This study investigated whether the previously observed association of pedophilia with lower IQs is an artifact of heterogeneity in referral source. The subjects were 832 adult male patients referred to a specialty clinic for evaluation of their sexual behavior. The patients' erotic preferences for prepubescent, pubescent, or adult partners were assessed with phallometric testing. Full scale IQ was estimated using six subtests from the WAIS-R. The results showed that the relations between pedophilia and lower IQ, lesser education, and increased rates of non-right-handedness were the same in homogeneous groups referred by lawyers or parole and probation officers as they were in a heterogeneous group referred by a miscellany of other sources. Those results, along with secondary analyses in the study, supported the conclusion that the relation between pedophilia and cognitive function is genuine and not artifactual. The findings were interpreted as evidence for the hypothesis that neurodevelopmental perturbations increase the risk of pedophilia in males.
Adams, H.E., Motsinger, P., McAnulty, R.D., & Moore, A.L. (1992). Voluntary control of penile tumescence among homosexual and heterosexual subjects. Archives of Sexual Behavior, 21, 17-31.
2.
American Psychiatric Association. (2000). Diagnostic and Statistical Manual of Mental Disorders (4th ed., text revision). Washington, DC: American Psychiatric Association.
3.
Batheja, M., & McManus, I.C. (1985). Handedness in the mentally handicapped. Developmental Medicine and Child Neurology, 27, 63-68.
4.
Blanchard, R., & Barbaree, H.E. (2005). The strength of sexual arousal as a function of the age of the sex offender: Comparisons among pedophiles, hebephiles, and teleiophiles. Sexual Abuse: A Journal of Research and Treatment, 17, 441-456.
5.
Blanchard, R., Barbaree, H.E., Bogaert, A.F., Dickey, R., Klassen, P., Kuban, M.E., et al. (2000). Fraternal birth order and sexual orientation in pedophiles. Archives of Sexual Behavior, 29, 463-478.
6.
Blanchard, R., Cantor, J.M., & Robichaud, L.K. (2006a). Biological factors in the development of sexual deviance and aggression in males. In H. E. Barbaree & W. L. Marshall (Eds.), The juvenile sex offender (2nd ed., pp. 77-104). New York: Guilford.
7.
Blanchard, R., Christensen, B.K., Strong, S.M., Cantor, J.M., Kuban, M.E., Klassen, P., et al. (2002). Retrospective self-reports of childhood accidents causing unconsciousness in phallometrically diagnosed pedophiles . Archives of Sexual Behavior, 31, 511-526.
8.
Blanchard, R., Klassen, P., Dickey, R., Kuban, M.E., & Blak, T. (2001). Sensitivity and specificity of the phallometric test for pedophilia in nonadmitting sex offenders. Psychological Assessment, 13, 118-126.
9.
Blanchard, R., Kuban, M.E., Blak, T., Cantor, J.M., Klassen, P., & Dickey, R. (2006b). Phallometric comparison of pedophilic interest in nonadmitting sexual offenders against stepdaughters, biological daughters, other biologically related girls, and unrelated girls. Sexual Abuse: A Journal of Research and Treatment, 18, 1-14.
10.
Bogaert, A.F. (2001). Handedness, criminality, and sexual offending . Neuropsychologia, 39, 465-69.
11.
Cantor, J.M., Blanchard, R., Christensen, B.K., Dickey, R., Klassen, P.E., Beckstead, A.L., et al. (2004). Intelligence, memory, and handedness in pedophilia. Neuropsychology, 18, 3-14.
12.
Cantor, J.M., Blanchard, R., Robichaud, L.K., & Christensen, B.K. (2005a). Quantitative reanalysis of aggregate data on IQ in sexual offenders. Psychological Bulletin, 131, 555-568.
13.
Cantor, J.M., Klassen, P.E., Dickey, R., Christensen, B.K., Kuban, M.E., Blak, T., et al. (2005b). Handedness in pedophilia and hebephilia . Archives of Sexual Behavior, 34, 447-459.
14.
Cantor, J.M., Kuban, M.E., Blak, T., Klassen, P.E., Dickey, R., & Blanchard, R. (2006). Grade failure and special education placement in sexual offenders' educational histories. Archives of Sexual Behavior, 35, 743-751.
15.
