Pain tolerance and distribution of pain thresholds

[Ladewig]

The other pain thread reminded me that I had been meaning to ask these questions.

Are pain thresholds normally distributed?

How does one tell where one falls on the distribution. I used to think I was slightly above average, then that I was slightly below average, and now I wonder if I am even lower?

[TruthSeeker]

The easy answer to this is "yes and get tested"

The more complex answer is:

Pain threshold, the lowest level of stimulation which is reported as painful, is normally distributed in the population. There are variations, however, based on the type of stimulus (e.g. thermal, punctate, pressure, electric) and the site of the body (there is some controversy about this). Further, there are variations between the genders with some evidence that threshold changes across the menstrual cycle in women (again, the pattern of these changes may be modality specific) and variations across the life span (again, possibly modality specific)

How to know where you stand? Well, you'd have to be tested and compare your data with that reported in studies usuing samples comparable to you.

The difficulty with testing threshold is that you have to control body site, demand and response biases, attention, meaning of the situation, anxiety, instructions, even experimenters. For instance, there are data that men perform differently for male versus female researchers :)

Not as simple as it seems at first, is it?

[Hydrogen Cyanide]

Also, to complicate matters there is the problem with individual nerve function.

Some people (and I am one of them) seem to have high thresholds for pain... but actually have poor nerve receptors, and very poor responses to stimuli. I have had a doctor warn me that the procedure she was going to do would cause some pain, and then praise me for being very stoic --- when I had NOT felt anything. I also get cuts and bruises without feeling them.

Fortunately, it is not a TOTAL lack of pain awareness. I will feel certain things (broken bones, sprains, and stupid cramps). I have damaged nerve endings on the front of my calves (I fell on a hill while trying drag a reluctant toddler from a wading pool while very pregnant with child #2). Sometimes these nerves fire off for no apparent reason. Sometimes it is pain, and for a while it felt like warm water was running down my leg (really weird with two tiny boys in the house!). Fortunately the phantom pains have dissipated, now only to occur when I put pressure on that part of the leg.

I had an interesting conversation with an anesthesiologist (sp?) at a Brain Week Open House ( http://faculty.washington.edu/chudler/baw.html ) that there have been cases of people with low pain awareness who were not aware of serious bodily damage like an appendix rupture.

That professor who put on that Brain Awareness Week has a pretty good page on pain: http://faculty.washington.edu/chudler/pain.html

[Art Vandelay]

I can't think of many situations in which it would be worthwhile to investigate one's pain tolerance. Seems a bit like investigating one's tear gas tolerance to me; rather masochistic, isn't it?

I don't see how pain threshold can be well defined. There's everything TruthSeeker mentioned, plus quite a bit more, such as the fact that it is subjective as to what is pain and what is just stimulation.