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I have a PhD in neuroscience, where I studied circadian rhythm disruption and its effect on pain behavior. So I feel qualified to discuss this.
In humans, pain has two primary components [0]:
1. The sensory-discriminative component: where on my body, what type (hot? cold? chemical?), and how intense is the noxious stimulus?
2. The affective-emotional component: how much does the pain hurt, and how does it affect emotional state?
Very importantly, both #1 and #2 are considered “pain”, and they can be experienced both simultaneously and independently. Pain is entirely subjective, as TFA highlights.
It does sound valuable to search for biomarkers of the sensory-discriminative component. But I’m doubtful that biomarkers for #2 are readily observable, beyond fMRI. The “Nociometer” may capture this, but what if it doesn’t in a reliable way, since it’s designed to test #1? TFA discussed how this could save money for health-care system money; this gives me an awful feeling.
Relying on “biomarker-based pain measurements” worries me that patients who are primarily experiencing affective-emotional components of pain will only further be doubted or not trusted by physicians.
There are already far, far too many examples of physicians not trust patients about pain. Re: women at Yale undergoing IVF treatments without fentanyl injections due to a drug misusing nurse stealing the fentanyl. Physicians responded to the unanesthetized women in excruciating pain by saying, “maybe you are immune to fentanyl!” [1*].
I think we should tread lightly.
—
[0] https://pmc.ncbi.nlm.nih.gov/articles/PMC6676053/
[1] https://www.nytimes.com/2024/09/09/health/yale-ivf-egg-retri...
*There is a heart breaking podcast on this scandal, which is how I originally learned about it [2]. Of course when I was in horror telling my wife about the story, the news came as no surprise to her, as she’s experienced pain disbelief from physicians her entire life.
I remember that after I had surgery on my finger (the bone healed wrong so they had to cut it and rotate it), a nurse asked me to rate my pain 1-10, and I said: "it's alright, like a 7?", and she was like "that's not alright, let me give you some meds".
It did actually feel like a 7/10, it really hurt, but somehow it didn't bother me. And it was like that for weeks after the surgery, I didn't really end up taking any pain meds when I got home.
And I wouldn't say my pain tolerance is generally particularly high, pain does usually bother me as much as anyone. Not sure what that was about.
I never understand those charts. To me a 10 is a state that only briefly exist before I passed out from agony. If I was at a 7 pain scale you wouldn't need to ask me, it would be obvious.
I think mental disposition is a huge component of perceiving pain, and it can be entirely sub-conscious. I can't speak for your case of course, but perhaps you were "ready" for the pain in your finger and what is to come and thus the panic inducing element was gone. You could be almost just an observer of the pain rather than the subject.
Fear of the pain can make things much-much worse. If that fear is removed, you won half the battle.
Of course, there are levels of pain where all of the above goes out the window and it is absolutely debilitating, but maybe that's the 13/10 pain level that hopefully most of us never have to experience.
Coming out of a surgery once, the nurse asked me if I was in pain.
I said “No, I don’t think so. I feel like crying, though.”
“Well, that’s probably because you’re in pain.” At that point what I considered as pain hadn’t really manifest yet.
That sounds a bit like pain asymbolia. I'm surprised it would happen in just one instance, but I don't know much about it.
Where on the finger? From personal experience, the finger tips can be excruciating. Anybody that’s gotten stitches knows that nothing compares to the initial administration of localized anesthesia.
If a level ten is passing out, that one would win via Price Is Right rules.
> There are already far, far too many examples of physicians not trust patients about pain.
I am friends with a couple of ER doctors, who are probably the worst offenders (self-acknowledged) in this space. It's based on a real phenomenon, though, of drug-seeking behavior.
As people with chronic pain communicate with each other (through things like Reddit) on the best way to communicate to doctors that their pain is legitimate, those techniques are also inadvertently taught to other people who are seeking pain medication for recreational purposes.
I think the cause of widespread drug legalization has been weakened by a couple of real world efforts in that direction, but I still stubbornly cling to the belief that if people are allowed to make their own choices, then you can partition the recreational users from the chronic pain sufferers and maybe let medical science have a slightly better change of addressing the latter case. That said, given factors like cost and insurance coverage, it may just be a realigning of incentives rather than fixing the problem itself.
