Why is it that some children can overcome growing up in a stressful environment while others struggle? This is the question that researchers at Brown University's Brown Center for the Study of Children at Risk recently decided to study, with surprising methodology and results.
For the purposes of this study, the researchers specifically looked at children who were growing up in poverty. They brought in mothers and their babies and allowed the babies to watch a soothing video while they monitored each child's breathing and heartbeat. Sensors recorded how quickly each baby's heartbeat when the baby breathed in, and how quickly it beat when the baby breathed out. The difference between these two figures is a scientific term called baseline respiratory sinus arrhythmia that researchers have come to understand is directly associated to a baby's temperament and gives a good indication of how he responds to the world around him.
For example, babies for whom the difference in heartbeats is high, tend to have strong attention span and be good at concentrating on a toy or image for long periods of time. But they also tend to be more fussy and irritable — particularly when they meet unexpected changes to their day-to-day routine. Babies for whom the number is smaller are more mellow but they also don't have nearly as strong an attention span.
So babies who have a high number difference tend to be more sensitive to change, while babies with a lower number are less sensitive.
Interesting, but how can a baby's heartbeat rhythm affect her ability to overcome stress? That's where the maternal attachment comes in.
In the next phase of the study, researchers looked at the bond between the same mother/child pairs — only by this time the children were of toddler age at around 17 months. Toddlers who were easily soothed by their mothers after a stressful incident were rated as having a strong attachment while toddlers who could not be soothed were rated as having a lower attachment level to their mothers.
And here's where it gets really surprising.
Researchers found that a child's future behavior could be linked to how sensitive he is to his environment and how strong his attachment is with his mother. You might think that babies who were more sensitive to change would do poorly growing up in a stressful situation, but these children actually did the best and had the strongest chance of overcoming stress — in this instance poverty — as long as they also had a strong and stable bond with their mothers. On the other hand, the children with a high sensitivity who did not have a strong attachment had the lowest chances of overcoming their stressful childhood. Children with low sensitivity seemed unaffected by their attachment with their moms — some did well, some did poorly — but it was not related to their maternal bond.
Researchers hope that this data will give parents and caregivers a better understanding of a child's needs and sensitivities, right from birth.