IS THE BRAIN TO BLAME? SEARCHING FOR THE ORIGINS OF VIOLENCE

Biology 202
2001 Third Web Report
On Serendip

IS THE BRAIN TO BLAME? SEARCHING FOR THE ORIGINS OF VIOLENCE

Janine R. Fuertes

Before we can begin to answer these questions, however, we must first recognize that not all acts of violence are the same. Certainly the child that throws his toys across the room in anger does not compare to the serial rapist who takes pleasure in attacking women. However since we are primarily interested in tracing the roots of violent behavior, it would be most helpful to look back to the time when our thoughts and actions were only beginning to be shaped, when our minds were impressionable and constantly curious - our childhood. And so we will examine the three main categories of violence observed in childhood - community and school violence, media-related violence, and violence in the home (1) - so that we may begin to paint a picture of the environment in which the violent individual is born.

It is no secret that violence in the schools and community has frighteningly been on the rise in America. In fact, from 1986 to 1996 there was a 60% increase in juvenile violence, which now accounts for 19% of all violent crime (1). From the amount of school shootings that have occurred in the past 5 years, as well as a plethora of unpublicized acts of intimidation, threat, and simple assault occurring in the classroom, it is reasonable to conclude that for many young children, school is not the safe haven that it was once believed to be. Instead, it is a place of constant fear, where the possibility of harm is an undeniable threat.

In places where violence in the community is not a threat, children are still bathed with violent images at every turn, simply at the click of a button. Now more than ever the media has been flooded with aggressive acts ranging from the punches and kicks of the newest videogame, to the gruesome murders of the last big-screen thriller. It has also been estimated that by the time a child turns 18, he or she will have viewed at least 200,000 acts of violence on television (1). Even if the child has grown up with a solid, emotional and social background, he is still vulnerable to these overwhelming displays of media violence and is often left with a greater tendency towards aggressive and antisocial behavior (1). For those who do experience violence in the household, watching these powerful acts on television serves to reinforce the cultural values they see modeled in their everyday lifestyles (1).

But for the majority of children, the greatest threat of exposure to violence comes from the home. In a 1995 FBI report, it was concluded that 27% of all violent crime involves family on family violence, a vast underestimation considering that many people are too afraid to report incidences against those closest to them (1). The child may be the direct receiver of the violent act, or a witness to the crime committed against his mother, father, or sibling. Often times the child becomes the victim when he attempts to intervene in order to protect another family member. Regardless of who receives the violence, all are affected emotionally through humiliation, degradation, and the threat of future assault (1).

What impact do these experiences with violence have on the developing child? And why is it that many children who have lived through violent circumstances grow up to be healthy, non-aggressive adults? As mentioned earlier, all forms of violent behavior affect a child's mind. However, the extent to which one is influenced can vary tremendously due to a number of factors. Some of these factors include the type of violence, the pattern of violence, the presence or absence of caring support-givers, and most importantly, the age of the child at the wake of violence (2). So while two children may be raised in a seemingly similar environment, one may grow up to be a convicted murderer while the other a well-functioning, healthy individual. Generally a child hit by a parent in a moment of weakness will not be as likely to develop violent tendencies as one who was repeatedly beaten as a means of punishment. Similarly, a 12-year-old may appear fine after having been neglected by his parents for a week, whereas an infant may literally die if given the same treatment.

For some children exposed to violence, a safe community may help to buffer the effects of a violent home (2). But for those children who witness and experience violence at every turn, in their families, schools, and communities, adapting to the atmosphere of fear becomes necessary. What occurs in this type of environment is much more than simply a "monkey see, monkey do" event. While it is true that many children grow to imitate the violent behaviors set as examples by those around them, others start to display aggressive behavior because their minds have literally become adjusted to doing so. This is because the adaptation to the persisting fear can go so far as to alter the development of the child's brain, which in turn may result in changes in his physiological, emotional, cognitive, behavioral, and social functioning (1). Hence, we begin to see a biological basis for the origin of violence.

