- Stimulation of prefrontal cortex has the potential to reduce a person’s intent to commit physical and sexual assault.
- Researchers conducted an experiment, in which they discovered people’s intentions to carry out violent acts were decreased by 54%.
- They also found a 31% jump in the perception that these violent acts were morally wrong.
Stimulation of prefrontal cortex — front brain region responsible for planning complex cognitive behavior, decision making, moderating social behavior and personality expression — can reduce intent to commit physical and sexual assault. It’s a new promising approach to prevent future violence.
Evidence from previous neurological researches and lesion studies show that patients with damaged prefrontal cortex exhibit more aggressive behavior. This usually modulates their aggression, violence and sometimes it extends to sexual offending.
In a randomized, double-blind, placebo-controlled study, performed at the University of Pennsylvania, researchers showed that people’s intentions to carry out violent acts can be reduced by up to 70 percent, by stimulating their prefrontal cortex. In fact, such methods could increase their perception that violent acts are morally wrong.
Researchers conducted an experiment to see what people think about certain violent acts. They selected 81 volunteers and randomly assigned them to one of two groups.
All participants were adults, evenly split between female and male, and ethnically diverse. To measure their personality and social adversity, they were all given a series of tests before participating in the experiment.
The first group received direct current stimulation to their prefrontal cortex for 20 minutes, while the members of the second group were given a low current for 30 seconds. Participants were completely unaware of their group assignment.
What first group received is known as transcranial direct current stimulation, which sends targeted impulses to the brain via electrodes attached to the scalp.
The next day, members of both groups read two stories: one portraying a picture of sexual assault and the other an act of physical aggression. Then, they were asked to rate their likelihood of doing similar acts on a scale of 0 to 10 (with 0 being absolutely no chance and 10 being 100% yes).
Roy Hamilton performing minimally invasive brain stimulation | University of Pennsylvania
To measure their aggression level (second task), they were given a picture of a doll and told that it represented their close friend or partner. Then, they were asked to release all negative energy towards that person by stabbing the doll with 0 to 51 small pins. The number of pins shows the level of aggression.
The intention to carry out physical and sexual assault was decreased by 54% in the group receiving prefrontal cortex stimulation. Researchers also found a 31% jump in their sense of moral wrongfulness about violent acts.
However, researchers didn’t notice any major difference between these two groups in the second test (doll-test) measuring aggression level.
These outcomes show that biological interventions — cognitive behavioral therapy — are capable of reducing violent behavior. Despite these exciting results, researchers make it clear that the study needs to be replicated, in order to make sure this kind of treatment really works.
The authors haven’t concluded anything yet. They want to test what happens when brain stimulation is applied for more than 20 minutes. What if they did it four times a week for a month?
At present, all these results are based on off-label medications and talk therapy. So anything researchers could add to the armamentarium to reduce future violent acts, the better.