(New Orleans)-A University of New Orleans researcher studying violence and aggression has found that "impulsive aggressive" individuals--the so-called "short fuse" type differ biologically from others. Even more, the researchers suggests Dilantin, the anti-convulsant drug used to treat epilepsy, helps with the treatment. Another university researcher studying girls says puberty serves as a triggering mechanism in anti-social adolescent girls.

Murder. Rape. Aggravated assault. There are varying views on the origin, causes, prevention, and treatment of violence and aggression. Researchers from different disciplines subscribe to explanations that extend from biological and individual focused theories to broader sociological perspectives and community action.

University of New Orleans researchers offer their perspectives regarding the complex issue. Neuroscientist Dr. Matthew Stanford has found that "impulsive-aggressive" individuals--the so-called "short fuse" type of violent individuals--differ biologically from others. "Impulsive-aggressive individuals show cognitive, personality, and physiological differences," notes Stanford.

The primary issue, Stanford suggests, appears to be that impulsive-aggressive individuals have difficulty modulating the arousal of their cerebral cortex (the part of the brain involved in the highest levels of reasoning, planning, and behavioral control). When an impulsive-aggressive individual is sitting quietly, his/her cortex is underactive. "They can't process information as effectively," Stanford explains. "To compensate, they seek stimulation . . . and any entering stimulus then shoots their arousal level 'through the roof'." The result often manifests itself as an outburst of aggression.

Dilantin is old stand-by anti-convulsant drug used to treat epilepsy. Stanford and his collaborator Dr. Ernest Barratt, University of Texas Medical Branch in Galveston (who serve as the only people in the world conducting controlled studies of Dilantin on aggression) have found a new use for it--to help treat impulsive (or explosive) aggression. "Treatment with Dilantin significantly reduces both the frequency and intensity of aggressive outbursts," notes Stanford.

Now in his second year of a controlled study sponsored by the Dreyfus Health Foundation (an organization that funds research on Dilantin for non-epileptic uses), Stanford is optimistic about Dilantin's future in this new arena. It reduces anxiety, depression, and anger, and gives his clients the time to think before they act. Dilantin appears to work by helping the brain better modulate cortical arousal, according to Stanford. He continues, "This allows the individuals to process information more efficiently and have better control over their behavior."

Problems of Childhood Aggression

Dr. Paul Frick (Ph.D., University of Georgia) sees the problem of aggression in children as an important issue to research. "There are many different pathways kids follow in developing violent and aggressive behavior," he notes. Left undiagnosed and untreated, aggression in young children "shows up again and again" throughout adolescence and adulthood.

Frick, Director of the Applied Development Program at UNO, has identified several behavioral traits that predict different patterns of violent behavior. Not only does he divide his subjects into childhood-onset and adolescent-onset groups, as most of the profession does, he further divides the childhood group into impulsive and callous-unemotional subtypes.

"The impulsive group (about two-thirds of the childhood group) acts without thinking," Frick explains. "They feel bad about what they are doing, but they have trouble controlling their impulses. The other one-third, however, consists of individuals I call callous/unemotional (CU). They don't feel bad about their behavior. They lack guilt and empathy."

The subtypes show important differences that may require assorted intervention approaches. Dr. Thomas H. Ollendick, from the Child Study Center at Virginia Polytechnic Institute and State University agrees: "Subtyping of childhood aggression is critical from both a prevention and an intervention standpoint. Too frequently, our intervention efforts have been unsuccessful--largely because we have tried the same intervention (or prevention) program as if--one size fits all.' Frick's work points to the need to understand the type of aggression that we are attempting to treat."

For example, children in the adolescent-onset subtype, according to Frick, may require a different approach to intervention (e.g., developing adaptive ways of becoming independent of parents) compared to other aggressive children because the causes of their behavior are different. Similarly, he contends, the children in the childhood-onset subgroup who do not show CU traits may require another approach (e.g., helping parents develop better socialization strategies, and teaching children impulse control strategies, and social problem-solving strategies). And those with CU traits may require yet another approach, such as intervention focusing on empathy training, or intervention that capitalizes on their strong self interest. "Unfortunately, current treatments rarely attempt to 'individualize' their focus to those different processes," says Frick.

Frick's strategies arise out of his broad approach to understanding abnormal childhood behaviors. He studies not only violence and aggression, but other types of childhood disorders as well such as anxiety and depression. This developmental psychopathology focus integrates research on normal development with research on "disordered" development, he notes. "It's different from traditional clinical psychology that views abnormal behavior in isolation to normal behavior, and without understanding normal developmental processes as well." What different results is he getting? He's identified a different developmental pathway, added a complex layer to the research in his field, and proposed new interventions and treatments for this specific pathway.

Ollendick added, "This (Frick's) work is methodologically sound, conceptually savvy, and socially important! It needs to be done and Professor Frick is the right person to be doing it."

Frick recently completed the third year of a five-year, $1.5 million National Institute of Mental Health grant studying the pathways to violence, aggression, and conduct disorder of 1100 volunteer students in the public school system of Tuscaloosa, Alabama. In this study, Frick is following a group of students who he believes "display the traits" that place them at high risk for violent and aggressive behaviors. He hopes to use this research to determine how early he can identify those high risk children, and to determine what factors may keep these children from developing aggressive behaviors. "Those results should have some very direct implications for designing more effective prevention programs," he stated.

Different Pathway to Anti-social Behavior in Girls

In another area of study, clinical child psychologist Dr. Persephanie Silverthorn, roughly one of a dozen psychologists in the nation whose research focuses primarily on violence and aggression in girls ages 12 to 18, suggests that puberty serves as a triggering mechanism for anti-social, adolescent girls.

While boys may begin to manifest anti-social behavior in either childhood or adolescence, girls do not generally develop dangerous anti-social behaviors until puberty, Silverthorn suggests. She adds, "The significant changes in girls' biological and social milieu, in concert with the generally difficult transition to adolescence, and a marked decrease in self-esteem, can lead at this stage to violent and aggressive behavior in girls at risk. Girls follow a single development trajectory for anti-social behavior and/or violence." She calls it the "delayed-onset" pathway--one akin to Frick's childhood onset pathway in boys, but with a later onset.

---University of New Orleans

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