The Effects of Early Acoustic Hearing for Pediatric Cochlear Implant Recipients

PROJECT SUMMARY/ABSTRACT For children with hearing loss (HL), speech perception assessments are fundamental to guiding all aspects of habilitation including device candidacy, validation, and therapy goals. Good speech perception requires not only identifying individual vowel and consonant sounds (segmental) but also perceiving prosodic aspects of speech such as intonation, stress and rhythm (suprasegmental). The role of segmental perception for development of spoken language and reading is firmly established for children with typical hearing (TH). The complementary role of suprasegmental perception for spoken language acquisition and, more recently, for reading development has also been established for children with TH. Even though suprasegmental speech perception contributes essential information to listeners with TH, it has been largely neglected in studies of speech perception for individuals with HL. Given the known significant role that suprasegmental perception has for critically important spoken language and reading skills of children with TH, and the unknown suprasegmental perception abilities of children with mild to profound HL, we seek to understand the manners in which both segmental and suprasegmental perception develop in such children. For children with two HAs and with a continuum of HL, we seek to determine the hearing threshold level (dB HL) above which better results are more likely to be obtained through either bilateral or bimodal cochlear implantation. The motivation for extending studies to children with greater levels of residual hearing is due to changing clinical protocols that now include children with thresholds as low as 60-70 dB HL for CI candidacy, and which stress early receipt of bilateral CIs. A logical question, and one that is not addressed explicitly in these recommendations, is: should children with more residual hearing stay with 2 HAs, continue with 1 HA and receive 1 CI (bimodal), or receive 2 CIs? Specific Aim 1A: For children with mild to profound HL who use two devices, we will determine the contributions of acoustic experience (audibility and duration) to the development of suprasegmental and segmental perception. We predict that children with greater acoustic experience will develop suprasegmental skills that approach their TH peers. Specific Aim 1B: For children with mild to profound HL who use two devices, we will determine the contributions of auditory capacity (select suprathreshold abilities) to the development of suprasegmental and segmental perception. Specific Aim 2: We will assess the risk-benefit associated with CI- and/or HA-use by establishing audibility ranges for which children with 2 HAs perform better on suprasegmental and segmental perception than children with 2 CIs or bimodal devices. Specific Aim 3: We will quantify the relative contributions of suprasegmental and segmental perception to these same children's development of spoken language and reading skills.