Both men and women can have “wet dreams” and “morning wood.” While nocturnal emissions and arousal are much more noticeable in men than women, both genders experience this common phenomenon. Although this topic may be awkward to think or talk about, this is a perfectly normal experience for sexually healthy young people.

Patrick Carter is a biology professor at WSU who teaches human physiology. Carter said that some people, especially young men, may not be aware that women also experience the female version of a wet dream, as well as the equivalent of morning wood.

Sexual arousal and orgasm, even during sleep, is simply a normal response of the human nervous system.

Arousal is a very complex reaction within the human body. The automatic nervous system has two parts, the parasympathetic nervous system, which is active during normal activity such as digestion, and the sympathetic nervous system, which activates during “fight or flight” responses. Usually these two parts do not contribute at the same time, however during sex this is different.

“One of the really cool things about sex is [that the sympathetic and parasympathetic nervous systems] work together,” Carter said.

During arousal, physical stimulation leads to a response by the parasympathetic nervous system. This causes more blood to flow to the penis in men and the clitoris and vagina in women. When a person orgasms, however, the sympathetic nervous system takes over.

Both of these responses are automatic in the sense that you don’t necessarily need to be conscious for them to take place, although the brain can either diminish or enhance the sexual response. But when a person is asleep, arousal can happen without them even being aware.

Nocturnal emissions are fairly common during the early stages of sexual development, Carter said. But while wet dreams often peak during early puberty and decrease as a person gets older, “morning wood” is common among adults of all ages, and is a sign of good sexual health.

“Most sexually healthy men have erections during sleep,” Carter said.

As awkward as “morning wood” is, it is in the end a natural part of your body’s systems working. In fact, if a man does not have nocturnal erections, it may be a sign of erectile dysfunction, Carter said.

Carter said that although these topics can seem embarrassing, people will be more understanding and less awkward about them when they understand the science behind it.