(Part 1: Soft tickling)
At my wedding, one of my groom's vows was a promise to tickle my feet. This was only half-facetious: foot-tickling, for me, has come to be an expression by my loved one(s) of affection and the provision of relief at the end of a long day, much as monkeys groom each other to express intimacy and the desire to take care of each other.
Now, it appears, tickling actually helps to relieve pain, according to a new Swedish study:
"Basically the signals that tell the brain that we are being stroked on the skin have their own direct route to the brain, and are not blocked even if the brain is receiving pain impulses from the same area. In fact it’s more the opposite, that the stroking impulses are able to deaden the pain impulses," says Line Löken, postgraduate student in neurophysiology at the Sahlgrenska Academy.
It seems that we are hardwired for grooming.
Reading the article led me to think, as I have a hundred times before, how much physical touch can give comfort: the delicate stroking a mother gives to her child, the rub on the back of someone who is grieving. Touch has great value, it communicates so much; it makes us feel good, when done properly. Our bodies respond to it.
In more ways than one, it seems. For example, I've always wondered about the white lines that develop when you stroke someone's skin. Have you ever noticed that? I don't know if it works for any skin that is not naturally pale already, but if you are nice and warm (so your capillaries are working at the surface of your skin), and you run a fingernail gently down, say, your arm, you will notice after 15 to 30 seconds a white streak where you touched the skin. I have always wondered what this reaction is.
I did finally get an answer of sorts from a dermatologist, who said that this reaction is discussed as part of the Triple Response of Lewis, which is a description by a Dr. Lewis in 1927 of the skin's reaction to being scratched or otherwise injured. Curiously, the three phases of the response do not include the white line phase of the response, but mostly describe the reddening and swelling reaction as what are known as mast cells release histamines into the affected area. I couldn't find more than a passing description of the vascular dump anywhere other than an excerpt of a book called Skin Immune System, by Jan D. Bos, which came out in 1997.
A light injury does not lead to the triple response. Instead, a "white line" is produced by the emptying of capillaries under the contact site... The reaction lasts 15 minutes and edema does not develop. The response has not been systematically studied because it is difficult to induce reproducibly. The white line response is reminiscent of white dermographism and adrenoceptor mediated blanching.
As far as I can tell, "adrenoceptor mediated blanching" is the kind of blanching we experience when we are stressed - in other words, they are tied into the fight-or-flight reflex, and are associated with the sympathetic nervous system, which is connected to the same response. So when we get hurt or when we are fearful, or are under great emotional upheaval, we get the urge to run away, to save ourselves... and we tend to go paler in those situations.
Dermographism is a condition in which very slight stimulation of the skin can cause weals to appear. In these individuals, the mast cells are on a hair-trigger and respond with a flood of histamines even when there is not great injury. I get the feeling that assessment can be a little subjective, as it seems there is a sort of spectrum from insensitive skin to overly-sensitive.
Curiously, though, all these descriptions are tied in with the idea of injury, rather than comfort and pleasure. So what is it that makes having one's feet tickled so pleasurable?
Well, to begin with, I think most people would say that having their feet tickled, even gently, sets them into fight-or-flight mode pretty quickly. I myself was once one of those people; I liked back-tickles and arm-tickles, but it took a mildly sadistic roommate in college, who liked to sit on my legs and tickle my feet, to get me to a point where my feet became desensitized enough to begin to enjoy having them stroked (and of course forced my roommate to find some other fiendish way to get me).
Once the desensitization had kicked in I began to find that tickling my feet, after a long day of walking and standing in hot shoes, actually helped cool them down, made them stop hurting and decreased the swelling significantly. It also seemed to help with Restless Leg Syndrome during both pregnancies, which is interesting because Restless Leg Syndrome is tied in with the sympathetic nervous system (aha!) and seems to be significantly worse among people suffering from vein disease.
I spoke by email to Ms. Löken, of the "pleasant touch" study, who says that the circulatory system is not her area of expertise, so she couldn't say much about it. But it seems to me that tickling's happy ability to bypass pain and go directly to the brain, and the skin's not-quite-injury response to it, must interconnect somehow. What if the blanching isn't related to injury, but to some other purpose? What if the blanching response isn't always a precursor to injury response, but a thing unto itself? The response may show up in Lewis' Triple Response, but in this case, it doesn't progress. And I wonder if pain is the only thing tickling affects? Could it be a new answer to some minor health issues? Perhaps it is the new acupuncture, and we will soon see Tickle Clinics springing up everywhere.
Now that would be a thing worth seeing.
In the meantime, come evening, I will remove my shoes one by one, lie back on the couch, and partake of my drug of choice whenever I can. Hail to the Tickler!
Next: The Other Kind of Tickle
Addendum: It seems that I got into realms I hadn't dreamed of. Ah, the naivete! Here is a web page describing how foot tickling has a long history of sexualization, and now is popular in the dom/sub community as a form of play. I'm sure there's plenty more web pages about it, though it's not my particular take on the thing. Knock me over with a feather!