> but I still stubbornly cling to the belief that if people are allowed to make their own choices, then you can partition the recreational users from the chronic pain sufferers
I can empathize with this thought (having had an episode of pain disbelief in a hospital myself) but the idea of partitioning recreational users from chronic pain sufferers isn’t reflective of the reality.
They aren’t two mutually exclusive groups. In fact, many recreational users get their start from over-prescribed opioids. Some people experiencing pain and all of the associated emotional difficulties will see the sudden access to opioids as an opportunity or even an excuse to indulge in opioid excess.
Self-medication with opioids also produces a very quick on-ramp to dependence in average users. If you’re anything like me, you prefer to use the minimum dose of any medication and get off as quickly as possible. I’d rather have mild lingering headache pain than take an extra Ibuprofen.
Not so with the much of the general public. I have friends in medicine who believe even Tylenol should be prescription only because of how frequently they see people destroying their livers by taking excessive amounts. Look at simple drugs like Afrin nasal spray and people who become severely dependent for months or years because they can’t even read the directions on the bottle. Open this same door to something euphorically reinforcing like opioids and the number of people walking themselves straight into addictions because they wanted something stronger for the occasional headache would be massive.
>> you can partition the recreational users from the chronic pain sufferers
Except that you can't. There is no bright line between those two groups. Many recreational users/abusers started their journey when prescribed drugs for legitimate pain. Steady use becomes dependency, then you look for other sources, and quickly you are crawling dark web for a dealer in your neighborhood.
I'm fascinated by the athletic side of all of this.
I have a friend who has had the aspiration to become a regular exerciser for years, but he says everything he tries just hurts too much. I exercise regularly myself, but we haven't found a way to talk about it, because it's so hard to share subjective sensations of pain. In some sense, everything I do hurts, too, and everyone who works out or plays a sport acknowledges a lot of pain. People differentiate routine pain from pain that requires effort to endure and distinguishes both of those from pain that indicates an injury happening or being aggravated, and people value and hone their ability to distinguish the second two from each other, because they don't want to get injured but also don't want to let pain hold them back from doing something that makes their body healthier and stronger.
I've known people who have endured through pain and suffered terrible consequences from it. Five years ago, my wife's aunt loved to say "I'm a tough old bird," and she has since lost a leg unnecessarily, because she thought that having high pain tolerance was a viable alternative to going to a doctor. Now she's in a wheelchair and does everything the doctors say.
Other people have had opposite experiences, where learning to disregard pain led to breakthroughs for them. One woman I know set a big triathlon PR a year after having a kid, and when people asked her how she was able to do that, she said, "After having a kid, the pain just wasn't a big deal to me anymore." She's big into the science, so I expected to hear something about hormones, but for her, her expanded pain tolerance was the entire explanation for her better performance.
Personally, just doing normal exercise presents me with an incredibly rich variety of "painful" sensations and a lot of difficult decisions. Right now I have a nagging shoulder injury, and every time an exercise generates a "painful" sensation in my shoulder, I have to decide, is this reflective of something making this injury worse? better? neutral impact? Should I stop right away so I don't aggravate the injury, or should I do this exercise more often because it's stimulating the tissue in just the right way? There's so much said and written about it, but it often seems frustratingly tautological. You have to know what the sensations mean before you can figure out which words refer to which sensations.
It's complicated. Do any kind of sports and muscle pain will just mean you worked hard, which is generally good.
Do a martial art and you'll learn to ignore pain from hits to non sensitive areas too.
But if you have a brain you'll still care about joint pain and pain from hits to areas where it could cause serious damage.
I'd let that shoulder heal a bit :)
Personally I've always figured I should pay attention to the derivative of pain over longer periods when doing sports.
Yeah DOMS sucks, but the average derivative over time is zero. It doesn't get worse with more sport. If your shoulder is the same it's probably fine to keep sporting, if it gets worse over time you should definitely give it rest and probably get it looked at.
Not surprised either, I've met a doctor who trusted me that I was in pain exactly once, every other doctor or nurse has looked at me like I was some kind of drug addict.
