"A 2012 literature study by clinical psychologist James Cantor, when comparing homosexuality with paraphilias, found that both share "the features of onset and course (both homosexuality and paraphilia being life-long), but they appear to differ on sex ratio, fraternal birth order, handedness, IQ and cognitive profile, and neuroanatomy". The research then concluded that the data seemed to suggest paraphilias and homosexuality as two distinct categories, but regarded the conclusion as "quite tentative" given the current limited understanding of paraphilias. Causes
The causes of paraphilias in people are unclear, but some research points to a possible prenatal neurodevelopmental correlation. A 2008 study analyzing the sexual fantasies of 200 heterosexual men by using the Wilson Sex Fantasy Questionnaire exam determined that males with a pronounced degree of fetish interest had a greater number of older brothers, a high 2D:4D digit ratio (which would indicate excessive prenatal estrogen exposure), and an elevated probability of being left-handed, suggesting that disturbed hemispheric brain lateralization may play a role in paraphilic attractions.Behavioral explanations propose that paraphilias are conditioned early in life, during an experience that pairs the paraphilic stimulus with intense sexual arousal. Susan Nolen-Hoeksema suggests that, once established, masturbatory fantasies about the stimulus reinforce and broaden the paraphilic arousal.
In the ICD-8 (1965), “sexual deviations” were categorized as homosexuality, fetishism, pedophilia, transvestism, exhibitionism, voyeurism, sadism and masochism. ICD-9
In the ICD-9 (1975), the category of sexual deviations and disorders was expanded to include transsexualism, sexual dysfunctions, and psychosexual identity disorders. The list contained homosexuality, bestiality, pedophilia, transvestism, exhibitionism, transexualism, Disorders of psychosexual identity, frigidity and impotence, Other sexual deviations and disorders (including fetishism, masochism, and sadism). ICD-10
In the ICD-10 (1990), the category "sexual deviations and disorders" was divided into several subcategories. Paraphilias were placed in subcategory of "sexual preference disorders". The list included fetishism, fetishistic transvestism, exhibitionism, voyeurism, pedophilia, sadomasochism and other disorders of sexual preference (including frotteurism, necrophilia, and zoophilia). Homosexuality was removed from the list, but ego-dystonic sexual orientation was still considered a deviation which was placed in subcategory "psychological and behavioural disorders associated with sexual development and orientation". ICD-11
In the ICD-11 (2022), "paraphilia" has been replaced with "paraphilic disorder". Any paraphilia and any other arousal pattern by itself no longer constitutes a disorder. To date, the diagnosis must meet criteria of paraphilia and one of the following:
1) a marked distress associated with arousal pattern (but not one that comes from rejection or fear of rejection);
2) the person has acted on the arousal pattern towards unwilling others or others considered as unable to give consent;
3) a serious risk of injury or death.