Experience-sensitive effects on temporal profiles of social attention in early childhood

A bilingual’s highly variable early language learning demands may drive adaptations in social attention. For example, bilinguals show differences in face processing compared to monolinguals, automatically orienting more rapidly to faces and dwelling longer on faces and mouths than monolinguals. However, it is difficult to identify specific visual strategies from average-level data. This pre-registered study uses growth curve analysis within trials to explore individual differences in monolingual and bilingual children’s dynamic allocation of visual attention to faces and mouths in two age groups: seven- to 18-month-olds (n = 131 infants) and 18- to 34-month-olds (n = 745 toddlers). Results show that children’s attentional trajectories for viewing static faces and dynamic mouths is sensitive both to age and to children’s early language environments. Specifically, young bilinguals showed stronger systematic disengagement than monolinguals from faces and mouths after initial orientation. In contrast, older bilinguals prioritised the mouth more than monolinguals overall, driven by their steeper gradual increase in mouth-looking over stimulus time. Age-dependent shifts in attentional allocation over stimulus time were also evident, particularly in viewing of static faces. In infants, younger children showed earlier re-fixations to static faces than older children. In toddlers, attention to faces was more stable over stimulus time in older than younger children. Overall, the results suggest that age modulates the temporal structure of all children’s social attention from seven- to 34-months of age and are consistent with the hypothesis that bilinguals develop adaptive visual strategies to maximise their processing of social information.