• Mystery of the G-Spot by Dr Jack Lewis

    In this month’s blog I’m going to take you on a whistle-stop tour of the female orgasm. Every woman is wired up slightly differently, so for the avoidance of doubt please remember that this article is just designed as a primer, merely to open people’s eyes to some sensory structures they might not be entirely aware of, and to showcase some of the additional variety of orgasmic options women have available to them compared to men, generally speaking. I don’t claim to be an expert on sex biology, just a keen amateur…

    The G-spot was named in honour of the gynaecologist Ernst Graefenberg M.D., who first proposed the presence of an “erotogenic zone” (an area of tissue that swells and evokes erotic sensations in response to touch) just inside the vagina alongside the urethra, in a paper published in 1950. Despite the testimony of thousands (millions?) of women that a particularly sensitive region of the vagina resides at this location, its existence is still contested in the medical literature. How can this be?

    About a decade ago, an academic paper was published claiming to have finally confirmed the existence of the fabled G-spot (on the basis of a post-mortem dissection of a 83 year old cadaver). The author was promptly pounced upon by colleagues with numerous objections. The dispute continues to bubble with medics and scientists continuing their debate over whether or not a distinct anatomical structure exists close to the opening of the vagina in its anterior wall (that is: the front-facing part).

    Stimulation of the clitoris – or the glans clitoral to be specific – nestling directly beneath a hood of tissue protecting this often extraordinarily sensitive sensory structure – is regarded to an effective way of stimulating the female genitalia in the pursuit of orgasm in many but not all women. Effective as this may be for many women in reaching climax efficiently, the orgasm that results tends to be highly localised to the immediate vicinity of the clitoris itself. Vaginal stimulation, on the other hand, can result in an orgasm that manifests itself throughout the entire body.

    Taking a closer look at the illustration above, the glans is clearly just the tip of the clitoral iceberg. It also extends to incorporate both the left and right crus clitoris (dark pink) and the bulb of the clitoral vestibule (light pink). Considering the close proximity of the bulb of the clitoral vestibule to the anterior (upper, in this diagram) wall of the vagina – it is clear to see why pressure upon this region (location of the highly contested G-spot) is thought by many experts in the field to actually mediate its effects via stimulation of the clitoral bulbs. The paraurethral glands (a.k.a. Skene’s glands or female prostate) are also unavoidably stimulated by this same pressure and from which an ejaculatory fluid may be expelled at climax in some women.

    Orgasms resulting from stimulation of the vagina tend to involve muscular tension that gradually builds up throughout the whole body, culminating in an intense euphoria and muscular convulsions that cause involuntary spasms in the limbs, torso and face at the moment of climax.

    Yet another different type of orgasm altogether can be elicited by stimulation of the cervix; the “neck” of the womb or uterus which lies at the far end of the vagina and has its very own system of nerve fibres carrying touch information to the brain. Touch information is relayed to the somatosensory cortex –  a strip of brain tissue dedicated to processing tactile sensation from all over the surface of the human body. Although the different brain areas dedicated to processing touch at the tongue/mouth/throat, face, hand, arm and trunk are located in a strip on the outer surface of the brain, those that receive tactile information at the leg, foot and toes are positioned on the part of this strip that spills over onto the inner surface of the brain where the two hemispheres face each other.

    Just below the area dedicated to processing tactile sensations in the toes are three separate but overlapping areas that produce the sense of touch at the clitoris, vagina and cervix.

    Stimulation of the clitoris is primarily carried to the brain via the pudendal nerve, vaginal stimulation mainly by the pelvic nerve and cervical stimulation mainly by the hypogastric, pelvic and vagus nerves. Simultaneous stimulation of the clitoris, vagina and cervix can result in a “blended” orgasm incorporating the various qualities of each.

    If you found this interesting and are interested in doing some further reading, I’d highly recommend the “Science of Orgasm” by Komisaruk, Beyer-Flores and Whipple.

    In addition to these monthly brain blogs, I also flag brain-related articles on Twitter.

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