Impacts of Seeing Bilingual Children on Intelligibility Ratings

Purpose: Overall, seeing a speaker results in higher intelligibility than hearing speech alone because of visual speech cues. Intelligibility ratings of conversational speech samples provided by school-age bilingual children in two presentation modalities (i.e., audio only and audiovisual [AV]) were examined to determine whether there were other impacts of seeing the children. Method: Forty speech-language pathologists (SLPs) rated the intelligibility of conversational speech samples provided by 23 typically developing school-age children in three groups: bilingual Spanish–English, bilingual Mam–English (Mam is an Indigenous, Mayan language spoken in Guatemala), and monolingual English (control). In an online experiment, SLPs heard audio-only and AV recordings of individual 2-min speech samples in a randomized order. Data were analyzed using a linear mixed-effects model to determine if there were effects of presentation modality, speaker group, or accentedness on the intelligibility ratings. Results: No statistical differences were found between intelligibility ratings from the audio-only and AV presentation modalities. Accentedness was a significant factor on intelligibility ratings, whereas speaker group was not. Conclusions: SLPs rated conversational speech samples of bilingual and monolingual English-speaking children as having similar intelligibility, regardless of whether they listened to audio-only or AV recordings, even though visual speech cues should have caused a difference. Clinically, when SLPs use intelligibility ratings in their assessments of bilingual children's speech for speech sound disorders, it is vital to consider the influences of nonnative accent and linguistic bias. Supplemental Material: https://doi.org/10.23641/asha.30290560