selected to sample the vowel inventories for each language and for which the voicing contrast was realized through the inventory of stops common to both languages. Analyses revealed no evidence of influence of the second language on the CVE for the first language for either group, despite an extended immersion period in an English-language environment for the foreign-born speakers and simultaneous exposure to both languages from birth for the U.S.-born speakers. But crucially, there was evidence of an influence of the first language in the timing settings found for the CVE in the second language, for both speaker groups: the foreign-born speakers managed to increase the magnitude of the CVE-English but failed to fully implement the phonological mechanism consistent with larger CVE values for that language; and the U.S.-born speakers managed to reduce the magnitude of the CVE-Italian but failed to fully suppress that same mechanism. Results are discussed in relation to language-specific timing patterns and the extent to which a dominant language may influence production in the non-dominant language