You can pick out a criminal ‘while they’re still at nursery’
HARDENED criminals have an abnormal brain structure and display aggressive behaviour from early childhood, a major study suggests.
Researchers at University College London found that repeat adult offenders have a smaller brain surface area – which they said should be seen as a handicap.
Crime could be slashed, they said, if antisocial children were identified early and their parents offered specialist help before bad behaviour is ‘entrenched’.
Scientists conducted MRI brain scans of a representative sample of 672 adults who had been tracked by scientists for 45 years.
The scans revealed that adults with multiple convictions or a history of bad behaviour had smaller brains, with reduced surface area in key regions linked to motivation and emotions. The study, published in The Lancet Psychiatry,
revealed that these brain abnormalities are associated with a higher risk of reoffending.
The participants were asked about their history of antisocial behaviour including stealing, bullying, lying, aggression or violence.
Researchers also looked at their criminal records and questioned their teachers and nursery staff, identifying a group of 80 adults with a ‘ persistent’ history of antisocial behaviour and physical violence, ranging from biting other children in nursery to domestic violence as an adult.
This group, estimated to form around 5 to 10 per cent of western populations such as the UK, had a smaller average size in 282 of 360 brain regions.
Study author Professor Terrie Moffit said: ‘They are actually operating under some handicap at the level of the brain. This changes my conception... to thinking of someone who is living life with some level of disability, and coping with that as part of their lifestyle.
When they were very small children, they tended to bully other children at nursery school.
‘If they wanted a toy they took it and hit the other children get it. So they have always solved problems in that aggressive way.’
Youth offenders with one conviction but no lifelong history of antisocial behaviour did not have any structural abnormalities in their brain, the study found.
Experts said they hope this will prompt a rethink on youth offending and encourage more professional support to be given to naughty children to reduce crime in the long term.
Professor Moffit said: ‘ Those one-off offenders don’t appear to have poor brain health, and that suggests that they really are very good candidates to reform and rehabilitate. The peak age for crime is between 16 and 25. The vast majority of young offenders will have only a short-term brush with law and then they grow up to become law-abiding.
‘But there are just a few offenders who take a persistent path, starting as a young child with aggressive conduct problems and eventually sinking into a longterm lifestyle of repetitive serious crime that lasts into adulthood.’
Co-author Professor Essi Viding said it is important this group is not demonised but seen as individuals who need help, adding: ‘At the moment in the UK we don’t have a very good way of catching these people early on.’
The authors say the study provides the first robust evidence that underlying neuropsychological differences are linked to antisocial behaviour into and throughout adulthood. But more research is needed to see whether the smaller parts of the brain are the cause – or are a result of substance abuse, low IQ and mental health problems.
‘They tend to bully other children’