Clues to young children's aggressive behavior uncovered by new study

The study was done by researchers at the University of Minnesota and appears in the journal Child Development.

The researchers looked at more than 260 mothers and their children, following them from the children's birth until first grade. They assessed infants' difficult temperament as well as how they were parented between the first week and the sixth month of life, based on both observations and parent reports. When the children were 2 and a half and 3 years old, the researchers watched mothers with their children doing tasks that challenged the children and required assistance from the parents. Finally, when the children were in kindergarten and first grade, researchers asked moms and teachers to rate the children's behavior problems.

"Before the study, we thought it was likely the combination of difficult infant temperament and negative parenting that put parent-child pairs most at risk for conflict in the toddler period, and then put the children at risk for conduct problems at school age," according to Michael F. Lorber, a research scientist at New York University and lead author of the paper (Lorber was previously at the University of Minnesota). "However, our findings suggest that it was negative parenting in early infancy that mattered most." Negative parenting occurred when parents expressed negative emotions toward their children, handled them roughly, and so forth.

The researchers also found that it was conflict between moms and their toddlers that predicted later conduct problems in the children -- and not just a high level of conflict, but conflict that worsened over time. And in a cyclical pattern, when moms parented their infants negatively, that resulted in their children showing high levels of anger as toddlers, which in turn caused more hostility from the moms.

By the same token, moms who parented their infants negatively also may have had angrier kids because these moms were more hostile toward their toddlers. Negative parenting in infancy appeared to set the stage for both moms and their kids being more hostile and angry during the toddler years, bringing out the worst in one another.

"The results of our study move beyond descriptive findings to explain the underlying process linking how mothers parent their children in infancy and the problems children have in early elementary school," Lorber adds.

The study's findings can inform the development of appropriate interventions that target negative parenting as early as 3 months to help prevent later conduct problems in children.

The study was supported by the National Institutes of Health.