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Mrs. A was a 55-year-old woman living in the Netherlands who began experiencing a strange and embarrassing problem in 2010: Five to six times a day, she felt as if she was having an orgasm … in her left foot. As in, it felt just the same as an orgasm that happened during sex would, only the sensation began in her foot. In a 2013 report published in The Journal of Sexual Medicine, her medical team discusses her condition, which they say is the first recorded case of something they straightforwardly dub “foot orgasm syndrome.”

The Patient: In late 2008, Mrs. A contracted a sepsis infection and spent three weeks in an intensive-care unit. During her hospital stay, she slipped into a coma. When she regained consciousness, she started feeling some odd sensations in her foot — “tingling, burning feelings,” is how she described it to her medical team, including Dr. Marcel D. Waldinger, then a neuropsychiatrist at Utrecht University. (He’s since become an adjunct professor at Drexel University in Philadelphia.) It was a preview, it seems, of things to come.

The Problem: A year and a half after that hospitalization, the foot orgasms started. When she first sought medical treatment for the problem, she was so embarrassed by her situation that she cried while discussing it with the physicians, and “was hardly able to talk about her complaints,” Waldinger and his co-authors write. She eventually told them the details of what she was experiencing, which they describe in their paper as “a real orgasm in her left foot, similar to a vaginal/clitoral orgasm but of shorter duration.” She also told her doctors that it felt like the sensation was “running from her left foot via her left calf to her vagina, and her head.”

More on that, as Waldinger and his co-authors write in their case report:

These unwanted sensations felt like a real orgasm, of short duration (about 5-6 seconds), in absence of sexual desire or sexual thoughts … The experience of this induced orgasmic sensation originating in the left foot was of the same orgasmic quality as what Mrs. A experienced when having an orgasm induced by sexual intercourse with her husband. Moreover, when making love to her husband, Mrs. A experienced a vaginal/clitoral orgasm which was immediately followed by the same orgasmic sensation in her left foot.

The Diagnosis: The most likely explanation, Waldinger and his colleagues write, is that Mrs. A suffered damage to the nerve fibers in her left foot during her bout with sepsis. Also, it just so happens that the nerves of the foot, labia, clitoris, and vagina are all served by the same part of the spinal cord, the S1-S4 segments. The foot orgasms began as the nerve damage in her foot started to heal, which suggests that the strange sensations may be explained by some confusion among those nerves — some crossed wires, essentially. As Waldinger told LiveScience in 2013, “the brain could not anymore differentiate between the foot and the vagina. So … it decided that every stimulus coming from the foot was actually coming from the vagina.” This means, he further explained in an email to Science of Us, that a nerve stimulus from her left foot was “translated” by the brain as an orgasm.

It worked out okay for Mrs. A, however: After an injection of anesthesia into one of those spinal-cord segments that serves the foot, the foot orgasms stopped. (Though she remained able to experience vaginal and clitoral orgasms, Waldinger said.) Speaking more generally, the nervous-system link between the feet and the genitals is interesting, as it may help explain a fairly common sexual predilection: the foot fetish. In 2007, for example, a team of Italian and Swedish sex researchers took a dive into message boards where people discussed their fetishes. Feet were the most common fetish they uncovered in their research. But not just feet — “objects associated with feet,” such as toes, socks, and shoes had their share of fans, too.

This is something the neuroscientist V.S. Ramachandran explored in his 1999 book, Phantoms in the Brain: Probing the Mysteries of the Human Mind, in which he also uses the physiological proximity of the nerves that serve the feet and the genitals as an explanation for the relative commonality of the fetish. Waldinger cautions that this is only a theory – however, since the publication of the case report, he also told Science of Us that he has received emails from men and women around the world who say they have experienced orgasms that started with manual manipulations of one or both feet. As Ramachandran wrote in his book, “Maybe even many of us so-called normal people have a bit of cross-wiring which would explain why we like to have our toes sucked.”