Effects of Native Phonology on Spoken Word Recognition and Second Language Phonological Processing

Abstract

The present investigation examined the effects of sociophonetic variation on word recognition and the acquisition of second language phonology. In norteño Mexican Spanish /tʃ/ undergoes a process of variation in which this sound may be produced either as an affricate, [tʃ], or a fricative, [ʃ]. Speakers of norteño dialect, thus, are likely to produce a word like charco ‘puddle’ as either [ˈtʃaɾko] or [ˈʃaɾko]. This produces an asymmetry between native Spanish speakers in Mexico: Norteño speakers have experience with both [ʃ] and [tʃ] in their native variety whereas speakers from central Mexico, whose dialect includes only one variant, [tʃ], do not. In addition, in Spanish [ʃ] and [tʃ] do not represent a phonemic contrast. Unlike Spanish, English possesses a phonemic contrast distinguishing between /tʃ/ and /ʃ/, as in cheat-sheet. The aim of this dissertation is twofold. First, this project investigates the effects of sociophonetic variation on the recognition of words by two groups of native Mexican Spanish speakers: one group of norteño speakers and one group of central dialect speakers (Experiment 1). The results from a lexical decision task with cross-modal priming show that both variants, [tʃ] and [ʃ], facilitate word recognition for listeners in both groups. Reaction times for target words preceded by primes with [tʃ] as the initial sound were faster. This suggests that the affricate variant is privileged over the fricative at some level of representation. Second, this dissertation explores and compares the perceptual behavior of the English phonemic contrast, /tʃ/-/ʃ/, by speakers of norteño and central Mexican Spanish who are learning English as a foreign language (Experiment 2). The results of a word-categorization task show that both groups of learners find cheat and sheet difficult to identify, but that norteño listeners find this task to be particularly challenging. The results of a categorical discrimination task show that all learners, but much more so the norteños, distinguish the members of the /tʃ/-/ʃ/ contrast only at chance level. Overall, the results of the present study suggest that the phonetic variants found in one’s native dialect do not affect the patterns of lexical activation in the native language, but they do modulate the perception of nonnative sounds. Finally, these results demonstrate that people who speak different regional varieties of the same language may face different obstacles when learning the sounds of their second language.