A team of researchers from Spain was curious to know if people with high psychopathic traits have anomalies in the brain’s physical structures, which make them incapable of feeling regret or capable of manipulation and other antisocial behavior. They conducted an experiment in which they interviewed men convicted of intimate partner violence (IPV) and a control group with no history of violence to measure their psychopathic traits, followed by brain scans.
The results showed that men with thinner cortex in certain brain regions—particularly fronto-temporo-parietal areas—tended to display higher antisocial tendencies, regardless of their history of violence.
Fronto-temporo-parietal cortex regions refer to parts of the brain’s outer layer, which houses gray matter and supports functions such as sensory processing, motor control, and higher cognitive activities. The findings further reinforce a broader idea in neuroscience that regions in these brain regions play a major role in shaping behaviors such as callousness, a lack of empathy, and manipulative tendencies.
The findings are published in Aggression and Violent Behavior.
Markers of psychopathy
Psychopathy is a neuropsychiatric disorder that affects how people feel, think, and control their behavior. Individuals with strong psychopathic traits often show little empathy for others, have shallow emotional responses, and struggle with impulse control. Even though they make up only a small portion of the population, people with psychopathic traits are linked to a surprisingly large share of serious crime.
In recent years, researchers have increasingly tried to understand psychopathy by looking at the brain itself as advances in neuroimaging have made it possible to examine the brain’s structure in detail, including the thickness and volume of the cortex.
After sifting through over two dozen previous studies, the researchers found that the frontal, temporal, and parietal areas of the brain were linked to psychopathy. However, while earlier research had connected brain differences to psychopathic traits across various groups, there was not enough evidence to determine whether the same patterns held true for men convicted of domestic violence.
The team recruited 125 men to take part in the experiment— 67 intimate partner violence perpetrators and 58 controls with no such history.
To measure psychopathic traits, the researchers interviewed each man for 45 minutes, guided by a gold-standard tool called the PCL-R (Psychopathy Checklist-Revised). Each person was scored on behaviors such as lack of regret, manipulation, and impulsivity.
They also collected information on age, education, and substance use to make sure these factors did not influence the results. Each participant then underwent an MRI scan, the data from which were fed into a specialized software that measured the thickness of the cortex in specific regions.
They found that higher psychopathic traits were significantly and inversely correlated with reduced thickness in the left orbitofrontal cortex, the left insula, the bilateral superior frontal gyrus, the right dorsomedial prefrontal cortex, and the right anterior cingulate cortex.
Based on these findings and existing neuroscientific evidence, the researchers suggest that changes in gray matter on the left side of the brain may help explain traits such as poor decision-making and impulsivity. Differences on the right side may be linked to emotional and empathy difficulties, while reduced thickness in the insula may affect the ability to understand and interpret other people’s perspectives.
The researchers highlight that since brain scans cannot be faked the way answers during an interview or interrogation can, they can give forensic specialists and psychologists a clearer window into the mind. Combining neuroimaging with existing psychology tools can be used to build more accurate profiles of people with psychopathic traits and perpetrators of domestic violence.