Emergent tool use in infancy: Insights from natural observations

Abstract

Despite being a foundational aspect of human cognition and development, tool use has rarely been studied in natural contexts, and fundamental questions about the natural input leading to early tool use remain unanswered. To address this gap, we conducted cross-sectional, natural observations of 30 infants (10 infants at 12, 18, and 24 months of age), recording one hour of unstructured play in their homes. Through detailed video annotation of infants’ hand behaviors, we examined and characterized the qualitative differences that can be observed in infants’ interactions with objects at these three time points in development. We captured evidence of a progression from simple object interaction among 12-month-olds to more sophisticated, goal-directed tool use among 24-month-olds. We also found that, while 12- and 18-month-olds engage in some tool use behaviors at home, most of the tool use occurred among 24-month-olds. This pattern of object interactions is consistent with the hypothesis that coordinated, goal-directed actions develop from accumulated knowledge from early object exploration and further suggests that the emergence of tool use in infancy is likely dependent on dynamic, interconnected systems of development rather than the result of a discrete, stage-like process. These findings underscore the potential importance of spontaneous, infant-driven play as a foundation for later tool use, and highlight that complex, goal-directed object actions develop from natural experiences enriched with opportunities for play and exploration.