Why does sunburned skin feel hot to someone else?

My wife and I painted a wall outside yesterday and managed to fricassee ourselves pretty good. Not to the point of blistering, but let’s just say I’m a walking etymology for the term “redneck.” When I woke up this morning, I noticed that the burned areas of her skin feel hot to the touch.

After 18 odd hours, I have to believe the actual heat absorbed from the sun has dissipated. So what causes the burned area to be hot to the touch? Does the skin’s healing process give off heat?

I tried google, and found lots of sites that list this is a symptom, but none with an explanation.

I thought maybe it’s just an illusion, despite all the medical sites that note it. So I tried to do a blind test, and closed my eyes while I had my wife move my hand to burned and unburned patches of her skin. Results were inconclusive: I couldn’t really feel the difference after all. But this was a couple of hours later, and I wasn’t really fooled by the “blind”: I know which parts were burned, and I found it easy to guess where I was touching.

So anyone know if this can been measured objectively? And if so, what causes it?

In brief, tissue near the surface of the body is damaged, here by sunburn. Blood vessels in this region dilate, the better to carry cells and blood products which fight infection and repair damage. The vascular bed in this region becomes leaky, allowing the aforementioned substances to leave the bloodstream and enter the tissue bed. Net result: increased perfusion of the damaged area, bringing warmer, core-temperature blood and other substances to an area that’s generlly otherwise cooler than the rest of the body.

I’ve got a painful hangnail happening on my left thumb, and have noticed it’s significantly warmer than the surrounding area – same deal?

[irony]No, hangnails are fundamentally different. Here it involves nuclear fusion properties. The hydrogen atoms slam against each other, and fuse into Helium atoms, with the loss of mass and corresponding release of energy. While this is healing, please notify your local Nuclear Regulatory Commission.[/irony]

Yes, it’s the same deal.

Okay, not the smartest question I’ve ever asked, I’ll admit it. :rolleyes:

Twickster, what IS the smartest question you’ve ever asked?

Sorry, I should have included a smilie. :smiley:

You gotta admit, that’d be pretty cool. We could get power cheaply and cleanly just by putting the unemployed to work as power generators by giving them all hangnails and hooking them into the grid somehow.
Hey, they used the same principle in The Matrix.

Oh god, I don’t know, probably some esoteric hypothetical scenario in sociological theory when I was a grad student. I peaked a long time ago. :wink:

Really? Cool! I’m going to have to patent this and…

Oh…my browser didn’t parse the [irony] tags…shoot…and I thought I was going to announce slightly-more-that-room-temperature fusion to the world.

Stranger

:dubious: Wouldn’t this be sarcasm, not irony?

:smiley:

I’ve always felt that if we could somehow harness the energy of human flatulence, we could tell the Saudi’s to kiss our ass.

  1. Harness Fart Power
  2. ???
    3.Profit

Only if you cure it in a hyperbolic chamber first.

Geee, I do that too sometimes…



but not when we’re both sunburned :slight_smile: