Objectives: With the application of universal newborn hearing screening programs, a large pool of newly identified deaf infants has been identified. The benefits of early intervention with cochlear implants (CI) is being explored. Mounting evidence suggests that age at implantation is a strong predictor of language outcomes. However, new behavioral procedures are needed to measure speech and language skills during infancy. Also, procedures are needed to analyze the speech input to young CI recipients.
Study Design: Cohort-sequential.
Methods: Thirteen infants with profound hearing loss who were implanted between the ages of 6 to 12 months of age participated in this study. Eight participated in two new behavioral methodologies: 1) the visual habituation procedure to assess their discrimination of speech sounds; 2) the preferential looking paradigm to assess their ability to learn associations between speech sounds and objects. Older implanted infants and normal-hearing infants were also tested for comparison. The pitch of mothers' speech to infants was analyzed.
Results: Patterns of looking times for the very early implanted infants were similar to those of normal hearing infants. Mothers' speech to infants with CIs was similar in pitch to normal-hearing infants who had the same duration of experience with sounds.
Conclusions: No surgical or anesthetic complications occurred in this group of infants, and the pattern of listening skill development mirrors that seen in normal-hearing infants. Mothers adjust their speech to suit the listening experience of their infants.