Effects of familiar contingencies on infants' vocal behavior in new communicative contexts.

Recently, there has been a growing interest in understanding the mechanisms underlying vocal learning in songbirds and human infants. Research has demonstrated how contingent social feedback from social partners to immature vocalizations can play a role during vocal learning in both brown-headed cowbirds and prelinguistic infants. Contingencies in social interactions, particularly familiar contingencies, are important in developing preferences for social partners and shaping social exchanges Bigelow and Birch [1999]. Infant Behavior & Development 22:367-382]; however, little is known about how familiar contingencies that individuals experience during communicative exchanges play a role in new contexts. The current study examined differences in caregiver response patterns to infant vocal behavior and assessed how familiar contingencies influenced infant vocal behavior in novel communicative exchanges with caregivers. Infants were systematically exposed to high and low social feedback schedules during a play session. Results revealed the frequency of caregiver responsiveness to which infants were accustomed to affected infant vocal production during novel communicative situations. Infants with high responding caregivers vocalized with more mature vocalizations and used their vocalizations differently than infants with low responding caregivers during the high, but not low, response period. Specifically, infants with high responding caregivers directed more of their vocalizations at their caregiver and looked more at their caregiver after vocalizing, an indication of anticipating contingent responding. These results suggest that infants with high responding caregivers learned the association between vocalizing and contingent responses during the novel communicative interaction. This study demonstrates the need to understand how infants who experience a variety of contingencies in everyday interactions with caregivers carry over to other interactive situations.