During sleep, sexually mature men and many sexually mature women have from time to time involuntary sexual orgasms;[42] these occur chiefly in persons without opportunities for sexual intercourse, who do not practise masturbation. In such involuntary orgasms the male ejaculates semen, the female indifferent glandular secretions. As a rule, the ejaculation is accompanied not merely by a voluptuous sensation, but also by a psychical process corresponding with the mode of sexual sensibility of the person concerned. A normal man during the orgasm dreams that he is embracing a woman; a normal woman that she is embracing a man; a homosexual man dreams of the embraces of another man. The dream-ejaculation is distinguished from the waking act of intercourse to this extent, that in the former the ejaculation usually takes place during the preparatory stages to the act of intercourse--during kissing, physical contact, or the embrace--so that the dream stops short of complete sexual intercourse. But in other respects the dream ordinarily corresponds to the psychical processes of the waking state. The same correspondence exists as regards sexual dreams that do not culminate in ejaculation. Children also experience sexual dreams either with or without orgasm. In those who have never masturbated in the waking state, a sexual dream is commonly the cause of the first experience of ejaculation; and this occurs more often than is generally believed. More especially in the female sex I have come across many cases in which the orgasm made a primary appearance during sleep. In both sexes alike it is usual for psychosexual phenomena to manifest themselves before the erotic dream makes its appearance; a boy, for instance, will during his waking life have felt an attraction towards members of the other sex before he has begun to dream of embracing a girl. We must not, however, forget that, apart from those cases in which a dream beyond question first unveils to consciousness the psychosexual life, dreams are forgotten very rapidly indeed, especially when the memory is not stimulated by so vivid an occurrence as the sexual orgasm. Hence, even though it is true that the psychosexual life commonly appears to begin during the waking state, we must admit that it is quite likely that psychosexual dreams may have previously occurred and have been forgotten. Thus, in many individuals, sexual perversions make their first appearance in dreams. It has even been suggested that dreams may exercise a similar influence to that of post-hypnotic suggestion; that is to say, that a dream may be the actual originating cause of sexual perversion. This is a matter which I cannot discuss further, more especially in view of the fact that the whole idea is too hypothetical.