The strongest such look I've ever gotten was a nurse in the ER when I went in with a splinter under my nail. I already felt kinda silly to go to the ER for something so obviously harmless, but it was late I just couldn't handle the pain. She'd offered me ibuprofen, but I had already taken the largest recommend dose of that, so I asked if maybe I could be given a local anaesthetic. She looked like she was considering whether to call the cops, since I was obviously a... Well what, actually? Local anaesthetic addict?Is that even a thing? Why would that be a thing?
I've come to the conclusion that healthcare in my country is better at judging you than they are at caring for you, which is really fucked up
I'm not sure how this fits in, but in my experience a further complication as someone with chronic pain/illness is that often the thing that bothers me the most isn't what I would describe as painful. I would describe it as very uncomfortable but on a different axis than pain. As a simple example that I think most people can relate to - I do not think of being dizzy as painful, but it's very impactful if you are dizzy all of the time. I had an episode of vertigo that was one of the most miserable experiences of my life but I don't think I experienced much pain during it.
I guess if the goal is to tell whether the person needs pain meds that complication may not matter as much since they don't help (afaik) with those symptoms. But I do sometimes feel like my health problems get taken less seriously if I report on my pain levels rather than my discomfort and/or how it impacts me. Eventually I found a migraine pain scale that focuses on how it affects your life rather than directly how physically painful it is and that helped me have a normalized system for reporting.
Even neuroimaging isn't enough. fMRI doesn't have a great track record for predicting pain. It works to an extent, but it's not like there's a simple area that lets you accurately and directly decode the pain level someone is experiencing. And there's no new neuroimaging in the pipeline that would let us do this in a clinically relevant setting. There's a lot of hype around various optical methods, but it'll be a long road even if they work.
In the meantime, we should take much more advantage of the gap between the sensory and the affective components!
There are many other science-based pain management methods than just drugs. These other methods don't change the sensory part, the pain is there, but they can dramatically change the quality of your life with how you feel the pain.
CBT is very effective for pain management. Even something as simple as distracting yourself from a painful stimulus like a medical procedure can make a huge difference.
For example, your doctor doesn't routinely tell you to show your kids a fun video while they get a shot. But it makes a massive quality of life difference. Without Elmo, my daughter will cry for 5-10 minutes and just be miserable for half an hour. With Elmo, the shot comes, she's annoyed, there are tears for a 5-10 seconds, and then she's fine. There's no reason to not make this routine, except that we think of pain as something entirely objective instead of something that is largely subjective.
I think this research falls into that trap of "This is an important problem, this solution is obviously bad, but we have no good ones, so let's do it." This is likely to cause far more pain than to help anyone.
There are other MR techniques that show promise. The below links are for disc pain assessment. As a tech at a high volume spine site, the DeVa technique is fairly appealing, as spectro is slow.
2. The affective-emotional component: how much does the pain hurt, and how does it affect emotional state?
I am going to add the spiritual aspect to this. I read a post on Reddit asking if Jesus truly suffered more than anyone else on earth, given that more people suffer for longer than his 24 hours ish on the cross.
Without believing the story of Christ at all, I was still able to do the mental exercise to see that the nature of the pain had nothing to do with the duration. For example, watching your mother watch you get crucified is heart stopping (or to watch another mother have to go through that).
So, what is the purpose of a human feeling that pain as an experiencer or as an observer? Why would our body elicit that psychic pain, why wouldn’t we just focus on the physical and ignore these other things? In that moment, your only concern should be the physical, but it’s not just physical.
The psychic pain almost has no use in a state of physical torture other than to inform the conscious of its duty to morality. Unfortunately, I do not believe science can ever conclude this is the answer (in no possible way, I’m open to being wrong).
Like it's a pretty interesting research question to see if this very major component of the human experience can be seen and measured, but I'm not entirely sure what the medical value of such a thing could be if what you get is basically just yes no in pain or not and a rough intensity because you can already get that and more from the patient.
My experience was/is annoyingly the opposite where I developed chronic neck pain on a relatively fast timeframe and I can't find a physician across all different disciplines that's actually interested in finding out the source. They almost immediately throw up their hands and want to send me to a pain management doctor.
