Pedophilia Linked to Brain Development

By Mark Brennae
November 29, 2007

OTTAWA — Pedophilia may be the result of a person's brain not properly functioning due to faulty connections, according to a report released Wednesday by the Centre for Addiction and Mental Health.

"It's the most succinct proof that pedophilia is in the brain," said Dr. James Cantor, a CAMH psychologist and the study's lead scientist. "For a very long time, people have thought that being a pedophile was the result of being the victim of one's environment," - abused and sexually abused children, for example.

The study, published in the Journal of Psychiatry Research, challenges the commonly held belief that pedophilia is brought on by childhood trauma or abuse.

Its finding is the strongest evidence yet that pedophilia is instead the result of a problem in brain development, the CAMHsaid.

However, the study's conclusions suggest much more research needs to be performed to learn how the brain governs sexual interests.

Such information could potentially yield strategies for preventing the development of pedophilia, the CAMH said.

Currently, phallometric testing is performed to determine whether a person may be a pedophile.

"It's the most obvious test in the world," Cantor said.

A blood-pressure cup is placed on the patient's penis as he is shown pictures of adults and children and response of the penis is measure.

The CAMH study used MRIs and a sophisticated computer analysis technique to compare a group of pedophiles with a group of non-sexual criminals. The pedophiles had significantly less of a substance called "white matter" which is responsible for wiring different parts of the brain together.

Cantor said results of the study indicated that when something goes wrong in the development of a brain before birth or soon after - by contracting a virus, having poor nutrition, exposure to radiation, etc. - one side of the brain attempts to compensate resulting in the non-dominant side becoming dominant.

It is the dominant hemisphere of the brain, for instance, which determines which hand a person favours using.

Left-dominance usually means right-handedness while right-dominance generally results in a person preferring to use their left-hand.

James said his study found that while 10 per cent of the world's population is non-left-handed - either right-handed or ambidextrous - 30 per cent of pedophiles were non-right-handed.

"The fact that there is any association at all between pedophilia and handedness is a clue that something went wrong during development," Cantor said.

The study also concluded the IQs of pedophiles on average, to be 10 per cent lower than those of non-pedophiles and pedophiles even tend to be shorter than non-pedophiles.

"All of these (findings) suggest the brains are not organized the same way,"Cantor said.

However, because a person is wired in such a way doesn't mean they cannot control their behaviour, the study's lead scientist said.

"There is nothing in this research that says pedophiles shouldn't be held criminally responsible for their actions," said Cantor. "Not being able to choose your sexual interests doesn't mean you can't choose what you do."

A total of 127 men participated in the study; approximately equal numbers of pedophiles and non-sexual offenders.

The CAMH is one of North America's leading addiction and mental-health organizations and Canada's largest mental health and addiction teaching hospital.


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