From Victim to Aggressor:

June 1, 2007

The traumatic events surrounding the recent school shootings at Virginia Tech remind us that a disturbing aspect of our current culture is the rate at which America's youth are exposed to violence. Whether it is graphic episodes of violence on television, violent music, aggressive video games, hearing about or witnessing violence in the home or neighborhood, or being the direct victim of violence--violence is a pervasive part of society that disproportionately affects youth.

The traumatic events surrounding the recent school shootings at Virginia Tech remind us that a disturbing aspect of our current culture is the rate at which America's youth are exposed to violence. Whether it is graphic episodes of violence on television, violent music, aggressive video games, hearing about or witnessing violence in the home or neighborhood, or being the direct victim of violence-violence is a pervasive part of society that disproportionately affects youth.1 In fact, between 3 and 10 million children annually witness acts of violence in their homes.2,3 Of these, about 60% have been victimized multiple times by physical or sexual abuse.4

Rates of child abuse and neglect in the United States range from 15 to 42 cases per 1000 children5,6 and of the 3 million cases of child abuse that are reported each year, 1 million are eventually substantiated.7 Similarly, as many as 60% to 70% of American youth have witnessed serious community violence,8-11 and homicide remains the second leading cause of death among youths aged 15 to 24 years.12 The fact that violence has become such a routine part of many children's lives raises serious concerns about the consequences of violence exposure. The issue of violence exposure and violence victimization has received considerable attention, and it is now regarded as a serious health problem affecting adolescents in nearly every sector of society.13

Cycle of violence

For decades, mental health professionals and social scientists have used the phrases "cycle of violence" and the "intergenerational transmission of violence" to describe the premise that "violence begets violence."14,15 Researchers have consistently found that children exposed to violence, either as witnesses or victims, are at high risk for having their own patterns of aggressive behavior develop. A considerable body of research points to a number of family, social, and community factors that increase the probability of violence. Specifically, family issues such as inadequate home environments,16 parental alcohol and drug abuse,17,18 witnessing domestic violence, and harsh parental discipline19 increase the risk for violent behavior in children and adolescents.

Children who are witnesses or the victims of community violence20-24 are also at increased risk for subsequent violent behavior. In addition, childhood maltreatment25,26 has a strong association with risk for violence. Childhood physical abuse in particular is thought to be one of the most frequent correlates of aggressive and delinquent behaviors in later life.27 For instance, in a large-scale prospective study using data taken 22 years after abuse or neglect, childhood abuse and neglect victims were significantly more likely to have been arrested for nontraffic offenses and violent crimes than nonvictimized controls.28 Astoundingly, nearly half of the victims of physical abuse and neglect in this sample had been arrested by the age of 32.

Conceptual models

Numerous cognitive and behavioral models have been proposed for understanding the cycle of violent and aggressive behavior. Social learning theory provides an explanation for the high violence potential observed in patients who have witnessed violence.29 For example, numerous studies confirm a link between observed violence and aggressive behavior in children and adolescents. These studies find that the link is an enduring one, in part because of the strength of vicarious social learning. Repeated exposure to community, domestic, or media violence is thought to promote the development of beliefs that violence and aggression are normal, acceptable responses, thereby increasing the potential to act aggressively. Furthermore, exposure to violence contributes to the development of a negativity bias, in that affected youth may exhibit more negative emotions, attribute negative intent to others, and be hypervigilant to negative stimuli.

Cicchetti and Lynch30 have described an ecological-transactional model to understand the process by which maltreatment occurs and development is shaped as a result of potentiating and compensatory risk factors at each level of social ecology-culture, community, and family. On the other hand, Nofziger and Kurtz31 have proposed a lifestyle model that focuses on the interaction between the person and his or her environment, noting that some adolescents are exposed to violence because they are involved in high-risk activities that put them at greater risk for violence exposure and subsequent victimization or perpetration. Along these lines, Stewart and colleagues32 found that adolescents who adopt a "code of the street" mentality actually have higher rates of victimization beyond what would be expected from living in a dangerous and disorganized neighborhood.

