The effects of an unfamiliar experimenter on proactive and reactive control in children.

Cognitive control development across childhood is critical for later academic achievement. Despite recent advances in the comprehension of how the context influences cognitive control development, no study has ever addressed whether one of the most frequent contextual features of children's lives (i.e., the presence of another person) impacts control engagement. Here, 123 Chinese children aged 5 and 9 years-old performed, either in the presence of an experimenter or alone, an AX-CPT, a task assessing reactive and proactive control. We found that children were overall negatively affected by the experimenter presence in terms of latencies but not of accuracy. Further, when analysing the trial types separately, we observed that this effect mainly concerned trials requiring children to engage more proactive control and was greater for younger than older children. These results indicate that direct social factors such as the presence of an unfamiliar experimenter seem to modulate cognitive control performance. Future research should continue to examine these effects in the light of the numerous existing social presence theories in order to unravel what are the cognitive mechanisms affected by social presence in childhood.