Prosodic modulation in the babble of cochlear implanted and normally hearing infants: a perceptual study using a visual analogue scale

This study investigates prosodic modulation in the spontaneous canonical babble of congenitally deaf infants with cochlear implants (CI) and normally hearing (NH) infants. Research has shown that the acoustic cues to prominence are less modulated in CI babble. However acoustic measurements of individual cues to prominence give incomplete information about prosodic modulation. In the present study, raters are asked to judge prominence since they simultaneously take into account all prosodic cues. Disyllabic utterances produced by CI and NH infants were presented to naive adult raters who had to indicate the degree and direction of prosodic modulation between syllables on a visual analogue scale. The results show that the babble of infants with CI is rated as having less prosodic modulation. Moreover, segmentally more variegated babble is rated as having more prosodic modulation. Raters do not perceive the babble to be predominantly trochaic, which indicates that the predominant stress pattern of Dutch is not yet apparent in the children’s productions

Mother-child interaction in two year old deaf and hearing children

The ten mother-child pairs in this investigation participate in a longitudinal study, from 2.5 to 24 months reported on before, in order to establish in which respect the sound productions of deaf children are influenced by lack of auditory perception. Previously, differences in vocalizations between deaf and hearing children were found with regard to number of spoken utterances and type of articulation and phonation. The missing auditory perception may seem the most obvious factor in explaining the differences, but various patterns in visual and vocal mother-infant-toddler interaction must not be neglected. Here we report on a verbal as well as a non-verbal evaluation of mother-child interaction at the age of two in five deaf and five hearing children. We used and adapted Kaye and Charney’s method (1980). A video recording was made in free play and instructed situations at home. This study focusses on verbal and non-verbal pragmatic aspects in mother-child interaction. It gives suggestions for further research with regard to the linguistic level of communicative turns.