Bilingualism and visual word recognition

Resum

This thesis seeks to demonstrate that bilinguals can use the intrinsic characteristics of languages at sub-lexical level (i.e., orthographic regularities) to disentangle the language of words, prior to the activation of lexical entries in the lexicon. Moreover, it also seeks to characterise the extent to which the existence of different language detection mechanisms (sub-lexical and lexical) affect visual word recognition processes and cross-language interactions in different contexts. This thesis comprises ten experiments that vary in the demands of the task at hand, the language of operation, the level of language proficiency of the participants, and the technical approach used. Experiments are designed around three thematic axes: (A) Orthotactics and language identification [how orthographic regularities influence bilingual language detection and word identification]; (B) Time-course of language detection [the temporal unfolding of language detection in the presence or absence of sub-lexical language cues]; and (C) Orthotactics and cross-language activation [the impact of sub-lexical language information on the activation of lexical representations across languages]. The main findings derived from the work presented in this thesis suggest that despite the demands of the task at hand, the strategies used by the participants, and the language of operation, sub-lexical language information plays a critical role in bilingual word processing and in conscious and unconscious language detection. When bilinguals read words in both their languages they use a sub-lexical and a lexical route to access language membership information. Importantly, the sub-lexical route is automatically activated even when bilinguals are immersed in a single language context, whilst this does not seem to be the case for the lexical route. Moreover, language identity resolution via sub-lexical orthographic characteristics enables language selective mechanisms to emerge reducing unnecessary cross-language activation at the lexical level. Hence, the result of this thesis provides a comprehensive approach that helps us to better understand and characterise the processes underpinning bilingual visual word recognition. A modification of the most recent model of bilingual language processing (i.e., Bilingual Interactive Activation + extended model, Van Kesteren et al., 2012) is thus proposed at the end of this thesis in an attempt to account for all the work presented here and the results in the literature of visual word recognition in bilingual populations.