Imagine you're playing a video game, reading a book, maybe taking a hike in the woods, basically minding your own business when the orgasm arrives. No arousal, no physical stimulation, no buildup, no control: just an instantaneous shift from normal status quo into woaaah.
That can be a regular event in the lives of people with a rare version of epilepsy -- their seizures start with an orgasm.
It doesn't mean it's fun. Although a few patients have reported enjoying their seizures, many felt that the lack of control over where or when they orgasmed was unpleasant, embarrassing or frightening, which was probably why they sought treatment and wound up as medical case studies. And many of the cases have a remarkable point of similarity: when doctors measured the brain activity of patients that felt orgasmic but showed no outward sign of physical arousal, they found concentrated activity in one of the patient's temporal lobes early in the seizure, most commonly on the right side of the brain. In a few patients, the temporal seizure was triggered by a specific activity -- in one now-famous case, one woman's orgasmic seizures were triggered by toothbrushing. She thought she was possessed by a demon.
Orgasmic seizures are certainly a nifty bit of cocktail-party trivia -- but these cases can also give us clues to how the brain controls orgasm. Because like pretty much every other aspect of our bodies' behaviour, the brain is directing the show. But pinpointing the circuits that are important to specific aspects of the orgasm experience is hard, because during a typical orgasm brain activity spikes all over the place.
That's not surprising if you think about it. For most people, getting to orgasm involves a lot of activity. And that activity is going to activate parts of the brain that aren't specifically responsible for the way it all feels: the motor cortex and cerebellum are busy controlling moving fingers and clenching muscles, the areas responsible for processing genital pressure and touch are firing like mad, visual systems activate to process how sexy a partner looks, or even to remember how sexy a partner looked. You get the picture. Neuroscientists can (and have) imaged people's brains during orgasm, but the data they get back paints a big, holistic picture of the orgasm. The specific part that each active region plays in the experience is still unknown.
The effects of orgasmic seizures hint that the specific feeling of warmth and release that comes packaged with an orgasm is managed inside the temporal lobe. They suggest that those circuits are different from the ones that control sexual movements, since the seizures didn't induce erections or vaginal contractions (another type of seizure, focused in the parietal lobe, can produce painful physical signs of orgasm, including ejaculation). They also suggest that the neurons in charge of producing that feeling of 'reward' or 'liking' are going to be distinct from the ones that manage sexual motivation or 'wanting' -- so the patients can get the reward, but feel distressed because it wasn't anticipated or desired.
Our sexual circuitry is complex and multi-layered, and we're still taking baby steps toward understanding how it works. But if we can someday tease out all the details of the orgasmic cascade inside the brain, we could help people who've lost genital sensation regain their sex lives. Or build an Orgasmatron. Which is more likely?
Top image from Sleeper, MGM