Phonological non-selective access in cross-script bilinguals: a masked priming event-related potentials (ERP) study

Abstract

The issue of bilingual lexical non-selectivity, whether automatic co-activation of two languages in a bilingual when input of only one language is present, has been contested by various bilingual word recognition theories. This study examined how bilingual lexical representations are organized, and more specifically whether sublexical and lexical phonological representations of two languages differing in orthographic script are automatically activated and integrated in one or separate lexicons. Prime-target pairs varying factorally in phonological and semantic similarity were used to compare phonological and semantic priming effects between Korean-English bilinguals and English monolinguals in a masked priming lexical decision task. For bilinguals, behavioural mixed-effects modelling analysis indicated that shared phonology between two languages showed inhibitory effects while the overlap in meaning facilitated target word recognition compared to monolinguals. Phonologically similar prime-target pairs also evoked a greater positivity at the early central-right P2 component, but reduced negativity at the lexical N400 than phonologically dissimilar pairs in bilinguals. Whilst words with semantically similar primes led to an earlier peak latency and reduced activation at the late central N400, suggesting that shared phonology and meaning between Korean and English facilitate the ease of lexical-semantic retrieval and post-lexical processing during L2 word recognition. More effortful processing for phonologically similar pairs at the P200 suggests that automatic and non-selective activation of shared L1 and L2 phonology is inhibitory at the sub-lexical level, and becomes facilitatory as competition is resolved at the lexical N400 level. In general, the findings lend support to the Bilingual Interactive Activation Model (BIA+), which argues for co-activated and shared L1 and L2 sub-lexical and lexical phonological representations. However, to account for the phonological interference effects from orthographically distinct scripts, additional links to the language node from sub-lexical representations and accommodation to the degree of overlap between orthography and phonology between L1 and L2 are proposed.