ManyBabies1: Infants' preference for infant-directed speech

Abstract

There is growing concern about the replicability of basic findings in psychology, including in infancy research (Frank et al., 2017). ManyBabies is a large-scale international collaboration to replicate basic empirical findings in infancy. Our first project is ManyBabies1, which examines infant preference for infant-directed speech (IDS). Over 70 laboratories collaborated to collect data from over 2500 infants aged 3–15 months. Stimuli consisted of speech produced in a semi-naturalistic elicitation task where fifteen different mothers who spoke North American English talked about a series of novel and familiar objects to their infant and separately to an experimenter. A set of 8 passages each in IDS and adult-directed speech (ADS) were created after a comprehensive norming process. Infants were tested in 3 primary methods: eyetracking, central fixation and headturn preference. Overall, the effect of preference for IDS was replicated, although the calculated effect was smaller than that reported by meta-analysis (Dunst et al., 2012, metalab.stanford.edu). Preference for IDS increased across development. The success of this project shows that infant research conducted collaboratively and at-scale can answer new questions about the replicability and generalizability of infant findings across different laboratory, methodological, and infant participant characteristics.