Vocal turn-taking between mothers and their hearing-impaired infants with cochlear implants

Normal-hearing (NH) infants participate in social exchanges soon after birth. What does the temporal organization of vocal turn-taking (VTT) look like in infants with hearing loss with cochlear implants? This study examined VTT during spontaneous play in eight dyads of mothers and their hearing-impaired (HI) or age-matched NH infants (mean age 17.4 m at time 1). Dyads came to two sessions, corresponding to 3 and 12 months post-implantation. Analyses demonstrated that although HI infants vocalized less than NH infants, the proportion of vocalizations involved in VTT exceeded that from NH infants at time 1 and was equal at time 2. For vocalizations involved in VTT, there was a higher proportion of simultaneous speech in HI dyads compared to NH dyads at time 1, but the direction reversed at time 2. At time 1, the number of turns was greater in the HI group but decreased compared to the NH group at time 2. Duration of between-speaker pauses (BSP) was shorter in infant-mother compared to mother-infant turns in...