Children whose mothers were more nurturing during the preschool years, rather than later on in childhood, have better growth in brain structures associated with learning memory and stress response than kids with less supportive mums.
As part of a study from Washington University School of Medicine, published in the Proceedings of National Academy of Sciences, 127 children underwent three magnetic resonance imaging (MRI) brain scans beginning in the preschool period and including three scans through school age and early adolescence.
Analysing the results, the researchers observed a sharper rise in the volume of the hippocampus in children whose mothers supported and nurtured them as preschoolers. Why is hippocampal growth significant? The hippocampus is a part of the brain that's critical for learning, memory and regulating emotions.
The research team also discovered that, even if mums who were less nurturing in the preschool years became more supportive as their children got older, the hippocampus in these adolescents still appeared smaller. What exactly does this mean? In simple terms, the interactions we have with our kids in those early years really do matter when it comes to our children's brain development.
Reflecting on the findings, lead author and psychiatrist Dr Joan Luby said in a statement, "The study suggests there's a sensitive period when the brain responds more to maternal support ... The parent-child relationship during the preschool period is vital, even more important than when the child gets older."
Luby explained that they think this is due to greater plasticity in the brain when kids are younger, "meaning that the brain is affected more by experiences very early in life".
So how exactly do you measure "nurturing"?
"The mother is asked to complete a task while we give the child an attractive gift to open, but we don't allow it to be opened right away," Luby explains. "It's a stressful condition like those that happen multiple times each day in any given family, like when you're cooking dinner and a child wants attention. The child needs something, but you have something else to do, so it challenges your parenting skills."
The interactions between the mothers and their children were videotaped and scored. Parents who completed the tasks and were still able to offer emotional support to their kids were deemed more supportive and nurturing. In contrast, mums who dismissed their kids or behaved in more "punitive ways" during the interaction, received lower marks.
According to Luby, "Children whose mothers were more supportive than average had increases in growth of the hippocampus that were more than two times greater than in those whose mothers were slightly below average on the nurturing scale."
Yet another key finding: hippocampal growth was also linked to healthier emotional functioning when the children became teenagers.
The results have important implications.
"Early maternal support affects the child's brain development," Luby explained. "We also know that providing support to parents can have a positive impact on other behavioural and adaptive outcomes in children. So we have a very logical reason to encourage policies that help parents become more supportive."
So, to the frazzled mothers of preschoolers doing their best to keep calm and carry on amidst the chaos – hang in there. Your patience, and support is making a big difference to your little one's brain.