UNIVERSITY PARK, Pa. — Parents in the midst of a psychologically or physically aggressive argument tend to also be aggressive with their children, according to researchers at Penn State. The team found that this "spillover" of aggression toward children causes kids to exhibit greater fear during future incidents of interparental aggression, regardless of the severity of those future incidents, than children who do not experience this spillover effect.

"Our study is the first to examine how aggression toward a child and aggression toward a parenting partner unfold at the same time," said Amy Marshall, associate professor of psychology.

The researchers also found that spillover-exposed children are more likely to engage in their parents' more severe aggressive conflicts by attempting to solve the problem or by making peace between their parents than non-spillover-exposed children.

"Our findings suggest that children may fear for their own safety because of their history of having had aggression directed toward them during incidents of interparental aggression," said Marshall. "Previously, researchers thought that kids reacted negatively to interparental violence because it threatened their security within the family unit. For example, it was assumed that children were afraid that their parents would divorce. This study shows that kids may also be afraid of what might happen directly to them."

The team conducted four interviews with 203 parents — 109 women and 94 men — from 111 heterosexual couples whose first-born child was 2 to 3 years old at the beginning of the study. The researchers used the responses to examine the occurrence, unfolding, and context of episodes of psychological and physical family aggression — both interparental and parent-child aggression. They defined aggression as non-playful behaviors that are threatening or forceful in nature. Physical aggression included behaviors such as pinching, slapping, hitting and kicking, whereas psychological aggression included behaviors such as insulting, screaming and threatening harm.

"Although our study sample represents families who are in a relatively high-stress developmental period during which aggression is especially likely to occur, it was otherwise a relatively low-risk sample," said Marshall. "The families were recruited originally to an intervention study focused on establishing stronger co-parenting relationships. On average, they represent relatively high-income, well-educated families."

The researchers administered the interviews by telephone, asking participants to work backward in time to review all incidents of interparental and parent-child aggression. For each aggressive incident, parents self-reported the type of aggressive behavior, the order of the behaviors, and the victim and perpetrator of each behavior. At the end of each interview, parents were provided individualized motivation, assistance and resources for preventing future acts of aggression.

Across all participants, the researchers selected 463 incidents of relatively more severe interparental aggression reported by 73 families. They found that children were present during 163 of these incidents. Of these 163 incidents, 40 included parent-child aggression. The results appear today (April 4) in the Journal of Family Psychology.

This was not the full extent of parent-child aggression recorded by the researchers, however. The team found that parent-child aggression occurred much more frequently on its own than it did in association with interparental aggression.

"We know that parents who perpetrate aggression toward each other are also very likely to perpetrate aggression toward their children," said Marshall. "But until now, we didn't know how that happens — if it happens on different days for different reasons, or if it happens at the same point in time. This is the first study to look at how those two types of aggression happen at the same point in time."

According to Mark Feinberg, research professor of health and human development with the Edna Bennett Pierce Prevention Research Center, the findings can be used to plan future studies examining family aggression in higher risk samples and ultimately to develop preventive interventions to address family profiles of aggression.

"Our existing public health programs so far are not very good at preventing the occurrence of family violence, which is more widespread in society than we usually assume," said Feinberg. "One reason is that, until now, we have had no way of examining how these aggressive incidents unfold. With this new interview method, we can unpack the different ways aggressive incidents play out, and develop tailored approaches for different patterns of aggression."

Kelly Daly, graduate student in psychology, also is an author on the paper.

The National Institute of Child Health and Human Development supported this research.