This study was designed to provide a general picture of infant vocal -motor coordination and test predictions generated by Iverson and Thelen's (1999) model of the development of the gesture -speech system. Forty-seven 6-to 9-month-old infants were videotaped with a primary caregiver during rattle and toy play. Results indicated an age-related increase in frequency of vocal -motor coordination, greater coordination with arm (specifically right arm) than leg or torso movements, and a temporal pattern similar to that in adult gesture -speech coproductions. Rhythmic vocalizations (consonant -vowel repetitions) were more likely to occur with than without rhythmic movement, and with rhythmic manual than with nonmanual activity, and the rate of vocalmanual coordination was higher in babblers than in prebabblers.

The performance of deaf children with cochlear implants was assessed using measures standardized on hearing children. To investigate nonverbal cognitive and sensorimotor processes associated with postimplant variability, five selected sensorimotor and visuospatial subtests from A Developmental Neuropsychological Assessment (NEPSY) were compared with standardized vocabulary, reading, and digit span measures. Participants were 26 deaf children, ages 6-14 years, who received a cochlear implant between ages 1 and 6 years; duration of implant use ranged from 3 to 11 years. Results indicated significant correlations between standard scores on the Design Copying subtest of the NEPSY and standard scores on vocabulary comprehension, reading, and digit span measures. The results contribute to our understanding of the benefits of cochlear implantation and cognitive processes that may support postimplant language and academic functioning.

This study investigated receptive vocabulary delay in deaf children with cochlear implants. Participants were 23 children with profound hearing loss, ages 6-14 years, who received a cochlear implant between ages 1.4 and 6 years. Duration of cochlear implant use ranged from 3.7 to 11.8 years. Peabody Picture Vocabulary Test, Third Edition (PPVT-III) data were analyzed first by examining children's errors for evidence of difficulty in specific lexical content areas, and second by calculating standard scores with reference to hearing age (HA) (i.e., chronological age [CA]--age at implantation) rather than CA. Participants showed evidence of vocabulary understanding across all PPVT-III content categories with no strong evidence of disproportionate numbers of errors in any specific content area despite below-average mean standard scores. However, whereas mean standard scores were below the test mean established for hearing children when based on CA, they were within the average range for hearing children when calculated based on HA. Thus, children's vocabulary knowledge was commensurate with years of cochlear implant experience, providing support for the role of spoken language experience in vocabulary acquisition.

This study investigated effects of profound hearing loss on mother-infant interactions before and after cochlear implantation with a focus on maternal synchrony, complexity, and directiveness. Participants included two groups of mother-infant dyads: 9 dyads of mothers and infants with normal hearing; and 9 dyads of hearing mothers and infants with profound hearing loss. Dyads were observed at two time points: Time 1, scheduled to occur before cochlear implantation for infants with profound hearing loss (mean age = 13.6 months); and Time 2 (mean age = 23.3 months), scheduled to occur approximately six months after cochlear implantation. Hearing infants were age-matched to infants with hearing loss at both time points. Dependent variables included the proportion of maternal utterances that overlapped infant vocalizations, maternal mean length of utterance, infant word use, and combined maternal directives and prohibitions. Results showed mothers’ utterances overlapped the vocalizations of infants with hearing loss more often before cochlear implantation than after, mothers used less complex utterances with infants with cochlear implants compared to hearing peers (Time 2), and mothers of infants with profound hearing loss used frequent directives and prohibitions both before and after cochlear implantation. Together, mothers and infants adapted relatively quickly to infants’ access to cochlear implants, showing improved interactional synchrony, increased infant word use, and levels of maternal language complexity compatible with infants’ word use, all within seven months of cochlear implant activation.