Impact of violence exposure

Studies related to the cycle of youth violence are important given the serious impact on affected individuals, communities, and society as a whole. Childhood abuse and repeated exposure to violence has a pervasive effect on a child's psychological and biological regulatory processes that can cause a complex set of reactions and lead to multiple psychiatric and functional impairments. In clinical settings, the link between violence exposure and depression,33 anxiety, posttraumatic stress disorder (PTSD),34 drug and alcohol abuse,35 and aggression and delinquency36 are frequently observed. Numerous other problems are associated with violence exposure, including a higher suicide risk,37,38 poor academic performance,39 and high-risk sexual behavior.40 Economically, direct and indirect costs of youth violence exceed $158 billion annually.41

Another important issue in understanding the impact of children's exposure to violence relates to neurological maturation and neurobiological processes in response to traumatic stress. The neurobiological sequelae of violence exposure and childhood abuse are well documented.42 Much of the work in this area has focused on altered catecholamine activity within the hypothalamic-pituitary-adrenal axis following exposure to traumatic events. Central catecholamine neurons play a critical role in the level of alertness, vigilance, attention, memory, fear conditioning, and cardiovascular response to life-threatening situations.43 Recurrent exposure to violence can lead to frequent flooding or dysregulation of noradrenergic and corticosteroid systems and contribute to heightened responsiveness and increased levels of aggression in persons with PTSD.44,45

It is believed that these chronically dysregulated systems have an eventual impact on structural and functional brain development. Research using functional MRI and positron emission tomography points toward dysfunction of the hippocampus in patients with PTSD.46 The hippocampus is believed to mediate emotional processing of complex visual stimuli and the integration of different aspects of memory, as well as the ability to locate a memory in time, place, and context. Prolonged periods of stress have been shown to correlate with elevated cortisol levels in the brain, which can damage the hippocampus in humans,47 thus potentially affecting a person's ability to accurately process and respond to incoming information.

Accordingly, brain development, stress regulation, and exposure to early traumatic experience are seen as interactive and cumulative in their influence on the development of impulsive violence and aggression.48

Psychopathology of trauma and impulsive violence

Aggressive behaviors can be classified into 2 general categories: premeditated aggression and impulsive aggression. While traumatized youth who perpetuate the cycle of violence may do so for a multitude of reasons-such as a means to express anger and resentment, revenge, distrust, as a self-protective need to attack before being attacked, to escape stressful circumstances, or to reenact previously abusive relationships-youth referred for psychiatric care typically exhibit reactive, impulsive forms of aggressive behavior. Increasingly, impulsivity, affective dysregulation, hyperarousal, and cognitive disorganization are seen as key concepts in understanding the determinants of violence and aggression among traumatized youth; consideration of these elements holds promise for the implementation of effective psychiatric interventions for those referred for outpatient or inpatient psychiatric treatment.

CASE VIGNETTE

Jackie is a 13-year-old African American girl referred to the emergency department with suicidal ideation after assaulting a peer at school. She has a long history of oppositional behavior, impulsivity, aggression, family dysfunction, school difficulties, and le- gal involvement, including 2 charges for assault.

Her mother reports that Jackie is surrounded by violence. As a child, Jackie witnessed domestic violence between her parents and engaged in frequent physical fighting with her siblings. She lives in a violent neighborhood, where she witnessed 2 neighborhood shootings and the death of a friend. In school, she frequently fights with peers and has developed a defiant, belligerent attitude toward school personnel.

A family assessment revealed a history of physical abuse, emotional abuse, and emotional neglect. Parental support and modeling have been problematic-her father has been in and out of jail for involvement with drugs, and her mother, also the victim of childhood abuse, is hostile and rigidly opinionated. Several immediate and extended family members have histories of aggressive behavior, including one who is in jail for murder.

Previous in-home and outpatient treatment efforts have been unsuccessful because Jackie often misses appointments, inconsistently takes prescribed medications, and refuses to follow rules at home. On admission to the hospital, she presents as loud, hostile, hypersensitive, intolerant, and threatening. She makes frequent verbal threats to explode, run away, or to commit suicide. She complains that people get on her nerves.

Cases such as Jackie's are all too common and illustrate the challenges faced by mental health professionals. For many adolescents treated within community-based clinics or hospital-based programs, violent and aggressive behavior is a frequent reason for referral and is often a central component of treatment planning. However, the psychopathological processes that underlie impulsive and aggressive behavior are complex. Diagnostically, patients with a history of trauma who exhibit high levels of affective instability, anger, and impulsivity may exhibit signs of an unstable mood disorder, eg, bipolar disorder or a mood disorder not otherwise specified, disruptive behavior disorder (attention-deficit hyperactivity disorder [ADHD], oppositional-defiant disorder, or conduct disorder), or PTSD. Often a core constellation of psychological deficits is present for traumatized and impulsively aggressive adolescents. Namely, impulsively aggressive adolescents typically have difficulty in recognizing, identifying, and verbalizing underlying emotions so that emotional flooding easily occurs and leads to rapid shifts in affect and behavior.

