New Hope for Children at Risk for Antisocial Behavior: Cortisol Stress Levels Studied

Family-Based Interventions Can Lead to More Typical Stress Responses

Researchers have known for some time that the level of the hormone cortisol rises in preschoolers when presented with social stresses such as joining unfamiliar peer groups. Cortisol rises in normally developing children in socially challenging situations but it remains puzzlingly low in children who develop antisocial behaviors. This atypical cortisol response is consistent with other patterns of response in delinquent youth, such as difficulty interpreting social cues and being less responsive to social reinforcement. Cortisol is readily measured from saliva samples, making it a useful measure of stress in young children. It also sheds light on how early experiences and early intervention affect neurobiological systems.

Despite its obvious relevance, no randomized trials had been done examining changes in children's stress response to social challenges until New York University clinical psychologist Laurie Miller Brotman and colleagues took on the challenge.

Brotman, who led the study, says the findings have a number of implications. "They show that behavior is not 'hard-wired' into children but can be altered by effective interventions," she says. In this and previous work, she has found that important changes in parenting and child behavior can be made through effective family intervention delivered to high-risk children during the preschool period.

They identified 92 families with (a) a preschool-age child and (b) an older child who had been adjudicated in the courts for offenses indicative of antisocial behavior. Satisfied they had a sample of preschool children at risk of developing antisocial behavior, they randomly divided the sample into a treatment and a control group.

The treatment group received a family-based intervention in the form of an adapted version of the Incredible Years parent training program. It consisted of 22 weekly, 90-minute group sessions for parents and preschoolers, 30 minutes of guided parent-preschooler interactions at the end of each of the 22 sessions, a minimum of 10 biweekly home visits with additional home visits as needed during the 6- to 8-month period of intervention.

In the parent groups, group leaders used videotapes, group discussion and other techniques to teach appropriate strategies for parenting. Parents were encouraged to use non-harsh, consistent discipline and to use positive reinforcement and play interactions to promote social competence. In the preschool groups, group leaders taught children social skills, reinforced positive behaviors and provided consequences for negative behaviors. At the end of each session, group leaders encouraged parents to practice specific parenting skills and strategies during the 30-minute guided parent-preschooler interactions. Home visits by group leaders helped parents implement what they learned in the home settings. The control group did not receive the intervention.

During an assessment before and after the intervention, children were presented with a social challenge in the form of a visit to a nearby nursery school where children were required to join an unfamiliar peer group for 30 minutes of play. Before leaving for the school, each study child was told he or she was "going to a school to play with some other children" so that they were made aware of an impending stressful experience. Upon arrival, a saliva sample was taken. After 30 minutes of play, another saliva sample was taken.

When the saliva samples were tested to determine the level of cortisol prior to children's entry into the unfamiliar peer setting (that is, in anticipation of the social challenge), the pattern of findings was striking. Before the program, as a group, these high-risk children did not show the expected elevation in cortisol in anticipation of the social challenge. After the program, children from the intervention group showed higher cortisol levels in anticipation of the social challenge while those from the control group showed cortisol levels that remained low. The post-challenge cortisol levels of both groups were low and did not change with intervention. The challenge cortisol levels were compared to baseline values from samples taken at home under non-stressful conditions.

Taken together, these findings suggest that participation in a family-based prevention program has an effect on children's response to stress, as reflected in the levels of the hormone cortisol. Furthermore, this study provides evidence to suggest that early experiences, including non-pharmacologic interventions (such as programs to improve parenting and child behavior) early in childhood can have an impact on neurobiological systems in children.