The role of L2 experience in L1 phonotactic restructuring in sequential bilinguals

Languages differ in their phonotactic constraints – that is, the numbers, types and combinations of sounds that can occur together in different parts of a syllable. In Brazilian Portuguese, for example, no stop consonant may occur at the end of a syllable, and any syllables in violation of this constraint are repaired by inserting an epenthetic /i/. Similarly, word-initial /sC/ clusters are disallowed in Spanish and are modified with a prothetic /e/ before the cluster. These repair processes have been shown to occur in both production and perception. Previous work on L2-L1 crosslinguistic influence in speech has focused primarily on segmental effects. To address the issue of the L2-L1 effect on phonotactics, I examine production and perception of “illegal” consonant clusters in two populations of bilingual speakers: L1 Brazilian Portuguese/L2 English and L1 Spanish/L2 English. Both language pairings exemplify phonotactic constraint mismatches because English allows both syllable-final stops and word-initial /sC/ clusters. Previous work has shown that the phonotactics of both languages are active during speech perception and processing for early bilinguals. If the same is true for late bilinguals, then their L1 performance should be expected to show an effect of the less restrictive L2 English system compared to monolingual listeners. Two pairs of studies were conducted, one for each language combination: perception was assessed via a forced-choice non-word identification task, and production data was elicited with a sentence reading task. The results showed that whereas monolinguals perceptually repaired illegal consonant sequences with an illusory vowel in a vowel detection task, bilinguals were more faithful to the acoustic signal. In production, greater experience with English led not only to target-like production of these sequences in L2 English, but it also predicted lower rates of epenthesis in L1 readings. For the Portuguese/English subjects, perception and production in both languages were correlated, with higher accuracy in perception predicting less frequent epenthesis in production. These findings provide novel evidence of the interaction between the L2 and L1 in sequential bilinguals who began learning their L2 in adolescence and adulthood, thus extending previous findings on simultaneous/early L2 learners. The results suggest that even sequential bilinguals can acquire novel phonotactic constraints in an L2, and that this new knowledge modulates L1 performance. The results further suggest that the relationship between the production and perception modalities in bilinguals is not straightforward and may be modulated by language dominance. Implications for models of bilingual speech perception are discussed and directions for future research are suggested