An exploration of why preschoolers perform differently than do adults in audiovisual speech perception tasks

Preschoolers' perception of audiovisual speech is considerably less influenced by visual information than adults'. We test the hypothesis that experience correctly producing consonants plays a role in developing the underlying representation which mediates the perception of visible speech. We divided preschoolers into two groups: those who made substitution errors and those who did not. Using a newly developed methodology, we tested substituters, nonsubstituters, and adults in an auditory-only condition, a visual-only condition, and an audiovisual condition. There were no differences among groups in the auditory-only condition. Overall, children still showed less visual influence than adults. Among the children, substituters were poorer at lip-reading in the visual-only condition and showed less visual influence on the incongruent audiovisual tokens than did nonsubstituters. These results support our hypothesis that experience correctly producing consonants plays a role in the elaboration of the underlying representation.