Children respond to environmental pressures, demands and adversity in varying ways. Some children direct their emotional problems outward into externalizing behaviors 4. These children express their negative responses to their life experiences by embarking on negative, often destructive action within or against the social and physical environment. As noted in the "Journal of Child and Adolescent Psychiatric Nursing," externalizing behavior can be contrasted to internalizing behavior, in which children direct their emotions and feelings into depressive, anxious or other inner-directed states 1.

Types of Externalizing Behavior

Typically, children who externalize enact their emotional issues by directing anger, frustration, anxiety or other emotions into aggressive or delinquent behavior. Hyperactivity and impulsivity are also classified as types of externalizing behavior.


Children who engage in externalizing behavior usually fall into specific diagnostic categories of the American Psychiatric Association’s "Diagnostic and Statistical Manual of Mental Disorders," or DSM -IV 2. Children who display aggressive behavior often are diagnosed with oppositional defiant disorder, while children who engage in delinquent behaviors tend to be diagnosed with conduct disorder. Children who are hyperactive, distracted and impulsive are often diagnosed with attention deficit hyperactivity syndrome.


Externalizing behavior has the immediate impact of disrupting the family, school or other social environment in which the child is acting out. Often, parents, teachers or other adults reprimand, punish or isolate the child. The potential long-term effects of unmitigated externalizing behavior are serious for the individual and for society. In 1996 close to 3 million juveniles were arrested. Children who engage in externalizing behavior are at greater risk for juvenile delinquency, violence and adult criminal behavior.

Early Biological Factors

Genetic and early maternal and environmental factors may contribute to the risk of externalizing behavior 4. Maternal malnutrition, smoking, drug and alcohol use during pregnancy, illness during pregnancy and birth complications may influence development and thereby contribute to the risk of externalizing behaviors. 1"

Typical Course

Most children display externalizing behavior, but as their nervous system, cognitive development and verbal abilities advance, their use of externalizing behavior peaks—usually in toddlerhood. By the time they enter school, externalizing behaviors have declined and are usually well managed. Children who fail to outgrow their externalizing behavior tendencies follow different courses, sometimes leading to delinquent or aggressive behavior patterns that extend into adulthood.

Later Social Risk Factors

Other risk factors include drug or alcohol abuse and poor cognitive ability 1.


Interventions for externalizing behavior include pharmacologic treatment, using medications such as lithium, resperidone, methylphenidate and haloperidol. Behavior management and parenting effectiveness programs assist children and families to manage externalizing behaviors.