I am fast asleep when I begin to have a sex dream that feels unusually real. The dream progresses, and suddenly, I feel a rush of pleasure throughout my body. I wake up and think, I orgasmed in my sleep! Did I orgasm in my sleep? Is that even possible?
Turns out—yes, yes, and yes. Sleep orgasms are completely real. "There’s an actual physical orgasm,” said Madeleine Castellanos, a psychiatrist and sex therapist practicing in New York City. “Most people, when they wake up, will remember having an erotic dream," she said. Yet while men will have physical evidence of an orgasm (yes, male sleep orgasms are better known as "wet dreams"), women will have only the memory.
Which is why, for women, sleep orgasms can be confusing. There’s no proof they happen, so many women wonder: Was it just a dream, or did my body really climax? As Castellanos explained to Fusion, despite our bodies being in a "paralyzed" state during rapid eye movement (or REM) sleep—when sleep orgasms are most likely to occur—the brain is technically still on and can feel an orgasm.
For women, the "proof" is internal. Back in 1983, researchers measured the physiological changes that occurred when a woman orgasmed in her sleep, and they found that her heart rate sped up from 50 to 100 beats per minute and her breathing from 12 to 22 breaths per minute—and she experienced a "very marked" increase in vaginal blood flow.
Then there's the brain activity. While the 1983 study is one of the few to measure orgasm during sleep, Barry Komisaruk, a distinguished professor at Rutgers University, has studied "non-genital orgasms" extensively, including women who can "think" themselves to orgasm. His work mapping what happens in the brain during these orgasms helps explain how one can climax while unconscious.
When we orgasm, our brains light up. “All the major brain systems become activated during orgasm,” said Komisaruk, like “a storm in the brain.” This is why men and women report having out of body experiences or entering into altered states of consciousness during orgasm—at no other time is the brain activated all at once like it is during sexual climax.
This makes sense when we're in the throes of sexual passion, but what triggers this neurological "storm" when we’re fast asleep—and no one is actually touching us?
“During REM sleep you have increased blood flow to your erectile tissue—for women it’s in the whole clitoral complex," said Castellanos. "Your brain recognizes that you have more blood flow in those tissues, and it can lead to sexual arousal."
So blood flow leads to arousal—but how do we go from arousal to climax? This is where Komisaruk’s work offers some insight. He and his colleagues enlisted 10 women who claimed they could "think themselves" to orgasm to participate in a study that measured what happened in the brain during genital versus non-genital stimulation.
“We asked the women to have both orgasms—physical and mental,” Komisaruk told Fusion. “We measured what was happening during both, and the magnitude of the responses was about the same regardless of whether it was self-stimulation or just mental.”
In other words, the women's brains reacted nearly identically whether they physically masturbated or "thought themselves" to orgasm—and in both cases, they experienced a significant increase in systolic blood pressure, heart rate, pupil diameter, and pain tolerance. But how?
Komisaruk says he and his team observed one major neurological difference between the two scenarios that may help explain how the brain orgasmed without stimulation: During the mental orgasm, they saw increased activation in the prefrontal cortex—the part of our brain responsible for cognitive behavior, or thinking.
Here’s why that’s important—bear with us as we get a little technical.
This neurological explanation also involves another part of your brain called the sensory cortex, which contains a map-like representation of your body. So, for example, when you touch your hand, the part of the sensory cortex that represents your hand "lights up." When you touch your face, the area for face on the sensory cortex "lights up." Similarly, if you touch your clitoris, the clitoris region on the sensory cortex "lights up." You get the idea.
So when the women were asked to think themselves to orgasm—and think about touching their clitoris—the clitoral map region on the sensory cortex was activated, as if they were actually touching it. Komisaruk and his colleague Nan Wise were able to observe this activity first-hand using a functional MRI machine.
“What we found, to my great surprise, is that when [the women] thought about stimulation of a body region, the corresponding region of the sensory cortex map was activated as if they were physically stimulating that body region,” said Komisaruk.
“But there was a much greater activation in the prefrontal cortex," he continued, "when the women thought about stimulating a particular body region than when they actually physically stimulated that body region.”
This observation may help explain why one can go from arousal to orgasm during sleep. In the same way that stimulating sexual organs when you're awake can lead to orgasm, so can it when you're out cold—especially given that the genitals are already aroused during REM sleep.
Then there are the women who can't orgasm in "real life" but can in their sleep, said Castellanos, who is also the author of the book Wanting to Want: What Kills Your Sex Life.
And there’s a logical explanation for this disparity, she said: “Think about it, when you have a sex dream, the brain is creating an environment to get to the full level of arousal, and you don’t have to be anxious or distracted. It’s all based on eroticism. So sometimes it might be easier to reach orgasm in your dream than in real life.”
It’s no secret that, for women, orgasming involves the mental as much as the physical. If a woman feels uncomfortable during sex for any reason, it’s difficult to climax. However, in her dreams, there’s no discomfort—just pure, unadulterated fun.
Which is why Castellanos believes sleep orgasms can be valuable in understanding the role of the mind in sexual desire and fulfillment. When we "think about sex positively," she said, "it really enhances our pleasure, and shows that if our minds aren't involved in the process, we really shortchange ourselves.”
Taryn Hillin is Fusion's love and sex writer, with a large focus on the science of relationships. She also loves dogs, Bourbon barrel-aged beers and popcorn — not necessarily in that order.