A new Canadian study that found pedophiles have a strong tendency to be left-handed could help change decades of thinking about such sexual deviants -- and lead to new ways of combating the problem, says one of the researchers behind it. Most experts have theorized that pedophiles are motivated by psycho-social factors such as their early upbringing or sexual history, and treatment has responded accordingly. But the study published this month in Archives of Sexual Behaviour indicates there is a strong neurological factor, perhaps triggered by birth defects, that one day might be prevented. The researchers at Toronto's Centre for Addiction and Mental Health now plan to peruse MRI images of pedophiles for signs of brain abnormalities. "For more than a century, we've been putting a great deal of energy and effort into one class of theories about pedophilia and essentially ignoring biological components," said Dr. James Cantor, the study's lead author. "This is the first evidence that those theories can't be the whole story." Pedophiles present a formidable challenge to therapists, scientists and correctional authorities, with no evidence to date that their penchant for sex with children can ever be cured. Treatment often focuses on drugs that lower their libido and teaching strategies to avoid situations in which they victimize young people. There has not been much of a nature-versus-nurture debate in the field, either, said Dr. Cantor, and little research to explore the possible role of the brain. After previous work suggested a link between left-handedness and pedophilia, he and other scientists at the Toronto centre set out to examine the question more closely. They surveyed more than 400 sex offenders, using phallometric testing -- measuring blood flow in their penises when shown different images of potentially erotic stimuli -- and questions about their handedness. Among those whose primary sexual interest was children under 12, more than 30% were left-handed -- three times the rate in the general population or among sex offenders who favour adult victims. Similar associations have been found between left-handedness and major neurological disorders such as Down's syndrome and autism, the paper said. Although left-handedness has been linked to mathematical geniuses and musicians, it is more often associated with negative outcomes. The latest findings suggest there is a neurological component in pedophiles that may interact with psycho-social factors to distort their sexual behaviour, the study says. The brain problem may have occurred while their mothers were pregnant, Dr. Cantor said. "This is going to give us a clue as to what, in utero, went wrong. And this might be very helpful in preventing it in the first place," he said. "That would be of greater use to society [than a cure] because treatment only happens when the person has a victim, is apprehended and is more or less forced into treatment. If we can prevent it ahead of time, we not only prevent the repeat crimes, we prevent it in the first place." More research could eventually reveal factors -- such as drinking during pregnancy -- that cause such harm, said Dr. Martin Lalumiere, a forensic psychologist at the University of Lethbridge in Alberta. The new study is "very convincing," he said. "It makes a lot of sense that something like pedophilia would have a neurological basis," Dr. Lalumiere said. Pedophilia is almost exclusively a problem of men, he noted, and the male brain tends to be more fragile during development than that of the female. Dr. Cantor said he hopes other researchers will take the notion of a neurological cause of pedophilia more seriously and conduct further research to explore the connection. He and his colleagues plan to study brain scans of people who commit sexual offences against children and compare them to the brains of non-sexual offenders for signs of differences. The scientists hope to be able to identify parts of the brain that are different in pedophiles. The study also found a link, though less strong, between left-handedness and hebephiles -- men whose primary sexual interest is in pubescent children. © National Post 2005 http://www.canada.com/national/nationalpost/news/bodyandhe

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