Deficient problem-solving skills are a common cognitive feature in that impulsive adolescents often have difficulty in drawing on intellectual resources to generate alterative options to resolve conflicts, resulting in rigid or negative thought processes. Traumatized adolescents are also likely to view their world as hostile and unsafe and see others as untrustworthy. Children who have been maltreated are hypervigilant to aggressive stimuli and prone to misinterpret verbal and nonverbal cues, making them more likely to perceive threats even when threats do not exist.

Perhaps as a consequence of neurodevelopment and neurocognitive function, impulsive adolescents who have been traumatized are also prone to have an exaggerated fight-flight response, whereby aggression can serve both as a means to protect the self as well as a means to destroy the other. Deep-seated feelings of shame and poor or disrupted interpersonal attachments make impulsive, traumatized adolescents hard to reach, guarded, prone to externalize and project blame, and resistant to sharing feelings openly with adults.

The Figure illustrates the cycle of violent behavior in adolescents.

Approaches to decrease risk of violence

Despite the strong association between violence victimization and later violence perpetration, not all children exposed to violence become aggressive and perpetuate the cycle of violence. Some withstand the negative effects of violence and show a pattern of resilient development. Many of the protective factors associated with decreased impact of violence exposure make intuitive sense.

Youths exposed to high levels of community violence but who live within families with high cohesion, high structure, effective parenting practices, and strong beliefs about the family are less likely to engage in violent behaviors than are youth in less well-functioning families.49,50 Supportive parent-child relationships characterized by communication, concern, and parent-connectedness have been linked to reductions in internalizing and externalizing behavior, including PTSD and aggression.51,52 Programs that build school safety also enhance adaptive functioning at school under conditions of high violence exposure.52 Thus, while supportive families, peers, and schools may not prevent an individual from being exposed to violence, they can indeed protect against the risk of subsequent emotional maladjustment, including the risk of violence.

Along these lines, community-based intervention programs in which mental health clinicians work side-by-side with police departments to rapidly respond to incidents of community violence have been shown to be especially helpful in addressing the emotional impact of traumatic violence.53 Therefore, interventions that involve an integrated approach that includes available family, school, and community supports would seem to be most likely to reduce the risk of violence among traumatized/violence-exposed youth.54,55

Once an adolescent is referred for mental health treatment because of impulsive aggressive behavior, a range of therapeutic options are available. Individual cognitive-behavioral therapy can be an effective method of improving problem-solving skills and social skill deficits.56 Dialectical behavior therapy may decrease internalizing and externalizing symptoms such as anger and depression in adolescents.57 Group therapy offers peer support and validation for one's reaction to traumatic events. Family therapy offers an emotionally neutral forum to discuss the antecedents and consequences of aggressive behavior in the home, and it is a link to the intergenerational transmission of violence.

Psychopharmacological therapies may also reduce symptoms of hyperarousal and impulsivity associated with PTSD, yet knowledge of medication treatments targeting aggression for children and adolescents is limited by a lack of reliable, well-controlled clinical trials. The FDA has yet to approve medication for pediatric use targeting PTSD or aggression. However, in 2 separate reviews of pharmacological treatment approaches for adults with PTSD,58,59 a number of options were recommended. Namely, SSRI antidepressants were suggested for targeting anxiety, mood, or re-experiencing symptoms. Sertraline60 and paroxetine61 are FDA-approved for adults with PTSD. Adrenergic agents, such as clonidine (an FDA-approved agent for the treatment of ADHD in pediatric patients) used either alone or in combination with an SSRI were viewed as useful for treating symptoms of hyperarousal and impulsivity.62 Supplementing with a mood stabilizer may be indicated for cases with severe affective dyscontrol, impulsivity, and anger.

Open label trials of carbamazepine,63 valproic acid,64 and topiramate65 have shown positive results for adults with PTSD comorbid with bipolar disorder. Atypical antipsychotic agents (risperidone and quetiapine) have the potential to reduce dissociation, self-injurious behavior, and aggression in adults.66,67

Conclusion

Given the rate at which America's youth are exposed to violence, mental health providers are encouraged to develop effective treatments that decrease the victim-to-perpetrator cycle of violence. Adolescents who exhibit symptoms of impulsive aggression are likely to lack prerequisite affect regulation skills to modulate aggressive impulses and will require integrated psychopharmacological and behavioral strategies to improve affect regulation and behavioral control. Approaches that integrate individual, family, community-based, and psychopharmacological interventions are required to address the pervasive and deleterious effects of violence exposure and childhood abuse.

References:

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