| That a listener's first language affects the perception of a second language is generally undisputed. Linguistic experience has been shown to affect the perception of non-native segmental contrasts, phonotactics and prosody. In addition to linguistic experience, acoustic effects of coarticulation influence adult speech perception. For example, nasalization of vowels has been shown to affect the perception of vowel height due to its spectral consequences in the region associated with vowel height (Krakow et al., 1988; Ohala, 1986; Wright, 1975).;In spite of the influence of coarticulation on speech perception, some studies provide evidence that listeners may factor out these coarticulatory effects in certain contexts (Krakow et al., 1988; Ohala 1981, 1983, 1996; Mann, 1986). Krakow et al. (1988), for example, showed that English speakers were able to perceptually factor out the acoustic effects of nasal coupling when they were able to attribute such effects to an adjacent tautosyllabic consonant. What remains unclear is whether they were able to perceptually "undo" the coarticulatory effects of nasalization due to universal perceptual mechanisms (Mann, 1986) or due to linguistic experience with contextual nasal vowels (i.e. nasal vowels followed by a tautosyllabic nasal consonant) but not noncontextual nasal vowels (i.e. nasal vowels not followed by a nasal consonant).;The purpose of this dissertation is to investigate whether coarticulatory influences of nasalization are universal or dependent on language experience. Brazilian Portuguese and Spanish present the opportunity to test these hypotheses, since Portuguese has allophonic and (surface) contrastive nasalization (Wetzels, 1997) and Spanish does not have phonological nasalization in any context (Sole, 1992). Adult speakers of Spanish and Brazilian Portuguese were tested on their perception of the /u/-/o/ contrast in three conditions: oral ([gus]-[gos]), contextual nasal ([guns]-[gons]) and noncontextual nasal ([gus]-[gos]). Results indicate that coarticulatory influences of nasalization are language dependent. Implications for diachronic language change and second language acquisition of phonology are discussed. |
