Bullying and aggression, evasiveness and avoidance of responsibilities, and impulsivity and stealing-if these behaviors persist, the brain may hold the key in future studies.
A large longitudinal study found individuals with antisocial behavior that began in childhood and persists into midlife had structural brain differences than individuals who grow out of such behavior in adulthood or those who never displayed antisocial behavior. Carlisi and colleagues1 looked at a total of 672 brain scans from middle-aged participants, who, since birth, have been part of the Dunedin Study cohort in New Zealand.
Participants were classified by behavior, with 80 people (12%) with life-course persistent antisocial behavior; 151 (23%) with antisocial behavior in adolescence only; and 441 (66%) with no persistent antisocial behaviors. Participants (and parents and teachers while they were underage) were asked about key indicators of antisocial behavior, such as bullying, theft, lying, fighting, and vandalism, at age 7, 9, 11, 13, 15, 18, 21, and 26 years, with follow-up continuing through age 45 with 94% of living members of the group.
By looking at MRI scans at age 45, both cortical thickness and surface area were measured and analyzed and those with life-course persistent antisocial behavior had lower mean cortical thickness and reduced mean surface than people who did not have antisocial behaviors that persisted into adulthood. There was smaller surface area in a total of 282 out of 360 brain regions in participants with life-course persistent antisocial behaviors and 11 of 360 brain regions had a thinner cortex.
Lead author Dr Christina Carlisi from the University College London told Psychiatric Times, “Our findings support and build on earlier theories regarding the development and persistence of antisocial behaviour." She also says, "We are not able to make causal claims about whether the brain differences we observed were inherited and precede antisocial behaviour, or whether they were a result of a persistently antisocial lifestyle, but we are adding another piece of evidence at the biological level to the idea that there may be differences in the small group of individuals who persist with antisocial behaviour throughout their lives.”
In a news release, Dr Carlisi said, “There may be differences in . . brain structure that make it difficult for them to develop social skills that prevent them from engaging in antisocial behaviour. These people could benefit from more support throughout their lives.”2
1. Carlisi CO, Moffitt TE, Knodt AR, et al. Associations between life-course-persistent antisocial behaviour and brain structure in a population-representative longitudinal birth cohort. Lancet Psychiatry. February 17, 2020. https://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(20)30002-X/fulltext. Accessed February 20, 2020.
2. The Lancet Psychiatry: Life-course-persistent antisocial behaviour may be associated with differences in brain structure [news release]. Eureka Alert. February 17, 2020. https://www.eurekalert.org/pub_releases/2020-02/tl-pss021420.php. Accessed February 20, 2020.