Weighting of static and transition cues in voiceless fricatives and stops in children wearing cochlear implants

To determine how normal-hearing adults (NHA), normal-hearing children (NHC) and children wearing cochlear implants (CI) differ in the perceptual weight given cues for fricative consonants (having a comparatively long static cue and short transition cue) versus stop consonants (having a comparatively short static cue and long transition cue).

Ten NHA, eleven 5- to 8-year-old NHC and eight 5- to 8-year-old children wearing CI were participated. Fricative /su/-/∫u/ and stop /pu/-/tu/continua were constructed by varying the fricative/burst cue and the F2 onset transition cue. A quantitative method of analysis (analysis of variance model) was used to determine cue weighting and measure cue interaction within groups.

For the fricative consonant, all groups gave more weight to the frication spectral cue than to the formant transition. For the voiceless stop consonant, all groups gave more weight to the transition cue than to the burst cue. The CI group showed similar cue weighting strategies to age-matched NHC, but integration of cues by the CI group was not significant.

All groups favored the longer-duration cue in both continua to make phonemic judgments. Additionally, developmental patterns across groups were evident. Results of the current study may be used to guide development of CI devices and in efforts to improve speech and language of children wearing CIs.