Aggressive behavior among adolescents has become a major public health problem (Human Capital Incentive, 1997; Centers for Disease Control, 2001). Despite the recent reduction in youth violence and homicide rates occurring after 1994, these rates are still high (Brener, Simon, Krug, & Lowry, 1999; Centers for Disease Control, 2001; Federal Bureau of Investigation, 2000, 2001). For example, the incidence of arrests for violent offenses for boys younger than 18 is disproportionately high (Federal Bureau of Investigation, 2000, 2001) and homicide has become a leading cause of death for adolescents (Anderson, Kochanek & Murphy, 1997; Centers for Disease Control, 2001; Federal Bureau of Investigation, 2000). Aggression, which can be defined as "destructive behavior with intent to inflict harm or physical damage" (Marwick, 1996, p. 90), remains one of the most difficult problems to study and treat in adolescents (Malone, Luebbert, Pena-Ariet, Biesecker, & Delaney, 1994).
DSM-IV does not classify adolescent aggression as a separate disorder; rather, it is a major characteristic in a number of Axis I and II disorders, such as conduct disorder and antisocial personality (American Psychiatric Association, 1994). Research on aggression has revealed that the major type of aggression is characterized by high levels of arousal and poor modulation of behavior (Vitiello, Behar, Hunt, Stoff, & Ricciuti, 1990; Vitiello & Stoff, 1997). This type of aggression is mostly a defensive fight-or-flight response to a perceived threat.
Aggression has been associated with both high levels of arousal and underarousal, suggesting that aggressive behavior may arise from distinct biopsychosocial pathways in different individuals (Scarpa & Raine, 1997; Raine, 1996). The lack of a generally accepted treatment for aggression (Malone et al., 1994) may be explained by the different mechanisms underlying each of these two types of aggression (Vitie-llo & Stoff, 1997). These different aggressive styles complicate the assessment and treatment of aggression due to their distinct mechanisms of action.
As with some mood disorders, aggression has also been characterized by impulsivity, hostility, anger, and fear (Atkins & Stoff, 1993; Scarpa & Raine, 1997; Vitiello & Stoff, 1997). Mood disturbances including anxiety and depression have been associated with aggression (Botsis et al., 1997; van Praag, 2001), and research on aggressive behavior in children and adolescents indicates that anxiety may help predict the type of aggression being displayed. For example, while bullies show overt aggressive behavior marked by low levels of anxiety and underarousal, victims show indirect aggression marked by high anxiety levels and arousal (Craig, 1998). The absence of physical affection or the presence of neglect and physical abuse may create emotional traumas that result in either heightened sensory thresholds leading to underresponsivity to stimulation (Orbach, Mikulincer, King, Cohen, & Stein, 1997) or altered neurological development leading to physiological overreactivity (Dodge, Bates, & Pettit, 1990). These imbal ances in environmental reactivity may lead to aggressive behaviors through increased arousal-seeking behaviors or oversensitivity to stimulation.
Due to the lack of effectiveness of any single behavioral or cognitive treatment for all types of aggression (stemming from the complex mechanisms underlying aggressive behavior) and the unpleasant side effects of psychotropic drugs, complementary therapies are being investigated, such as training in aikido (a martial art similar to karate or judo) as a means of reducing aggressiveness in youth (Delva, 1995). Studies on biofeedback (Braud, 1978) and relaxation training (Dangel, Deschner, & Rasp, 1989; McPhail & Chamove, 1989), for example, suggest that these therapies are effective in diminishing aggressive behavior. …