I've found meditation very useful in this regard. If you focus on observing in detail #1 type pain, you find that the #2 becomes much more managable. The technique is to get curious about the pain, ask what type it is (hot/cold/electric etc), where exactly is the pain. what shape is it? how does it change over time? It sounds counter-intuitive but by focusing on it it becomes easier to manage (because I think a lot of #2 is story and mental reactions to the pain rather than the actual pain itself and the mental reactions are self-fulfilling in a negative way).
Maybe this explanation is intentionally simplified, but what it’s telling me is that medical science is just lost.
Is it possible to have just 2 without 1? Do clinically depressed folks fall under this category of "the affective-emotional component without the sensory-discriminatory component"?
why do you think psychological types of pain won't cause discernible biomarkers? well known, for example, that stress has lots of effects on the immune system
it's all part of the same biological soup!
I've been interested in pain and pain management since having a drunk driver crash into us. I've even moderated a panel of doctors who specialized in pain.
How people deal with acute vs chronic pain can be very different. One doctor blew my mind when he described chronic pain as a spousal relationship. It's something you have to live with and work with. You can't ignore or bully pain.
Also men and women deal with pain differently. Most men describe a heart attack as the worst pain ever. Many women have ignored heart attacks because it wasn't as bad as their period pains. Women also describe kidney stones as worse than childbirth.
I had a friend go in to the doctor and described the pain as a 5. But the doctor noticed they were sweating because of pain, which made it at least a 7 in their experience as that was an involuntary physical response.
I've been to places not described on the pain scale, when I was recovering from surgery the IV drop ran out, the pain was so bad my spirit phased out of my body slightly so I was less aware of the pain but could still see the nurse running around trying to load another bag into the IV dispenser.
I can tell when a bad storm is coming because it feels like water running down the inside of my leg bone, like runoff down a gutter. Some days the pain is dull and I can get irritated easily, but some over the counter pain medications are helpful. So if I am going to the doctor I've already exhausted the available options, so pain is high priority to me as I can't do things.
I have also noticed that men's pain is taken more seriously than women's pain. Redheads get less pain relief and if you are person of color, especially a female, doctors take your pain least seriously. It makes me wonder how they actually teach in med school for that to happen.
Describing the pain in terms of what work I can and cannot do gets more attention than anything else.
It is crazy to me that womens’ pain is so ignored. I’ve always (half-) joked that if men got periods, there would be 30 alternatives to midol by the end of the month. Maybe we’re just better at crying like babies?
As a chronic pain sufferer, I experienced the same as you, explaining where I am limited in life rather than expressing how much pain I’m in gets much better results.
A similar problem I’ve had is that I tell my doctors I have terrible sinus pain. Often the response to that is that I should consider allergy meds, as well as a confirmation that I am indeed “pretty stuffed up”.
But when I say I cannot sleep a full 8 hours due to sinus blockage, suddenly we need sleep evaluations, humidifiers, antihistamines prescribed, methods for lubricating my sinuses, netti pots, etc.
Chronic “pain” as a spouse is the perfect metaphor. I can’t push through it, I have to use patience and understanding and it’s always somewhere on my mind. That’s the only way to make progress or be sane long term. I’ve grown and matured because of it. I’ve also experienced the post surgery pain that briefly takes you out of this world. For a split second I was in the Hell dimension a la Event Horizon the movie before I had taken my first dose of opiates and had adjusted my arm too much. I don’t mean the pain was hellishly bad; I didn’t cry out which is probably what a 10/10 pain would elicit. It was more like dread and “seeing” but not with vision the mutilated flesh and gore inside my repaired wrist.
"Redheads get less pain relief" - are there any references you have so I can explore this more?
In the meantime if you are actually in chronic pain it's worth knowing research has shown that 6 out of 10 is the best number for patients to use. Below 6 and insurance doesn't pay out and healthcare workers consider it normal and if your not writhing and scream on agony right now you can't possibly be above. 6 has the best chance of success.
