Hacking sexual pleasure: a hard, slippery problem
3001: A Pants Odyssey
NSFW Everyone wants more pleasure with less effort, so humans have used mechanical augmentation for ages: prehistoric dildos and porn, Kama Sutra treatises, lubes, piercings, and lately vibrators and Viagra. But since sex is really all about electrical nerve impulses, shouldn't electronics and signal processing be able to enhance pleasure even further? Can't we geeks contribute technology to our favorite activity?
Unfortunately, technical types often ask "What can we do with our cool tech?", rather than "How and why does sex feel good?" For example, recent meetings on sex technology (SXSW  and Sex Hacks ) show a burgeoning interest in hooking up vibrators to iPods, microphones, cellphones, and video games. New inputs, but the same old transducers. So how about starting with the basics of sex instead?
Sex is complicated. Desire, engorgement, lubrication. So many sensations: teasing, urgency, incipient climax, contraction, affectionate pair-bonding, sleepiness. And half a dozen hormones or neurotransmitters - testosterone, dopamine, oxytocin, vasopressin, prolactin - both create and respond to sensations and expectations in myriad positive and negative feedback loops. Several different nerve pathways are involved: in the woman, the majority of nerves are in the clitoral head (not the vagina), while the "G-spot" is really the backside of the clitoris. The sciatic nerve is nearby, and an unrelated non-spinal nerve (the vagus) seems involved; at least one woman with a severed spinal cord was still able to orgasm.
Vascular dynamics and anatomy aside, science hasn't been much help. Recent MRI images of sex really just show the shape of the interlocking genitals, nothing more. The only way to "measure" sensation is to ask people what it feels like. Even the basics aren't so basic; in both men and women, orgasmic sensation can sometimes occur without contractions or ejaculation, and vice versa. Such exceptions matter, because "hacking" cares more about how a system can work than how it was designed to work. In this context, having fun and "getting off" aren't necessarily the same thing.
Why can't a woman be more like a man?
For most men, it's enough to have porn, lubrication and a towel; further gadgets are optional. Men comprise most of the hackers and tinkerers, while the sex-toy users are mostly women (at least to judge by the gadgets for sale). But women respond very differently from men.
Take Viagra, for example. Viagra creates the same engorgement in women as it does in men, but in general women don't enjoy the sensation; drug-maker Pfizer is reluctantly abandoning its years-long research on "female Viagra" for want of success, despite a huge potential market.
Women's disconnect between crotch and head can be even greater: recent research shows women can be consciously turned off ("Ick!") at the very same time they're physically turned on. Almost no one - let alone geeky tinkerers - really understands how pleasure works, much less how to hack it. Even the basic physical interface from signal to skin hasn't improved in ages.
How does skin work? Tactile sensations are transmitted by thousands of strain- , pressure- , and vibration-sensitive neurons layered throughout the skin and erogenous tissue: different combinations of neural responses - i.e. different distributions and synchrony of signals - convey sensations of pressure, heat, stroking, slippery, rough, and so on. Only a handful of the "right" neural patterns correspond to real-world stimuli, just like only certain pixel patterns represent real images on a TV.
So even if we could somehow trigger all the neurons individually, it would still be nearly impossible to simulate a realistic physical sensation. Injecting raw electricity through the skin - "electro-stim" - can fire neurons but can't fool them into creating the right patterns, any more than flashbulbs or white-noise can simulate a TV picture. So raw electricity will always feel, well, electrical. (There is one possible exception: a product, called Slightest Touch , claims to transmit imperceptible levels of electricity through pleasure centers of the pelvis, creating pleasure without any uncomfortable "electrical" buzz. A great idea, if it works).
The necessarily weird feelings of electro-stim are usually used to produce novelty or pain (as a recent demo  suggests) rather than pleasure. A much better way to transform electricity into touch is the vibrator, which was invented about a century ago (see the Antique Vibrator Museum ), and hasn't changed too much since: typically, a weighted electric motor spins and shakes, just like in a cellphone. This is a compact and efficient way to convert electricity into motion, but the shaking is still just shaking. At best one can vary the speed of the motor, say by cleverly processing an audio signal to become drive-current.
