4. Meeting conflict
The Biology of Violence
an interview with
Debra Niehoff
Q: In Biology of Violence, you examine 20 years of research on the brain and on violence. What are the major conclusions you’ve found?
A: The biggest lesson we have learned from brain research is that violence, like all complex human behaviors, is the result of a developmental process, a lifelong interaction between the brain and the environment.
The way the brain keeps track of our experiences is through the language of chemistry. It’s an organic historian. These experiences get recorded as changes in the chemistry and the hormones of the nervous system and particularly the circuitry for emotion and our responses to stress.
When we come to a new interaction with a new person, we bring to that a neuro-chemical profile that is based on answers to some very important questions we’ve answered over a period of years: Is the world safe? Are people generally trustworthy? What do I know about this person from looking at her/him? What might I know from other sources?
That sets off some emotional reactions within us and that emotion, the chemistry of those feelings, is translated into our responses. Then that person reacts to us, and our emotional response to their reaction also changes brain chemistry a little bit. So after every interaction, we update our neuro-chemical profile of the world and of that relationship.

Q: So how does the interaction between brain and environment begin?
A: The amazing thing about the human brain is that it is so flexible, and it is very adaptable. We are born with some things. We don’t come with a blank slate. We have a human brain architecture; we have the desire to be social; we have the ability to use tools like language; and we have a basic way of interacting with the world. Some babies are very excitable, some are very laid back. And those differences in activity level, reactivity, and sensitivity are the basics of temperament. It’s what we bring to the situation. Then the way those characteristics fit with our particular environment goes on to shape that temperament and our behavior.
The most important programming goes on in the circuitry that governs emotion and response to the challenges of life, the stress. Our ability to shape those neuro-systems to fit our own particular environment helps us to adapt to a particular situation. So, if we find ourselves in an unsafe environment, we can adapt our behavior to survive. In comfortable, accommodating circumstances, our behavior changes in a different way.

Q: And do we have conscious control over changing that template?
A: As adults, with some outside help, we can look at our patterns of behavior and we can use conscious means to change and control some of those emotional responses. Children less so, because those systems are among the slowest in the brain to develop.

Q: By what age do those systems tend to be fully developed?
A:The parts of the brain that we like to think of as being rational or reasoning – able to work with ideas rather than simply react to the environment –take a good 20 years to develop. The prefrontal cortex, which is one of the best developed areas in human beings, is really important to representational thinking or the ability to manipulate ideas and thoughts. Those functions of the brain aren’t completely mature until early adulthood.

Q:And how does that relate to violence?
A:Well, that circuitry is overlaid and connected to the circuitry of emotions. So the two work hand in hand. Aggression, the ability to use force, is a natural part of the behavior repertoire of living things. Aggression is important. If we couldn’t be aggressive, we couldn’t defend ourselves, or our children. We wouldn’t be able to compete for jobs or compete in sports. But when that normal behavior becomes inappropriate, when it is directed toward the wrong person, in the wrong place, at the wrong time, and with the wrong intensity, then it becomes violent and it becomes unacceptable.
When that happens, there is a change in the person’s ability to accurately determine whether something is a real threat. Either they are overreacting to benign stimuli, or they are not reacting to very real threats, like the threat of punishment. Something has gotten out of whack in their ability to understand and react correctly to their environment. The frontal cortex plays a big role in providing additional information to our emotional reactions, to clarifying those reactions by saying, “Wait a minute, that’s not really the way things are working. Step back and take a minute to think.”
If a person has come to believe that the world is against them, and they are overreacting to every little provocation, these violent reactions get beyond their ability to control because they are in survival mode.