Rhythmic Structure in Infant-Directed Communication

Infant-directed communication has been proposed to facilitate early language development, not only by providing infants with ample native language input but also by tailoring this input to infants’ individual developmental needs. In particular, extensive research has investigated prosodic and phonetic adaptations in caregivers’ infant-directed speech proposed to support early language acquisition, but more recently, research focus has shifted to the rhythmical properties of this register. This chapter will review this recent evidence, and it will argue that rhythmic optimization is not limited to infants’ early speech input. Instead, it is present across the auditory, visual, and tactile domains of caregiver-infant communication. We will argue that infants enjoy access to optimized intersensory rhythmic input, which scaffolds their ability to segment the continuous speech signal into meaningful linguistic units, even when these units occur with weak regularity in naturally produced adult-directed speech.