Orgasm

Orgasm (from Greek ὀργασμός, orgasmos; "excitement, swelling"), sexual climax, or simply climax, is the sudden release of accumulated sexual excitement during the sexual response cycle, characterized by intense sexual pleasure resulting in rhythmic, involuntary muscular contractions in the pelvic region. Orgasms are controlled by the involuntary or autonomic nervous system and are experienced by both males and females; the body's response includes muscular spasms (in multiple areas), a general euphoric sensation, and, frequently, body movements and vocalizations. The period after orgasm (known as the resolution phase) is typically a relaxing experience after the release of the neurohormones oxytocin and prolactin, as well as endorphins (or "endogenous morphine").

Human orgasms usually result from physical sexual stimulation of the penis in males (typically accompanied by ejaculation) and of the clitoris (and vagina) in females. Sexual stimulation can be by masturbation or with a sexual partner (penetrative sex, non-penetrative sex, or other sexual activity). Physical stimulation is not a requisite, as it is possible to reach orgasm through psychological means. Getting to orgasm may be difficult without a suitable psychological state. During sleep, a sex dream can trigger an orgasm and the release of sexual fluids (nocturnal emission).

The health effects surrounding the human orgasm are diverse. There are many physiological responses during sexual activity, including a relaxed state, as well as changes in the central nervous system, such as a temporary decrease in the metabolic activity of large parts of the cerebral cortex while there is no change or increased metabolic activity in the limbic (i.e., "bordering") areas of the brain. There are sexual dysfunctions involving orgasm, such as anorgasmia.

Depending on culture, reaching orgasm (and the frequency or consistency of doing so) is either important or irrelevant for satisfaction in a sexual relationship, and theories about the biological and evolutionary functions of orgasm differ.