“What some kids can shrug off (could) be harmful to others” according to a 2007 study conducted by Daniel Hart, a psychologist at the Center for Children and Childhood Studies at Rutgers University (Camden, NJ) that found ties between certain nervous system responses and behavior problems in children.

Everyone’s bodies react differently to stress. Part of this reaction is inherited, and part is learned. Some kids’ autonomic reactions to stress are exaggerated, and Hart and his colleagues are concerned that kids with stronger physiological reactions to stress are at risk of developing an “under controlled” personality.

Autonomic reactions include heart rate, blood pressure, and digestion, and are not generally considered to be under a person’s direct conscious control.

While most kids can (and should) learn to deal with stress, the over-reacting kids were found to be more likely to have behavior problems like fighting with other kids. They were also likely to experience persistent negative emotions.

The findings of the six-year ongoing follow-up study of 138 children who were in kindergarten through 3rd grade when the study began suggest that these over-reacting kids may need to be shielded from chronic stress, such as the kind that occurs in dysfunctional households.

The risk for chronic stress seems to be greater in homes with lower incomes and less educated parents. The study found a correlation between over-reacting kids who lived in such homes, and reported behavior problems.

On the other hand, Hart and his colleagues discovered that over-reacting kids who lived in homes without chronic stress tended to do very well.

What does this mean for parents? If your child seems prone to over-reaction to stress, do your best to protect her from excess or chronic stress, especially in younger years. Once they learn to handle stressful situations with your help, they’ll need your protection less and less. This is one case where nurture can win out over nature with a little effort.