Date of Degree
Speech Pathology and Audiology
bilinguals, monolinguals, semantic context, context use, age of acquisition, speech recognition in noise, second language
Introduction: Previous literature has shown that bilingual listeners face more challenges than monolinguals during speech recognition in adverse listening conditions. As noisy environments degrade the acoustic stimuli and leave the listener with a partial or ambiguous signal to pair to a lexical representation, it is not possible to do so with the acoustic and phonological features alone. Bilinguals consistently use a significant amount of their cognitive resources during the early stages of speech processing, partially due to their need to navigate between the two languages. With exhaustion of most of their cognitive resources, there is limited capacity available to use higher-order processes, such as linguistic knowledge or semantic context in order to facilitate accurate recognition of the input signal when in noisy environments. The goal of this review was to determine the effect of linguistic background on the use of semantic context to enhance second language (L2), particularly English, speech recognition in adverse listening conditions. More specifically, this review examined the use of semantic context to enhance speech recognition by both bilinguals, with different Age of Acquisition (AoA), as well as monolinguals when listening in noise.
Methods: 12 studies that investigated the use of semantic context to enhance speech recognition in monolingual and bilingual listeners were selected for this review. We were specifically interested in bilinguals with English as a L2.
Results: Of the 12 studies included in this review, seven studies assessed monolinguals and bilinguals. Of these seven studies, five found that monolinguals were able to use semantic context clues better than bilinguals to facilitate accurate speech recognition in noisy environments. Most of the studies which pointed to poorer semantic context use in bilinguals evaluated subjects with later AoA. In addition, five of the 12 studies assessed the effects of AoA of the L2. Four of these studies determined that bilinguals with earlier AoA are better able to use semantic context to facilitate speech recognition in adverse listening conditions.
Discussion and Conclusion: As the definition of bilinguals and bilingual subgroups vary according to different researchers, it is difficult to analyze the results without consideration for AoA. Analysis of our results suggest that bilingual use of semantic context is modulated by AoA. Most of the literature reviewed that points to poorer semantic context use in bilinguals compared to monolinguals used bilingual subjects with late AoA.
Conclusion: It seems that the earlier the AoA, the better bilingual individuals are able to use semantic context to facilitate speech recognition in noisy environments.
Abucasis, Rachel, "Monolingual Versus Bilingual Use of Context to Facilitate Speech Recognition in Background Noise: A Systematic Review" (2022). CUNY Academic Works.