A new study has revealed that paedophiles' brains are "abnormally tuned" to find the face of a child more attractive than that of an adult.

According to the results, images of children's faces prompted the regions of the brain associated with facial processing and sexual desire lit up in paedophiles.

The study conducted by researchers at the University of Kiel in Germany said their findings confirmed previous studies showing that human beings process faces according to the sexual orientation of the observer.

The researchers said that they found no evidence to suggest that paedophiles recruit a different brain network when exposed to faces of the preferred sex and age than individuals showing a normal preference for adults do and the same network is activated by the sexually preferred face, but the main difference is that in paedophiles that network is abnormally tuned to sexual immaturity.

The study was published in the journal Biology Letters.