Coren, S. (1994). Twinning is associated with an increased risk of left-handedness and inverted writing hand posture. Early Human Development, 40, 23-27.
16.
Cornish, K.M., & McManus, I.C. (1996). Hand preference and hand skill in children with autism. Journal of Autism and Developmental Disorders, 26, 597-609.
17.
Davis, A., & Annett, M. (1994). Handedness as a function of twinning, age, and sex. Cortex, 30, 105-111.
18.
Dennis, M., & Barnes, M.A. (1994). Neuropsychologic function in same-sex twins discordant for perinatal brain damage. Journal of Developmental and Behavioral Pediatrics, 15, 124-130.
19.
Fisch, G.S., Simensen, R., Tarleton, J., Chalifoux, M., Holden, J.J., Carpenter, N., et al. (1996). Longitudinal study of cognitive abilities and adaptive behavior levels in fragile X males: A prospective multicenter analysis. American Journal of Medical Genetics, 64, 356-361.
20.
Freund, K. (1967). Diagnosing homo- or heterosexuality and erotic age-preference by means of a psychophysiological test. Behaviour Research and Therapy, 5, 209-228.
21.
Freund, K. (1981). Assessment of pedophilia. In M. Cook & K. Howells (Eds.), Adult sexual interest in children (pp. 139-179). London: Academic.
22.
Freund, K., Sedlacek, F., & Knob, K. (1965). A simple transducer for mechanical plethysmography of the male genital. Journal of the Experimental Analysis of Behavior8, 169-170.
23.
Freund, K., Seeley, H.R., Marshall, W.E., & Glinfort, E.K. (1972). Sexual offenders needing special assessment and/or therapy. Canadian Journal of Criminology and Corrections, 14, 3-23.
24.
Frith, C., & Dolan, R.J. (1998). Images of psychopathology. Current Opinion in Neurobiology, 8, 259-262.
25.
Frydman, M. (1996). The smoking addiction of pregnant women and the consequences on their offspring's intellectual development. Journal of Environmental Pathology Toxicology and Oncology15, 169-172.
26.
Glueck, B.C., Jr. (1955). Final report: Research project for the study and treatment of persons convicted of crimes involving sexual aberrations, June 1952 to June 1955. New York: New York State Department of Mental Hygiene.
Grouios, G., Sakadami, N., Poderi, A., & Alevriadou, A. (1999). Excess of non-right handedness among individuals with intellectual disability: Experimental evidence and possible explanations. Journal of Intellectual Disability Research, 43, 306-313.
29.
Hardyck, C., & Petrinovich, L.F. (1977). Left-handedness. Psychological Bulletin,84, 385-404.
30.
Hayes, A., & Batshaw, M.L. (1993). Down syndrome. Pediatric Clinics of NorthAmerica, 40, 523-535.
31.
Ishai, A. (2007). Sex, beauty and the orbitofrontal cortex. International Journal ofPsychophysiology, 63, 181-185.
32.
Kozma, C. (1998). On cognitive variability in velocardiofacial syndrome: Profound mental retardation and autism. American Journal of Medical Genetics, 81, 269-270.
33.
Kuban, M., Barbaree, H.E., & Blanchard, R. (1999). A comparison of volume and circumference phallometry: Response magnitude and method agreement. Archives of Sexual Behavior, 28, 345-359.
34.
Mahoney, J.M., & Strassberg, D.S. (1991). Voluntary control of male sexual arousal. Archives of Sexual Behavior, 20, 1-16.
35.
Marlow, N., Roberts, B.L., & Cooke, R.W.I. (1989). Laterality and premature birth. Archives ofDisease in Childhood, 64, 1713-1716.
36.
Needleman, H.L., Schell, A., Bellinger, D., Leviton, A., & Allred, E.N. (1990). The long-term effects of exposure to low doses of lead in childhood. An 11-year follow-up report. New England Journal of Medicine, 322, 83-88.
37.
Neyens, L.G., Aldenkamp, A.P., & Meinardi, H.M. (1999). Prospective follow-up of intellectual development in children with a recent onset of epilepsy. Epilepsy Research, 34, 85-90.
38.
O'Callaghan, M.J., Tudehope, D.I., Dugdale, A.E., Mohay, H., Bums, Y., & Cook, F. (1987). Handedness in children with birthweights below 1000 g. Lancet, 1(8542), 1155.
