Drug use, crime, violence, and other anti-social behaviors are typically considered social problems. And, of course, they are — both in the sense that they have an impact on the larger community and because aspects of the social environment, such as socio-economic status and exposure to violence, influence risk for these behaviors. But recent findings from the field of neuroscience indicate that some anti-social behaviors are partly the result of brain involvement, including difficulties regulating emotions and stress, attention deficits, impulsivity, poor decision-making, and low verbal ability. There is evidence that these neurobehavioral problems are more likely to develop in community and home environments with poor resources and a higher concentration of risk factors that trigger them.
An emerging emphasis in neuroscience is on the potential to translate knowledge about the brain’s involvement in these problems to develop solutions — including behavioral interventions — to prevent drug abuse and violence. Targeted behavioral and social interventions can help rewire dysfunctional neural circuits to compensate in part for poor environmental conditions and promote more advantageous outcomes. Such new, neuroscience-informed strategies for preventive and treatment interventions may minimize risk-taking behaviors and improve healthy decision-making, thereby reducing drug use and violence.
Dr. Diana H. Fishbein, a senior fellow directing the Transdisciplinary Science and Translational Prevention Program for RTI International, and her colleague the neuroscientist Dr. Dana Eldreth argue that, to be more effective, programs to prevent substance use and violence should include a focus on the brain. Their research examines interventions that promote brain plasticity, and they use state-of-the-art brain-imaging techniques to measure it.
Brain World: Why do you think there is hesitation on the part of the lay public and people in the helping professions to accept that biology plays an important role (and that environmental factors have a biological impact) in drug abuse and violence?
Diana Fishbein: Anti-social behaviors harm others, so people need and want justice. Closure regarding harmful behaviors by the criminal justice system is comforting. Also, any information or viewpoint that potentially opposes free will is contrary to Western society’s beliefs and justice system, which tends to be based on blame and retribution.
But what neuroscience research tells us is that there are reasons why people engage in anti-social acts. Of course, biological underpinnings don’t excuse these behaviors. Knowing the mechanisms, however, can give us valuable information for preventing such behaviors. Risk factors or “triggers” for behavioral problems (for exaple, stress, experiencing, or witnessing violence) are concentrated in low-income areas, so there are more difficulties related to behavioral and physical health in these places.
Since the external triggers for these problems are less common in areas of higher income or socio-economic status, behavioral problems are more likely to remain dormant there, even in the presence of a genetic vulnerability. The environmental risk factors evident in low-income areas or in dysfunctional homes have an impact on physiology. There is a great deal of evidence, for example, indicating that such environments increase stress sensitivity and maladaptive reactions to stress, and in some cases can even delay development of the child’s brain.
This is why it is important to look at physiology when considering the pathway from low income and disadvantage to various behavioral and health problems. Researchers can use those physiological measures to gauge the impact of interventions because stress responses and other functions have potential to change.
That said, substance misuse and violence are complex phenomena without easy fixes. To address this complex issue, we need multiple perspectives and approaches, from genetic to neurobiological to psychological to social — as well as an understanding of how all these levels interact. Yet there is a tendency for research to be compartmentalized and, therefore, not integrated among disciplines. To me, the best prevention research is interactional.
For example, Dr. Gene Brody [at the University of Georgia] looks at how gene variants interact with the environment to influence behavior that puts youth at risk. He finds that a genetic vulnerability is less likely to be expressed if the environment is protective. This kind of work is helping us better understand something very important that we don’t know much about: the pathways and mechanisms whereby environment and biology interact to influence behavior. Particularly, how do poverty and enrichment interact with biology to influence risk for aggression, violence, and substance misuse?
BW: Where is the prevention field at the moment in terms of using biological measures in its research?
DF: Generally, it is very early, but use of biological measures depends on the specific area of interest. Prevention scientists — researchers who study the patterns of problems such as drug use, violence and delinquency, as well as the factors that lead to them and interventions to reduce them — are starting to get onboard. However, policymakers, practitioners, and the public have not really accepted this approach yet. Some prevention scientists are seeking collaborations with interested biological scientists.
Such collaborations would, for example, examine changes in brain-activity patterns and neurobehavioral characteristics (for example, reduced impulsivity, better emotional regulation) that correlate with participating in an intervention. Researchers who have developed and tested model prevention programs, ones found to be effective, think they may be able to improve these interventions by using neural and other physiological data to suggest what mechanisms are involved in program outcomes.
Examples of model prevention programs include Tools of the Mind, a preschool curriculum that strengthens children’s ability to pay attention and control their behavior; the Promoting
Alternative Thinking Strategies (PATHS) curriculum, a school-based program that helps children develop socio-emotional skills that help them to avoid using aggression and other negative responses; and the “Good Behavior Game”: a classroom-management program designed to promote self-control and socialize children for the role of student in elementary school.
There is a need for intervention improvement — even the most effective interventions have only a small to moderate effect. Many individuals who receive programs do not benefit. Why? Biological measures may give important clues to help us answer that question. That information can help determine what interventions work best for who, why, and under what circumstances.
Dana Eldreth: The translation of this sort of work is further along in areas of psychology and psychiatry. For example, researchers have used neuroimaging to examine the mechanisms of cognitive-behavior therapy (CBT) [a psychotherapy that is effective for a wide range or problems including depression, anxiety disorders, and substance abuse]. Pre- and post-intervention neuroimaging scans show that CBT changes the brain in individuals who show behavioral improvements.
So researchers use tasks that tap into neurocognition, for example, executive functions [a wide range of abilities including planning, attention, and working memory] and emotion regulation [the way you regulate your emotional reactions to experiences], which require skills targeted by CBT to find out what part of the treatment is responsible for the improvement. Neuroimaging can determine what neural changes accompany improvement in these functions.
This research approach has not really been applied in the study of high-risk behaviors and impulse-control disorders, and this is what we are trying to do in our research. We want to compare what has changed in the brain for those who do not respond to the PATHS curriculum and hope to conduct similar studies on the Good Behavior Game intervention. These are difficult studies to do. For example, the intervention may have been experienced in early grade school, so it is difficult to sort out the effects on behavior much later.