Role of visual speech in phonological processing by children with hearing loss

This research assessed the influence of visual speech on phonological processing by children with hearing loss (HL).

Children with HL and children with normal hearing (NH) named pictures while attempting to ignore auditory or audiovisual speech distractors whose onsets relative to the pictures were either congruent, conflicting in place of articulation, or conflicting in voicing-for example, the picture "pizza" coupled with the distractors "peach," "teacher," or "beast," respectively. Speed of picture naming was measured.

The conflicting conditions slowed naming, and phonological processing by children with HL displayed the age-related shift in sensitivity to visual speech seen in children with NH, although with developmental delay. Younger children with HL exhibited a disproportionately large influence of visual speech and a negligible influence of auditory speech, whereas older children with HL showed a robust influence of auditory speech with no benefit to performance from adding visual speech. The congruent conditions did not speed naming in children with HL, nor did the addition of visual speech influence performance. Unexpectedly, the /wedge/-vowel congruent distractors slowed naming in children with HL and decreased articulatory proficiency.

Results for the conflicting conditions are consistent with the hypothesis that speech representations in children with HL (a) are initially disproportionally structured in terms of visual speech and (b) become better specified with age in terms of auditorily encoded information.