Archives of Sexual Behavior, VoL 22, No. 6, 1993 Deficient Erotic Gender Differentiation in Pedophilia: A Follow-Up Kurt Freund, M.D.D.Sc. 1,2 and Michael Kuban, B.Sc. 1 Divided 262 phallometrically diagnosed pedophiles into heterosexual, homosexual, and bisexual groups, according to the sex of their victims. Each group was then divided into 3 subgroups according to degree of admitting to an erotic preference for children. They were compared among each other and with 47 self-professed heterosexual and 20 self-professed homosexual male volunteers phallometrically diagnosed as having an erotic preference for physically mature partners. The comparison was in regard to phallometrically assessed "erotic gender differentiation." Results demonstrate that gender differentiation of even the fully admitting heterosexual pedophiles was significantly weaker than that of the heterosexual controls, and the gender differentiation of the fully admitting homosexual pedophiles was significantly weaker than that of both groups of controls. Gender differentiation of the nonadmitting heterosexual pedophiles was significantly weaker than that of the heterosexual pedophiles who fully admitted to their paraphilia. This was demonstrated to be caused by the nonadmitters suppression of responses. KEY WORDS: pedophilia; phallometry;erotic gender differentiation;etiologicalmodel of pe- dophilia, INTRODUCTION Since the first indications that paraphilias may be more frequent in persons who have suffered very early brain damage, (Epstein, 1960, 1961; Kolarsky et al., 1967), the senior author has been searching for a deficiency in pedophiles that could have interfered with the usual development of an 1Department of Behavioral Sexology, Clarke Institute of Psychiatry, 250 College Street, Toronto, Canada, M5T 1R8. ~1"owhom correspondence should be addressed. 619 (D04-0002/93/1200-0619507.00/0 © 1993 Plenum Publishing Corporal.ion