Abstract/Summary

The twenty-first century is witnessing a shift in attitude towards the acquisition of more than one language. Bilingualism that was once considered to lower the intelligence of the 'afflicted' is now being suggested as contributing to better cognitive abilities, and delaying the onset of dementia. The other pressing issue that the 21st century is facing in many parts of the developed world is a rapidly ageing population. Thus, the present study examined the effects of age(ing) and bilingualism on two important aspects of human life: our ability to infer nonliteral meaning (i.e. pragmatic inferences) and executive functions (EF). The present study also explored the relationship between pragmatic inferences and executive functions, and has documented a small number of case studies on EF and pragmatic inferring in AD. Four groups of participants made up of young {17 -23 years) and old {60- 83), and monolinguals (English speakers in the UK) and bilinguals {English-Tamil speakers in Singapore) were put through a set of linguistic tasks (pragmatic inferring tasks that included nonconventional indirect requests, conventional metaphors and novel metaphors) and non-linguistic tasks (Simon, Stroop Arrow, Spatial N-Back, ColourShape etc.) that recorded the participants' pragmatic inferential abilities and executive functioning (namely, inhibition, updating and switching). The present study has found that there was a bilingual advantage in pragmatic inference-making for some nonliteral language types. There was an age effect on pragmatic inferencemaking, but, again, not for all nonliteral language types. There was no bilingualism effect on executive functions, but young bilinguals were found to have a smaller Mixing Cost than the young monolinguals and old bilinguals, presumably due to their greater code-switching frequency. An age effect w.a s found for inhibition (where old participants obtained better accuracy scores than the young) and updating, but none for Switching/Shifting, except for the Mixing Cost. It was also found that updating was predominantly a significant contributor to pragmatic inference-making. And lastly, there were relationships between updating and pragmatic inference-making, but only for some non literal language types and that too, for bilingual participants. While past studies have found effects of bilingualism in inhibition, the present study has shown that updating seems to be an important EF resource for bilinguals in discourse processing. In addition, as predicted in the study, frequent code-switching contributed positively to better global sustained control mechanisms.