Simple shaking can be fun - women routinely use their Rabbit vibes to destruction, month after month - but a vibrator isn't much more sophisticated than raw electricity, since it has the simplest possible motion: back and forth at a single frequency. Neurologically, that's pretty predictable and boring. So the most popular vibes are built into dildos, allowing the basic buzz to be modulated by manual dexterity (position, angle, pressure, and motion); the human touch still counts for much of the success.
Is there a path to improving vibe-like stimulation? Maybe, at least if tinkerers can be more creative.
For example, the single-point, single-frequency shaking of a vibrator might be replaced by a closely-spaced matrix of gentle activators (like a Braille touch-pad). A set of wave-like input signals on the grid could simulate motion (side-to-side? circular?); synchronous inputs could simulate tapping or pulsing. Even random signals might have a pleasant effect. It is already an open secret that the near-random, quickly-varying turbulence of a gentle stream of water can be far more physically exciting than a constant, regular buzzing (water is a famous female masturbation trick).
Could that sensation be simulated by a toy? It would be difficult, because synthesizing high-frequency random motions is a mechanical challenge, and distributing them in patterns across a centimeter of skin would be harder.
Even the ultimate mechanical transducer could not have the subtlety and sensitivity of a human fingertip, much less a mouth. Imagine the technical specification: a highly flexible, self-articulated annular pressure zone ("lips"), multi-joint articulated "tongue," highly variable suction, and self-lubrication. Not to mention sensors, with built-in adaptive signal-processing, to detect not only the skin they touch but the effect on the owner. And really, really good driver algorithms.
Trying to reduce pleasure-generation to simple mechanics and signal-processing is geeky and - worse - wrong. Pleasure is as much about psychology and anticipation as it is about simple mechanical signals. Sometimes a signal which is hard to anticipate (like a random or human-driven one) is more exciting than a something regular. And intense isn't always better; gentle sensations, especially in sensitive areas, can further heighten sensitivity (tickling, for example).
Perception is a mental process; as with yoga and meditation, persistent focus on a sensation can matter as much as the stimulus.
Hacking without technology
One group is pushing the "hack sex" principle to its limit without any technology at all. A so-called "sensual community" in San Francisco, based around The OneTaste Urban Retreat Center , has a yoga-like practice of "Orgasmic Meditation" involving long periods of gentle clitoral stroking, a sort of prolonged genital tease (the group is run by women, so don't blame men for that apparently frustrating discipline).
Perhaps it's the women's influence which also makes them place such heavy emphasis on the psycho-dynamics of giving and receiving sensual pleasure; they hack the social and psychological aspects of sex too.
Women's sexual responses, especially, are constrained by communication and expectation: unspoken assumptions and anxieties can crowd out and suppress the actual, physical sensation. For example, expectations about having to "put out" can dampen enjoyment of foreplay; alternatively, one partner may feel obliged to induce an orgasm, the other may feel obliged to reach or fake it, and both can end up feeling disappointed or inadequate.
Professionals who actually know and teach about sex - therapists and coaches, for example - are unanimous that communication and trust is far more important than mechanical technique. Yet there is no consensus on what pleasure really is.
Some people want to "get off" quickly, while some want to prolong the intense feeling of incipient orgasm. Some want control of the stimulation, some want reckless abandon, some want to be actively dominated, some want to dominate. Some want a connection to another person, some want raw solo sensation. And some want each of these at different times.
So no amount of new electro-mechanical technology is likely to make up for understanding how sex works and how our minds create and appreciate it. Of course, if there is an effective new way of turning people on - a new drug or futuristic Orgasmatron  - some fanatic tinkerer will doubtless stumble across the principle, create a prototype, and market it.
If it really works, we'll all know soon enough.®
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