"Long before it's in the papers"
January 28, 2015


A predisposition to pedophilia?

Oct. 23, 2007
Courtesy Centre for Addiction 
and Mental Health
and World Science staff
Updated Oct. 24

Male pe­do­philes are shorter than av­er­age, hint­ing at pos­si­ble bi­o­log­i­cal factors be­hind pe­do­phi­lia, a study has found.

Sex­u­al abuse in child­hood can lead to men­tal prob­lems in­clud­ing de­pres­sion, sub­stance ab­use and anx­i­e­ty dis­or­ders, ac­cord­ing to psy­chol­o­gists. (Photo cour­tesy morgue­File)

This does­n’t mean pe­dophiles aren’t “crim­i­nally re­spon­si­ble for their be­hav­ior,” said psy­chol­o­gist James Can­tor of Toron­to’s Cen­tre for Ad­dic­tion and Men­tal Health, the lead re­search­er. “But the dis­cov­ery of bi­o­log­i­cal mark­ers for pe­dophilia has im­por­tant im­plica­t­ions for fu­ture study and pos­sibly treat­ment.”

The re­sults sug­gest pe­dophiles ex­pe­ri­enced pre-birth con­di­tions that af­fect­ed their brain or oth­er phys­i­cal de­vel­op­ment, said the in­vest­i­ga­tors. The find­ings ap­peared in the Oct. 19 ad­vance on­line is­sue of the re­search jour­nal Sex­u­al Abuse

Dif­fer­ences in av­er­age height are al­so found in oth­er ill­nesses, the sci­ent­ists said. 

Can­tor and col­leagues re­viewed files of over 1,000 men as­sessed for pe­dophilia or oth­er sex­u­al dis­or­ders be­tween 1995 and 2006 at the Kurt Fre­und Lab­o­r­a­to­ry in To­ron­to. The av­er­age height dif­fer­ence was 2 cm (0.8 inch­es), they added, si­m­i­lar to shorter height as­so­ci­at­ed with schiz­o­phre­nia or Alzheimer’s dis­ease. 

Pre­vi­ous re­search by the group had al­so found pe­dophiles suf­fered more head in­ju­ries as chil­dren, have low­er IQs, are three times more likely to be left-hand­ed, and failed school cours­es sig­nif­i­cantly more of­ten than av­er­age.

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Pedophilic males are shorter than average, hinting at a possible biological basis for pedophilia, a study has found. This doesn’t mean pedophiles aren’t “criminally responsible for their behavior,” said psychologist James Cantor of Toronto’s Centre for Addiction and Mental Health, the lead researcher. “But the discovery of biological markers for pedophilia has important implications for future study and possibly treatment.” The results suggest pedophiles experienced pre-birth conditions that affected their brain or other physical development, said the researchers, whose findings are to appear in the research journal Sexual Abuse. They reviewed files of over 1,000 men who were assessed for pedophilia or other sexual disorders between 1995 and 2006 at the Kurt Freund Laboratory in Toronto. Difference in average height is also found in other illnesses with biological links, Cantor and colleagues said. The average difference was 2 cm (0.8 inches), they added, similar to shorter height associated with schizophrenia or Alzheimer’s disease. Previous research by the group had also found pedophiles suffered more head injuries as children, have lower IQs, are three times more likely to be left-handed, and failed school courses significantly more often than average.