Phonetic outcomes in Mandarin–English code-switching: exploring the role of orthographic depth

Prior research on the phonetics of code-switching has shown that bilinguals often experience short-term cross-linguistic interference, where the productions of one language shift towards the opposite language. Yet, these studies, most frequently employing a read-aloud paradigm, have focused primarily on language pairings in which both languages employ phonological alphabets, largely ignoring languages with more opaque links between orthography and phonology. More transparent links between orthography and phonology (e.g., phonographic systems) have been suggested to more robustly engage phonological pathways during visual word processing, relative to those with opaque links (e.g., logographic systems). The current study examines the potential for cross-linguistic phonetic interference during code-switching between English and Mandarin, languages that differ with respect to their degree of orthographic transparency. Employing a read-aloud paradigm, twenty Mandarin-English bilinguals produced target tokens in monolingual and code-switched speech. Analysis focused on the productions of the English low-front vowel [æ] and its Mandarin counterpart [e]. In contrast to most previous findings, the results of the current study revealed no observable phonetic interference in the code-switched speech relative to monolingual speech. The current research adds to the literature by discussing orthographic depth as a potential underlying factor in the expression of cross-linguistic phonetic interference.