The Science of Orgasms
(I was fascinated by the very brief part on Oxytocin — 1:25 — see below)
Subsequent and multiple orgasms
In contrast to the two-stage model of male orgasm, Kahn (1939) equalized orgasm and ejaculation and stated that several orgasms can occur and that “indeed, some men are capable of following [an orgasm] up with a third and a fourth” orgasm.Though it is rare for men to achieve multiple orgasms, Kahn’s assertion that some men are capable of achieving them is supported by men who have reported having multiple, consecutive orgasms, particularly without ejaculation. Males who experience dry orgasms can often produce multiple orgasms, as the refractory period is reduced. Some men are able to masturbate for hours at a time, achieving orgasm many times. Many men who began masturbation or other sexual activity prior to puberty report having been able to achieve multiple non-ejaculatory orgasms. Some evidence indicates that orgasms of men before puberty are qualitatively similar to the “normal” female experience of orgasm, as they do not ejaculate and therefore have no refractory period, suggesting that hormonal changes during puberty have a strong influence on the character of male orgasm.
An increased infusion of the hormone oxytocin during ejaculation is believed to be chiefly responsible for the refractory period, and the amount by which oxytocin is increased may affect the length of each refractory period. Another chemical which is considered to be responsible for the male refractory period is prolactin, which represses dopamine, which is responsible for sexual arousal. Because of this, there is currently an experimental interest in drugs which inhibit prolactin, such as cabergoline (also known as Cabeser, or Dostinex). Anecdotal reports on cabergoline suggest it may be able to eliminate the refractory period altogether, allowing men to experience multiple ejaculatory orgasms in rapid succession. At least one scientific study supports these claims,although cabergoline is a hormone-altering drug and has many potential side effects. It has not been approved for treating sexual dysfunction.Another possible reason for the lack or absence of a refractory period in men may be an increased infusion of the hormone oxytocin. It is believed that the amount by which oxytocin is increased may affect the length of each refractory period. A scientific study to successfully document natural, fully ejaculatory, multiple orgasms in an adult man was conducted at Rutgers University in 1995. During the study, six fully ejaculatory orgasms were experienced in 36 minutes, with no apparent refractory period.Later, P. Haake et al. observed a single male individual producing multiple orgasms without elevated prolactin response.