It’s all about nerve signals, dopamine and oxytocin…well…not all about that! From the Wiki entry: Orgasm is the sudden release of accumulated sexual tension during the sexual response cycle involving an intense sensation of pleasure. It is experienced by males and females and is controlled by the autonomic nervous system. The period following orgasm (the refractory period) is often a relaxing experience, attributed to the release of the neurohormones oxytocin and prolactin.