Experienced by males and females, orgasm is controlled by the involuntary, or autonomic, limbic system, and is accompanied by quick cycles of muscle contraction in the lower pelvic muscles, which surround the primary sexual organs and the anus. Orgasms are often associated with other involuntary actions, including muscular spasms in multiple areas of the body, a general euphoric sensation and, frequently, body movements and vocalizations are expressed. In males, orgasm generally leads to ejaculation.
Orgasm is an autonomic physiologic response to sexual stimulation. Brain wave patterns have shown distinct changes during orgasm, which indicate the importance of the limbic system in the orgasmic response. In humans, orgasms usually result from the stimulation of the penis in males and the clitoris in females. Stimulation can be by self-practice (masturbation) or by a partner (penetrative sexual intercourse, non-penetrative sex; also known as outercourse, and other erotic sexual activities). In addition, partners simultaneously stimulating each other's sex organs by mutual masturbation, penetrative intercourse, or other rhythmic inter-genital contact may experience simultaneous orgasms.
The period after orgasm (known as a refractory period) is often a relaxing experience, attributed to the release of the neurohormones oxytocin and prolactin. Male and female brains demonstrate similar changes during orgasm (by partner controlled orgasm), with brain activity scans showing a temporary decrease in the metabolic activity of large parts of the cerebral cortex with normal or increased metabolic activity in the limbic areas of the brain.