Time delayed pain

[woodpam]

Why, when I stubbed my toe, did I know it was going to hurt (a lot!) before I felt it? It can't be the distance from the toe to the brain as when I cut my toe instead of the nail I felt it instantly. Any idea?

[Think Deep]

I'm no expert here, but could it be adrenaline blocking the pain when you first stubbed your toe?

[Squirrel]

I've heard that there are very few nerve endings in the soles of the feet. If this is where your skin was punctured, maybe there is a chance that the nail entered between sensitive areas. The subsequent pain could have been just general injury-induced soreness, and thinking to yourself 'That's really going to smart' will increase how much it hurts. When you cut your toe, there would have been several sliced nerves (if that's the right term) so you would have felt it instantly. A way to test how sensitive your toes are is to bend a paperclip into a 'U' shape, where the prongs are about half a centimetre apart, and have someone prod your toe with either one or two prongs, but not tell you which. You then have to see how many you got right.

P.S. Drawing pins are the worst - no damn time delay when that happens!

[Kit]

This is to do with the different types of nerve endings in the skin. There are 2 main types of nerves associated with pain: A fibres and C fibres. They are both hit at the same time when you stub your toe, but they conduct impulses at different speeds.
A fibres are thick, because they have fatty insulation, the myelin sheath. This insulation enables them to conduct impulses very fast - 11-35mph. They are responsible for conducting touch and sharp, easily localised pain. The message travels quickly up to your brain and tells you you've stubbed your toe. It's slightly sore at the time, but not very unpleasant.
There is then a delay before the message from the C-fibres reaches the brain. C-fibres are thinner than A-fibres because they don't have a myelin sheath, and conduct impulses much more slowly - 1-4mph. They are responsible for the less easily localised, unpleasant sickening pain that comes after you realise you've stubbed your toe.
It is possible to block the C-fibre messages, at least partially, by stimulating the A-fibres. This "closes" a "gate" in the spinal cord and prevents C-fibre impulses from reaching the brain. Remember that A-fibres conduct touch as well as pain. If we're hurt we rub it better, put it under the cold tap, wave it around in the air etc and this skin stimulation blocks some of the C-fibre messages so the ensuing pain isn't so bad.
Swearing can also be helpful, although I haven't a clue why.

[Squirrel]

Wow, didn't know that Kit. Speaking of pain, have you heard of the surgery patients who are hypnotised before an operation, and apparently can't feel a thing? I wonder what's going on there.

[Kit]

Interesting question, Squirrel - I'm not certain how hypnosis works for pain relief, and I've never used it.
However, there are a few possibilities: firstly, the brain has a tremendous influence on the body - eg you can make your mouth water by thinking about food, and every time I even think about going to the dentist I get sweaty palms and my heart rate goes up. Conversely, there is an increase in the body's natural painkillers, endorphins, when you're feeling good and it's possible that hypnosis builds on this type of response, and positive thoughts/relaxation reduce the release of stress hormones and increase the release of endorphins.
Another explanation is that if we feel that we are in control of a situation, it makes it easier to cope with. The pain is still there, but if it is suggested to the patient that they are in control and that they can deal with it, then it does not bother them as much. Patients who are taught things to do to relieve pain themselves after surgery have lower need for painkillers than those who those who are not taught what to do.
Another means by which hypnosis may help is distraction.
The meaning of pain is also important; studies of wounded soldiers have shown that they may not complain of pain as much as you'd expect, because injury means that they will be removed from a dangerous situation. It is possible that under hypnosis it may be suggested that the pain is unimportant, or that it isn't pain but a different sensation eg heat - I've used this "conversion" strategy quite effectively when I've had pain, although I wasn't hypnotised.

[woodpam]

Thanks for these very impressive answers. Again, I can't make the star rating thingy work but you all deserve them.

[ANUSHIKA]

I'm noy sure but what I do no is that about 10 min after reading this i got up and stubbed my toe, and all I could think about was your question on answerbank, and yes it did hurt :)