Are brain flaws the key to paedophilia?

They found distinct differences in brain activity among adults who had committed sexual offences involving young children.

The discovery raises the possibility that drug treatments might be used to control their urges.

Researchers found activity in parts of their brains was lower than in other volunteers when they were shown adult, erotic material.

It is the first 'real-time' evidence of different reactions in the thought patterns of paedophiles, said scientists at Magdeburg University, Germany, who recorded brain activity as subjects were thinking.

The study adds to mounting evidence that problems in certain areas of the brain may be to blame for sexual attraction to children.

The latest study used functioning magnetic resonance imaging on 13 male paedophiles as they looked at adult pornography.

Scans showed the reaction of the hypothalamus, which is involved in arousal and hormone release, and compared it with feedback from 14 normal volunteers.

Researchers found brain activity was less among the paedophiles, according to the study published in the journal Biological Psychiatry.

Scanning also showed a link with the frontal cortex, as more extreme paedophilic behaviour resulted in less activity here.

Dr John Krystal, editor of the journal, said: "The findings provide clues to the complexity of this disorder."

Lead researcher Dr Georg Northoff said: "Our results may be seen as the first step to establishing a neurobiology of paedophilia."