Mothers' speech to hearing-impaired infants and children with cochlear implants

This study investigated the effects of age, hearing loss, and cochlear implantation on mothers' speech to infants and children. We recorded normal-hearing (NH) mothers speaking to their children as they typically would do at home and speaking to an adult experimenter. Nine infants (10-37 months) were hearing-impaired and had used a cochlear implant (CI) for 3 to 18 months. Eighteen NH infants and children were matched either by chronological age (10-37 months) or hearing experience (3-18 months) to the CI children. Prosodic characteristics such as fundamental frequency, utterance duration, and pause duration were measured across utterances in the speech samples. The results revealed that mothers use a typical infant-directed speech style when speaking to hearing-impaired children with CIs. The results also suggested that NH mothers speak with more similar vocal styles to NH children and hearing-impaired children with Cls when matched by hearing experience rather than chronological age. Thus, mothers are sensitive to hearing experience and linguistic abilities of their NH children as well as hearing-impaired children with Cls.