Acoustic Properties of Infant-Directed Speech

Language acquisition is a complex process that involves an interaction between learning mechanisms and the input to the child. An important component of infants’ input is infant-directed speech (IDS)—a unique speech register that caregivers use when talking to infants. IDS differs from adult-directed speech (ADS) in a variety of dimensions. This chapter examines empirical research on the acoustic properties of IDS and the role that IDS may play in supporting infant language learning. Taking the discussion of IDS function in language development to the next level, this chapter further discusses the underlying mechanisms of IDS to promote language learning and caregivers’ intentions to use this speech register. Theoretical and practical implications of this body of work are discussed and areas for future research are highlighted.