How "proficient" is proficient? Bilingual listeners' recognition of English words in noise

Shi (2011, 2013) obtained sensitivity/specificity measures of bilingual listeners' English and relative proficiency ratings as the predictor of English word recognition in quiet. The current study investigated how relative proficiency predicted word recognition in noise.

Forty-two monolingual and 168 bilingual normal-hearing listeners were included. Bilingual listeners rated their proficiency in listening, speaking, and reading in English and in the other language using an 11-point scale. Listeners were presented with 50 English monosyllabic words in quiet at 45 dB HL and in multitalker babble with a signal-to-noise ratio of +6 and 0 dB.

Data in quiet confirmed Shi's (2013) finding that relative proficiency with or without dominance predicted well whether bilinguals performed on par with the monolingual norm. Predicting the outcome was difficult for the 2 noise conditions. To identify bilinguals whose performance fell below the normative range, dominance per se or a combination of dominance and average relative proficiency rating yielded the best sensitivity/specificity and summary measures, including Youden's index.

Bilinguals' word recognition is more difficult to predict in noise than in quiet; however, proficiency and dominance variables can predict reasonably well whether bilinguals may perform at a monolingual normative level.