The British study, which was conducted by researchers at Cambridge University, found a connection between the hormone cortisol and anti-social behaviors among boys ages 14 to 18 years old. This study appeared in the journal Biological Psychiatry.
The human body produces cortisol when undergoing stress. Cortisol is believed to make people become cautious and control their tempers and violent impulses when they find themselves in difficult circumstances.
The Cambridge researchers recruited 165 boys, some of whom were youthful offenders. The boys underwent cortisol level tests before and after they played a computer game rigged to make them angry. In most boys, cortisol levels rose. However, in boys with a history of difficult behaviors, cortisol levels tended to fall.
The Florida State research team analyzed data about family, friends, and genetics that had been collected from 1,816 middle school and high school students. The researchers found that boys who possess a certain gene variant were more likely to associate with delinquent friends. This did not hold true for girls with the variant.
"This research is groundbreaking because it shows that the propensity in some adolescents to affiliate with delinquent peers is tied up in the genome," said Dr. Kevin Beaver, an assistant professor of Criminology and Criminal Justice.
However, the team also found that environment plays a role in whether boys associate with delinquent peers. The boys with the gene variant who came from "low-risk" (nurturing) families did not tend to associate with delinquents.
The Florida State study appeared in the Journal of Genetic Psychology.
Posted By: Aspen Education Group