39.
Oldfield, R.C. (1971). The assessment and analysis of handedness: The Edinburgh Inventory. Neuropsychologia, 9, 97-113.
40.
Olson, H.C., Feldman, J.J., Streissguth, A.P., Sampson, P.D., & Bookstein, F.L. (1998). Neuropsychological deficits in adolescents with fetal alcohol syndrome: Clinical findings. Alcoholism, Clinical and Experimental Research, 22, 1998-2012.
41.
Ponseti, J., Bosinski, H.A., Wolff, S., Peller, M., Jansen, O., Mehdorn, H.M., et al. (2006). A functional endophenotype for sexual orientation in humans. Neurolmage, 33, 825-833.
42.
Powls, A., Botting, N., Cooke, R.W.I., & Marlow, N. (1996). Handedness in very-low-birthweight (VLBW) children at 12 years of age: Relation to perinatal and outcome variables. Developmental Medicine and Child Neurology, 38, 594-602.
43.
Radcliffe, J., Bunin, G.R., Sutton, L.N., Goldwein, J.W., & Phillips, P.C. (1994). Cognitive deficits in long-term survivors of childhood medulloblastoma and other noncortical tumors: Age-dependent effects of whole brain radiation. International Journal of Developmental Neuroscience, 12, 327-334.
44.
Ross, G., Lipper, E., & Auld, P.A.M. (1992). Hand preference, prematurity and developmental outcome at school age. Neuropsychologia, 30, 483-194.
45.
Safron, A., Barch, B., Bailey, J.M., Gitelman, D.R., Parrish, T.B., & Reber, P.J. (2007). Neural correlates of sexual arousal in homosexual and heterosexual men. Behavioral Neuroscience, 121, 237-248.
46.
Schachter, S.C., Boulton, A., Manoach, D., O'Connor, M., Weintraub, S., Blume, H., et al. (1995). Handedness in patients with intractable epilepsy: Correlations with side of temporal lobectomy and gender. Journal of Epilepsy, 8, 190-192.
47.
Searleman, A., Cunningham, T.F., & Goodwin, W. (1988). Association between familial sinistrality and pathological left-handedness: A comparison of mentally retarded and nonretarded subjects. Journal of Clinical and Experimental Neuropsychology , 10, 132-138.
48.
Seto, M.C. (2007). Pedophilia and sexual offending against children: Theory, assessment, and intervention. Washington, DC: American Psychological Association. (In press).
49.
Seto, M.C., Cantor, J.M., & Blanchard, R. (2006). Child pornography offenses are a valid diagnostic indicator of pedophilia. Journal of Abnormal Psychology, 115,610-615.
50.
Soper, H.V., Satz, P., Orsini, D.L., Henry, R.R., Zvi, J.C., & Schulman, M. (1986). Handedness patterns in autism suggest subtypes . Journal of Autism and Developmental Disorders, 16, 155-167.
51.
Taylor, H.G., Yeates, K.O., Wade, S.L., Drotar, D., Klein S.K., & Stancin, T. (1999). Influences of first-year recovery from traumatic brain injury in children. Neuropsychology, 13, 76-89.
52.
Tellegen, A., & Briggs, P.F. (1967). Old wine in new skins: Grouping Wechsler subtests into new scales. Journal of Consulting Psychology, 31, 499-506.
53.
von Krafft-Ebing, R. (1965). Psychopathia sexualis: A medico-forensic study (H. E. Wedeck, Trans.). New York: Putnam. (Original work published 1886).
54.
Wechsler, D. (1981). Wechsler Adult Intelligence Scale-Revised Manual . New York: Psychological Corporation .
55.
Wesseling, J., VanDriel, D., Heymans, H.S., Rosendaal, F.R., Geven-Boere, L.M., Smrkovsky, M., et al. (2001). Coumarins during pregnancy: Long-term effects on growth and development of school-age children. Thrombosis and Haemostasis, 85, 609-613.
56.
Williams, C.S., Buss, K.A., & Eskenazi, B. (1992). Infant resuscitation is associated with an increased risk of left-handedness. American Journal of Epidemiology , 136, 277-286.
57.
Williams, S.M. (1986). Factor analysis of the Edinburgh Handedness Inventory . Cortex, 22, 325-326.