The human brain is remarkable in its ability to work in a use-dependent fashion - that is to say that the more a neural system is activated, the more it will change (1). During a child's development, all of the patterned, sensory experiences result in the subsequent organization of neural systems and functioning. The brain displays functions that mirror the repetitive experiences of childhood (1). Different areas of the central nervous system are forming at different times, and so at some points, it is more sensitive to organizing experiences (2). Disruptions of the neurochemical signals during these periods may potentially lead to abnormalities in neurodevelopment - some of which are irreversible (2). Evidence shows that exposure to violence or trauma alters the developing brain by altering normal neurodevelopmental processes (2). Trauma influences the intensity and nature of the sensory and affective experience of events in childhood, while threat activates the brain's stress response, which can subsequently alter neurogenesis, synaptogenesis, and neurochemical differentiation (1). Thus, exposure to violence during childhood activates a number of threat responses, which can alter the developing brain and modify its functioning. These changes will depend on the type of violence experienced and how the child responds to the threat (1).

Other studies have been conducted in order to shed some light on the connection between the brain and a person's violent tendencies. One such study was performed at the University of Wisconsin-Madison, where psychologists observed brain imaging data from a large group of people with aggressive personality disorder, those with childhood brain injuries, and convicted murderers (3). The project focused on specific brain regions: the orbital front cortex, which plays an important role in controlling impulsive outbursts, the anterior cingulate cortex, which recruits other brain regions when conflicts arise, and the small amygdala, which is involved in producing a fear response and other negative emotions (3). The results showed that in many of the study groups, normal activity in the orbital and anterior regions was absent, while the amygdala showed normal and sometimes even heightened activity (3). The inability of the two cortical regions to successfully counteract the actions of the amygdala may explain why threatening situations can become intense in some individuals (4).

The same project also described subjects with a genetic deficit that causes an imbalance in serotonin levels (3). The serotonin system employs the brain regions discussed above, and disruptions to the serotonin levels has been linked to increased aggression (3). The analysis showed that these brain regions that control emotion showed less activity in the subjects who carried this genetic abnormality (3).

Of course, this study is only the first of a series that will need to be conducted before accurate conclusions can be made. However its findings are highly significant because it may help doctors find physical traits that could identify children at risk for violent behavior (4). Moreso than this, if future results display the same outcomes as Davidson's project, the implications for a genetic basis for the origin of violence and not just an adaptive, biological framework would become a reality. But then where would that leave our society and our methods of violence control? Knowing that a particular individual might have a predisposition towards aggressive behavior does not necessarily mean he will develop it someday, and perhaps the "knowing" would end up causing more harm than good. It is important to realize that though we may eventually be able to predict aggressive tendencies, we must use the skill with caution for it may lead to undeserved whispers and stares from the community. What we really must look at is the fact that this study points to two causes, genetics and poor environmental history, as contributors to impulsive violence (4). Separately these factors may be warning signs for future violent behavior, but together they pose a much greater threat in an individual. So while the future may hold and accurate presentation of the violent person's makeup and background, in our system, everyone is still innocent until proven guilty, and labels should not be placed where harm has not been done. Therefore rather than focusing on how to predict a person's predisposition for violence, attention should instead be concentrated on prevention and intervention to reduce violence.

In conclusion, the true key in understanding the origins of violence remains in understanding the broader picture - the type of environment that raised the individual, the effect it had on his developing brain, and the already existing, genetic predisposition the person has towards violence. I have learned that the debate over nature vs. nurture has resulted in a tie, with both working hand in hand to create the violent personality, and that one without the other often leads to no signs of violence at all. I have also learned that though we cannot as a just society judge people on the basis of what they may or may not do, we can use the various studies conducted to help in developing ways to control the violence that already exists. Perhaps in doing so, we can restructure our society to be one that is less violent, less threatening, and more fit for our future generations.

WWW Sources

2) Incubated in Terror: Neurodevelopmental Factors in the 'Cycle of Violence'

3)Brain Study Sheds Light on Impulsive Violence , on the Science Daily website

4)Caution Urged for Brain Research on Violence