Child-produced speech preferences in 9-14-month-old infants with and without older siblings [working paper]

Infants learn language through their linguistic experiences, but most of this research has focused on what infants hear from adult caregivers. However, children do not exclusively interact with adults. In the US and around the world, children spend time with other children, and hear speech from these other children. Child-produced speech shares properties with infant-directed speech produced by adults (higher in pitch and slower in duration), and research suggests that infants preferentially attend to adult-produced infant-directed speech. We tested whether 9-11-month old and 12-14-month-old infants with and without older siblings prefer to listen to adult infant-directed-speech or child-produced speech. Results suggest that infants, regardless of prior experience, attend to child-produced speech as much as adult-produced speech, and that younger infants with older siblings prefer listening to child-directed speech. Results are discussed as they relate to the types of speech we should consider in our theories of language development.