Abstract
PURPOSE: The main purpose of this investigation was to examine the effects of cochlear implant experience on prelinguistic vocal development in young deaf children. Procedure A prospective longitudinal research design was used to document the sequence and time course of vocal development in 7 children who were implanted between 10 and 36 months of age. Speech samples were collected twice before implant activation and on a monthly basis thereafter for up to 2 years. Children's vocalizations were classified according to the levels of the Stark Assessment of Early Vocal Development--Revised (SAEVD-R; S. Nathani, D. J Ertmer, & R. E. Stark, 2006). RESULTS: The main findings were (a) 6 of 7 children made advancements in vocal development after implantation; (b) children implanted between 12 and 36 months progressed through SAEVD-R levels in the predicted sequence, whereas a child implanted at a younger age showed a different sequence; (c) milestones in vocal development were often achieved with fewer months of hearing experience than observed in typically developing infants and appeared to be influenced by age at implantation; and (d) in general, children implanted at younger ages completed vocal development at younger chronological ages than those implanted later in life. Specific indicators of benefit from implant use were also identified. CONCLUSION: The time course of vocal development in young cochlear implant recipients can provide clinically useful information for assessing the benefits of implant experience. Studies of postimplantation vocal development have the potential to inform theories of spoken language development.