Beyond social facilitation and inhibition: Experimenter presence regulates executive function engagement in children

Executive function (EF) performance, which is often treated as an index of children's endogenous self-regulatory capacity, is assumed to be independent of immediate context. However, EF is typically assessed in the presence of an experimenter, and little is known about how this presence shapes performance. We examined the developmental trajectory of experimenter presence effects on children's EF and their modulation by working memory demands. French children aged 4-8 years (N = 54, 17 boys, 37 girls, majority White and upper-middle SES) completed a Go/no-Go task in which working memory load was orthogonally manipulated, both in the presence and absence of the experimenter. Children were slower and made fewer errors when the experimenter was present. Exploratory order analyses showed that these effects were stronger when the experimenter presence condition was completed first, particularly among younger children. Subsequent drift diffusion modeling indicated that the order-dependent effects of experimenter presence were associated with increased nondecision time, with modest evidence and little evidence for changes in evidence accumulation and response caution, respectively. Together, these findings demonstrate that children's EF performance in a canonical task is shaped by their immediate social context.