The stages of sexual activity include excitement (arousal), orgasm, and resolution. The precipitating excitement or arousal is psychologically determined. Arousal response leading to orgasm is a physiologic and psychological phenomenon of vasocongestion, a parasympathetic reaction causing erection in men and labial-clitoral congestion in women. The orgasmic response includes emission in men and clonic contractions of the analogous striated perineal muscles of both men and women. Resolution is a gradual return to normal physiologic status.
While the arousal stimuli—vasocongestive and orgasmic responses—constitute a single response in a well-adjusted person, they can be considered as separate stages that can produce different syndromes responding to different treatment procedures.
There are three major groups of sexual disorders.
In these conditions, formerly called “deviations” or “variations,” the excitement stage of sexual activity is associated with sexual objects or orientations different from those usually associated with adult sexual stimulation. The stimulus may be a woman’s shoe, a child, animals, instruments of torture, or incidents of aggression. The pattern of sexual stimulation is usually one that has early psychological roots. When paraphilias are associated with distress, impairment, or risk of harm, they become paraphilic disorders. Some paraphilias or paraphilic disorders include exhibitionism, transvestism, voyeurism, pedophilia, incest, sexual sadism, and sexual masochism.
Exhibitionism is the impulsive behavior of exposing the genitalia to unsuspecting strangers in order to achieve sexual excitation. It is a childhood sexual behavior carried into adult life.
Transvestism consists of recurrent cross-dressing behavior for the purpose of sexual excitation. Such fetishistic behavior can be part of masturbation foreplay.
Voyeurism involves the achievement of sexual arousal by watching the activities of an unsuspecting person, usually in various stages of undress or sexual activity. In both exhibitionism and voyeurism, excitation leads to masturbation as a replacement for sexual activity.
Pedophilia is the use of a child of either sex to achieve sexual arousal and, in many cases, gratification. Contact is frequently oral, with either participant being dominant, but pedophilia includes intercourse of any type. Adults of both sexes engage in this behavior, with exact prevalences unknown, but likely far less common among females.
Incest involves a sexual relationship with a person in the immediate family, most frequently a child. In many ways it is similar to pedophilia (intrafamilial pedophilia). Incestuous feelings are fairly common, but cultural mores are usually sufficiently strong to act as a barrier to the expression of sexual feelings.
Sexual sadism is the attainment of sexual arousal by inflicting pain upon the sexual object. Much sexual activity has aggressive components (eg, biting, scratching). However, forced sexual acquiescence (eg, rape) is an act of aggression.
Sexual masochism is the achievement of erotic pleasure by being humiliated, enslaved, physically bound, and restrained. It may be life-threatening, since neck binding ...