The Bidirectional Acquisition of Oral and Nasal Gestural Timing in L2 Brazilian Portuguese and Rioplatense Spanish Nasal Structures

Brazilian Portuguese (BP) nasal vowels (Ṽᴺ) and Rioplatense Spanish (RS) vowel + nasal sequences (VN) are realized with two oral (vowel and consonant) gestures and a nasal (velum) gesture, but they differ in the way these gestures are sequenced. Adult native speakers of RS and BP who aim to acquire the opposite language will thus need to learn this cross-linguistic difference. On the one hand, non-native speakers of BP will have to realize a longer overlap of the vowel and velum gestures and a shorter nasal coda. On the other hand, non-native speakers of RS will need to produce a shorter gestural overlap and a longer nasal coda. The main purpose of this dissertation is to investigate the relative difficulties that RS and BP speakers encounter at the phonetic and phonological levels when acquiring the gestural pattern of the other language’s nasal structure. To accomplish this goal, four studies were conducted. The findings from the studies on monolingual and bilingual production suggest that nasal structures in RS and BP are similar but differ in terms of their gestural timing and that their phonetic implementation and phonological representation may be affected by the dominant language of heritage speakers. Moreover, the studies on naïve and L2 perception and production indicate that, with experience in the L2, the timing of the oral-nasal gestural overlap can be acquired by non-native speakers. However, the gestural timing of a longer nasal coda seems more difficult to realize than that of a shorter nasal coda, not only at first exposure but also with more experience in the L2. This suggests that nasal coda weakening, a common phonological process in language variation and change, poses less articulatory difficulties to L2 learners than nasal coda strengthening. We propose that a gestural timing constraint on nasal coda strengthening should be integrated into L2 models of phonological acquisition to better predict and explain relative difficulties encountered by L2 learners.Ph.D