Antisocial behaviour in young men linked to low levels of stress hormone

A British research team have discovered a link between antisocial behaviour in male adolescents and reduced levels of the 'stress hormone' cortisol.

As a rule levels of cortisol in the body increase when people undergo a stressful experience, such as public speaking, sitting an exam, or having surgery.

Cortisol enhances memory formation and is thought to make people behave more cautiously and to help them regulate their emotions, particularly their temper and violent impulses.

The new research by scientists at Cambridge University which was funded by the Wellcome Trust, shows that adolescents with severe antisocial behaviour do not exhibit the same increase in cortisol levels when under stress as those without antisocial behaviour.

This suggests that antisocial behaviour, at least in some cases, may be seen as a form of mental illness that is linked to physiological symptoms involving a chemical imbalance of cortisol in the brain and body.

The research team led by Dr. Graeme Fairchild and Professor Ian Goodyer, recruited participants for the study from schools, pupil referral units, and the Youth Offending Service.

Over a period of several days samples of saliva were collected from the subjects in a non-stressful environment in order to measure levels of the hormone under resting conditions.

The young men then took part in a stressful experiment that was designed to induce frustration and samples of saliva were taken immediately before, during and after the experiment to track how cortisol changed during stress.

The differences between participants with severe antisocial behaviour and those without were most marked under stressful conditions - while the average adolescents showed large increases in the amount of cortisol during the frustrating situation - cortisol levels actually went down in those with severe antisocial behaviour.

The researchers say this suggests that antisocial behaviour may be more biologically-based than previously considered and some individuals are more vulnerable as with depression or anxiety, due to their biological make-up.

Dr. Fairchild says if it is understood precisely what underlies the inability to show a normal stress response, it may be possible to design new treatments for severe behaviour problems and also create targeted interventions for those at higher risk.

Dr. Fairchild says a treatment for this disorder would offer the chance to improve the lives of both the adolescents who are afflicted and the communities in which they live.

Government research shows that almost three-quarters of antisocial behaviour orders are given to offenders under the age of 21 and responding to incidents of antisocial behaviour costs the government approximately £3.4 billion per year.