Audiovisual enhancement in the perception of children’s speech

It is nearly axiomatic that audiovisual (AV) speech is more intelligible than audio-only (A-only) speech, particularly when the speech is presented in a challenging listening environment, such as in background noise [e.g., MacLeod and Summerfield, Br. J. Audiol., 2 (1987)]. No previous research on audiovisual speech perception has examined the perception of children’s speech. Children may elicit a smaller AV benefit than adults, as their visual articulatory movements are more variable than adults’ [e.g., Smith and Goffman, J. Speech Lang. Hear. Res. 41 (1998)], and hence are less informative perceptual cues. Alternatively, the overall lower intelligibility of children’s A-only speech might lead them to elicit overall higher AV benefits than adults. To examine this question, we collected developmentally appropriate sentence productions from five, 4-6 year old children, and five sex-matched adults. Ongoing work is examining the intelligibility of these sentences in multitalker babble in A-only and AV conditions in a variety of signal-to-noise ratios, so that we can compare AV benefits for children and adults when A-only intelligibility is matched. Both sentence intelligibility and eye gaze during perception are being measured. Results will help us understand the role of individual-speaker variation on the magnitude of AV benefit.