Maternal scaffolding modulates 4- to 6-year-olds’ brain activity in real time during collaboration

For fifty years, developmental scientists have theorised that children’s cognitive development is supported by the help, or scaffolding, they receive when faced with a difficult task. The rationale is that that by reducing the cognitive load on the child, scaffolding allows children to practice cognitive skills required to eventually complete challenging tasks on their own. To test this neural explanation directly, this study investigated whether maternal scaffolding modulated young children’s brain activity in real-time during naturalistic collaborative problem-solving. A multimodal cross-brain generalised linear model (GLM) was used to model children’s brain activity over time as a function of maternal scaffolding and mothers’ own brain activity. Results revealed maternal scaffolding up-regulated haemodynamic activity in children’s prefrontal cortices (PFC) bilaterally. In addition to scaffolding effects, mothers’ right PFC signal statistically predicted unique variance in children’s right PFC activity. These results are the first to suggest that parents’ interactive behaviours affect moment-to-moment changes in children’s functional brain activity during unstructured interactions. They also indicate separable neural and behavioural impacts of the parent on children’s right prefrontal activity in a collaborative context. Implications for interpreting two-person developmental neuroscience with multimodal data integration are discussed.