Strollers and backpacks are employed early, frequently and throughout the first year, with parents overwhelmingly using strollers. However, because these transport modalities put infants in different proximities to caregivers, postures, and states of alertness, their use may translate to different opportunities that are of developmental consequence, particularly with regard to language. We used GoPro technology in a within subjects counter-balanced design to measure dyadic vocalizations in strollers and backpacks with 7-to-11-month-old infants. Parent-infant dyads (N=36), who regularly used both transport modes took two 8-minute walks in their own neighborhoods using their own carriers while wearing lightweight head-mounted GoPros. There was significantly more parent speech, infant vocalizations, dyadic conversations and infant-initiated speech in backpacks, as well as more head motion consistent with visual scanning by infants. Backpacks appear to be a practical way to encourage more engaging, language-enriched developmental opportunities in the critical first year.
Keywords: Carrying; Infants; Language; Posture.