Neuronal activity to environmental sounds when presented together with semantically related words : An MMN study on monolingual and bilingual processing of homophones

Abstract: Neuronal activity of monolingual and bilinguals to environmental sounds and words that are semantically related to them were studied using the mismatch negativity (MMN) component of event-related potentials. MMN was expected to reflect the language selection process in bilinguals on the bases of semantics and phonology. In this regard, as lexical stimuli, interlingual homophones ‘car’ and ‘kar’ (snow) were presented together with semantically related environmental sounds in a passive auditory oddball paradigm. The lexical stimuli were recorded by a native English speaker. Three Turkish-English late bilinguals and one native English speaker participated in the study. An early MMN was elicited in both groups with a distribution over the fronto-central and central areas across the scalp with highest peak amplitude at -2.5 with a 113 ms latency. This response indicates that participants of the study were sensitive to the acoustic changes in two different types of stimuli. The further investigation of the interplay between environmental sounds and semantics displayed no conclusive result due to lack of data. Finally, the brain responses gathered from the bilinguals were not enough to draw a conclusion. Whether the bilinguals were sensitive to the sub-phonemic cues in the presented auditory lexical stimuli or not were inconclusive.