Bilinguals have a single computational system but two compartmentalized phonological grammars: Evidence from code-switching

Abstract

Classic linguistic models, such as Chomsky’s minimalist schematization of the human language faculty, were typically based on a ‘monolingual ideal’. More recently, models have been extended to bilingual cognition. For instance, MacSwan (2000) posited that bilingual individuals possess a single syntactic computational system and, crucially, two phonological systems. The current paper examines this possible architecture of the bilingual language faculty by utilizing code-switching data. Specifically, the natural speech of Maria, a habitual Spanish-English code-switcher from the Bangor Miami Corpus, was examined. For the interface of phonology, an analysis was completed on the frequency of syllabic structures used by Maria. Phonotactics were examined as the (unilingual) phonological systems of Spanish and English impose differential restrictions on the legality of complex onsets and codas. The results indicated that Maria’s language of use impacted the phonotactics of her speech, but that the context of use (unilingual or code-switched) did not. This suggests that Maria was alternating between encapsulated phonological systems when she was code-switching. For the interface of morphosyntax, syntactic dependencies within Maria’s code-switched speech and past literature were examined. The evidence illustrates that syntactic dependencies are indeed established within code-switched sentences, indicating that such constructions are derived from a single syntactic subset. Thus, the quantitative and qualitative results from this paper wholly support MacSwan’s original conjectures regarding the bilingual language faculty: bilingual cognition appears to be composed of a single computational system which builds multi-language syntactic structures, and more than one phonological system.