Examining micro-level natural behaviour to improve generalizability in behavioural science: a case study of parent–child joint attention

One of the primary aims of cognitive and behavioural sciences is to generate empirical findings that are both reproducible and generalizable to real-world settings. The present study investigates the extent to which results obtained from a structured laboratory task-parent-infant toy play-can be generalized to more naturalistic contexts and everyday activities. We focused on joint attention between parents and infants, a construct that has been extensively examined within developmental science. To characterize parent-infant joint attention during toy play, we recorded and analysed contingent gaze behaviour captured through dual head-mounted eye-tracking devices worn simultaneously by parents and their infants during spontaneous activities such as toy play and meal preparation. By continuously monitoring gaze locations and manual actions, we obtained fine-grained measures of how often dyads fixated on the same object concurrently and how their coordinated visual and manual behaviours contributed to the establishment and maintenance of joint attention. Our results suggest that laboratory findings can be both replicated and generalized when: (i) the study is designed to capture natural behaviours rather than to elicit specific, constrained responses, and (ii) the theoretical constructs are clearly defined and precisely measured through high-resolution behavioural data. This article is part of the theme issue 'Mechanisms of learning from social interaction'.