Portions of this fall under the "too much information" advisory, but it's interesting, nonetheless;
Unlike, say, the nerve fibres for pain, each of which covers a millimetre-size territory, a single itch fibre can pick up an itchy sensation more than three inches away. The fibres also turned out to have extraordinarily low conduction speeds, which explained why itchiness is so slow to build and so slow to subside.Other researchers traced these fibres to the spinal cord and all the way to the brain. Examining functional PET-scan studies in healthy human subjects who had been given mosquito-bite-like histamine injections, they found a distinct signature of itch activity. Several specific areas of the brain light up: the part of the cortex that tells you where on your body the sensation occurs; the region that governs your emotional responses, reflecting the disagreeable nature of itch; and the limbic and motor areas that process irresistible urges (such as the urge to use drugs, among the addicted, or to overeat, among the obese), reflecting the ferocious impulse to scratch.
Now various phenomena became clear. Itch, it turns out, is indeed inseparable from the desire to scratch. It can be triggered chemically (by the saliva injected when a mosquito bites, say) or mechanically (from the mosquito’s legs, even before it bites). The itch-scratch reflex activates higher levels of your brain than the spinal-cord-level reflex that makes you pull your hand away from a flame. Brain scans also show that scratching diminishes activity in brain areas associated with unpleasant sensations.
But some basic features of itch remained unexplained—features that make itch a uniquely revealing case study. On the one hand, our bodies are studded with receptors for itch, as they are with receptors for touch, pain, and other sensations; this provides an alarm system for harm and allows us to safely navigate the world. But why does a feather brushed across the skin sometimes itch and at other times tickle? (Tickling has a social component: you can make yourself itch, but only another person can tickle you.) And, even more puzzling, how is it that you can make yourself itchy just by thinking about it?
test
Posted by: Orlin at July 10, 2008 1:28 PMThinking about Liberals, Democrats, Socialism, AGW, carbon tax, 'The' Green Shift, and pacifists also makes me itch.
Posted by: PhilM at July 10, 2008 1:28 PMThe MSM make me itch. All the front pages of our newspapers have the faked Iran missile photo. Makes my skin crawl.
Posted by: Gunney99 at July 10, 2008 1:38 PMOk, so how many of us read this and noticed an itch almost immediately?
;)
Posted by: AtlanticJim at July 10, 2008 1:41 PMWhy is it that whenever both your hands are totally occupied and can be used for no other task does your nose begin to itch?
Posted by: a different Bob at July 10, 2008 1:53 PMOr a diff.bob....why is it (in men) the your testicles itch only when in public??
Posted by: Justthinkin at July 10, 2008 2:07 PMCan we dump a big pile of itch over Iran?
Posted by: Sounder at July 10, 2008 2:12 PMI'm just surprised that something from the New Yorker made it here. Although their left-wing commentary still drives me nuts, I continue to read it for the quality of their articles, fiction, and, of course, cartoons.
I also found it interesting that, during the Democratic primary, they couldn't find it within themselves to support the - you should forgive the double oxymoron - "native son" Hillary. What I now find amusing is the tortuous logic they use to approve of Obama's flip-flops on public election finance, withdrawal from Iraq, etc.
Posted by: KevinB at July 10, 2008 2:14 PMDon't know what the purpose of this is, but I did say a brief prayer of thanks.
I had long-lasting painful itch after a bout of shingles and mine was in a disagreeable place also.
Wouldn't wish it on my worst enemy.
Adults, beware kiddies coming down with chicken pox if you haven't had it yourself.
funny thing....all MY itches last around seven years.
Posted by: john begley at July 10, 2008 2:59 PMWhat was that question regarding itches ... in the old standard idiot test? .....
I have an itch to see every HRC in this Nation ground to political dust as the illegal political courts they are.
I would say itching is a needed component of social bonding, Most Cultures have very elaborate grooming rituals both private & personnel for societal integration. Young girls like to braid each others hair as an example, in Africa people pick lice from each other.
I have noticed as well that when I have had an injury, the affected area when it begins to heal itches terribly. Even when I was almost ham strung with 2 years for the nerves to recover , that leg itched for almost 9 months straight.
Its defiantly a warning system like bug bites or movement on the skin that is too un-discernable will appear as an itch. I notice scratching as well when bored or full of anxiety.
All Highly speculative . But fun.
Posted by: Revnant Dream at July 10, 2008 3:38 PMHumans are social creatures: in cave-times, when a fellow creature was tired, itchy, or nauseous, we may well have had the same need to sleep, cooties, or bad food to be rid of.
Posted by: Binks, Webelf at July 10, 2008 3:41 PM
some itches should not be scratched.
Posted by: old white guy at July 10, 2008 3:55 PMTest of Theory:
If Dr Fruit Fly shaves off his facial hair without Gore's knowledge.
Does Gore still have that “Itch” in his groin area?
Is that itch cured by the next encounter?
I had an itch at my desk yesterday just as someone was approaching. I smacked the back of my neck and killed a “blood-sucking” mosquito. I was chastised by the gentleman who approached, he said "your not very civilized" and then proceeded to ask me to wash my hands. Apparently some others heard this conversation and one person commented "that guy has some nerve to ask you to wash your hands, he is constantly picking his nose." and we all had a good laugh.
Later that day I found out some people believe that souls can be reincarnated into animals and bugs, so you have no idea whom you are swatting. I have concluded that if the mozzi was someone who has died, it was probably someone’s “money-sucking” X wife.
there was a young lady from Natches........
Posted by: john begley at July 10, 2008 5:05 PMNow that I "know" toddlers who say "yuk" to certain foods are racist,
maybe we should ask the British nanny state nuts if there are some types of itches/scratching that is considered racist?
Good one, John Begley!
Posted by: Malcolm Cross at July 10, 2008 5:33 PMKAte, you have to do a post on this.
Red Tory loves to try to embarass you all the time so I think its your turn.
RT made a post about a drought in Iraq saying this has everything to do with global warming.
I provided him a link which proves that droughts have happened throughout history.
He then went on to say the following.
redtory
July 10, 2008 at 2:55 pm
Bill — JK seems to think that I’m advancing some theory or that I believe this is conclusive evidence of climate change. Far from it. I still remain somewhat skeptical about the whole notion. However, it is one of those things you tuck away for later consideration when summing up the case for/against the proposition that we are possibly in the midst of “global warming.” Kind of like the ice dissipating around the North Pole. JK won’t find that in any history books!
RT just admitted he is a skeptic about global warming. This coming from the biggest mouth piece on liblogs.
Here is the link.
http://redtory.wordpress.com/2008/07/10/tales-of-the-warm/#comments
I really hope you will do a whole post on this because RT has admitted that he is skeptical about global warming and that would fly in the face of his hero Stephane Dion.
John B..hee hee hee...!!
Posted by: kursk at July 10, 2008 6:49 PMThis Itch thing actually dove tails with serious research into the Twin-factor, and the search for communications that may be faster than the speed of light. Last I heard they had a NASA experiment planned which would provide the distance needed for comparison measurements.
Posted by: Phillip G. Shaw at July 11, 2008 3:38 AMOpen wide. What about a great big yawn? you hear it or see it, well you do it. as a matter of fact I'm yawning now
Posted by: kelly at July 12, 2008 2:27 AM