Can brain scans predict criminal behavior?
Impulsivity could be a strong predictor of future criminal activity in convicts released from prison. A study in the Proceedings of the National Academy of Sciences found that inmates who showed high levels of impulsivity in brain scans were more likely to be re-arrested within four years of their release.
The researchers analyzed the brains of nearly 100 male inmates at the time of their release. They asked each inmate to quickly press a button when the letter X appeared on a computer screen, and to do nothing when the letter K appeared on the screen. The letter K appeared on the screen only 16 percent of the time so the men would not expect it. During the test, researchers also scanned the anterior cingulate cortex (ACC) of the men’s brains using a functional MRI scanner. The ACC is located at the front of the brain and is responsible for decision-making processes.
According to the results, the men who made more errors on the task had lower levels of activity in the ACC, indicating that they had a tendency to act on impulse rather than thinking through a decision. In a four-year followup, the men who had lower levels of ACC activity during the task were 4.3 times more likely to be re-arrested for nonviolent crimes and 2.6 times more likely to be re-arrested for all crimes.
The test is not accurate enough to be used for evaluations of criminals in real-world circumstances, but the research authors said that the results, ‘suggest a potential neurocognitive biomarker for persistent anti-social behavior.