Alas even the best is not a high chance there are millions suffering chronic pain, because in the absence of a biomarker and withdrawal of opioids, many probably most sufferers are left without any relief and suffer the consequences. It's not about you it's about the doctor there was nothing you could have done, prejudice and stigma over pain is rife within healthcare.
Probably not exactly the same but I remember trying to describe a type of pain I felt to a doctor in the US. I called it "sour" (which is how it would be described in Chinese) and the doctor laughed saying that didn't mean anything to him. I think it is extremely accurate and descriptive but to him it didn't even register as having meaning.
I am often baffled by how some people are able to articulate how a specific pain feels or even where exactly the pain is. Describing pain intensity is hard beyond "not very painful" and "very painful". But adding a dimension of pain type is something I struggle with. Sour pain makes as much sense to me as piercing pain, which is to say: no sense at all.
I've been pierced (not for fun or aesthetics) by large nails in an accident, and it felt nothing like the icepick headaches I get, which my doctor tells me are a piercing pain.
Human internal experience is weird as fuck. If it can help diagnostics in any way, I'm all for more precise pain measurements. But I'm sure someone will abuse that research for torture.
I think the closest proximity to suan/sour is just sore. I like the suan metaphore, like something marinated/fermnated/drowning/gone slightly off in dull pain. It wierd because "sour" does feel very apt descriptor, English has sharp/stabbing/throbbing/burning/shooting/stinging/tingling/numbing... etc lots of metaphores. But "sour" is just your default sore/ache.
There are clearly different types of pain. I use the french words for high and low pitch to describe two groups of pain, although I never used them.with a doctor because it would be meaningless for ut
Any kind of accurate pain measurement mechanism would be revolutionary in veterinary care.
We recently found ourselves in a horrible situation. Our dog rapidly came down with a mystery illness that saw him go from bouncy to unable to stand in the span of a few hours. 6 hours of testing, 2nd opinions and specialists on the other side of the planet, and noone had a clue what was going on. A ridiculously primitive pain assessment was run, and we were advised that the dog was suffering and we should let him go.
Millions of animals are put down every year on the premise they are in pain, usually without strong data, with owners left to wonder if it was too early.
I added a children's pain scale to some software (faces in varying levels of pain that children can point to). I know my mom had chronic back pain that she complained about, but I never really thought about it. She functioned, she got through life. She was over for dinner at the time and I must have brought the scale up in discussion. I grabbed a paper copy and asked her what her pain level was, and she pointed to the second worst. Even after that I just kind of wrote off her pain like, she functions (though sometimes I would have to go get her as she got stranded in a supermarket in too much pain to move), and that's just life. I can watch a movie of some random acting dog whimper and fake limp and have to wipe tears from my eyes, but almost instantly went to ignoring my own mother's pain because she powered through. I hope it's not because acknowledging my mother's pain would have created a cost for me (doing more for her, acknowledging would create a long term burden on me versus the quick/easy/kind of cathartic/self serving release of emotion of a sad movie) but part of me thinks that's partially the case. What's the point in measuring when our response is still just a shrug?
I've been recently wondering if this is a "thing" in medical research, and I'm extremely glad to hear that it is. Especially in tech I think we all know how frustrating it is to only ever get vague, pre-interpreted reports of issues, particularly when those issues are non-deterministic or otherwise tough-to-reproduce.
I can only hope that once these methods mature to everyday use levels, people will keep in mind the gap between the measurement and the phenomenon. Just like how a GPS tracker doesn't track the object (or pet, or whatever) you put it on but itself, these methods will also only detect pain they're compatible with detecting, and miss others. I can already imagine the conversations with various parties insisting that a patient isn't actually feeling pain because whatever devices are not reporting so (or the opposite!). Still, I don't think this should keep these devices from existing.
They might miss a type of pain that the current trials aren't measuring because healthcare doesn't believe that group of patients and further entrench that prejudice into the measure. It's a very real risk of such a device.
Hard challenge, as pain is a subjective definition and you can't intellectually comprehend it until you're in it.
I got the scale 10 questions before I had a badly herniated disc and never knew what to say.
Now I can tell you that a 10 is when you're begging for mercy. Hearing yourself whimpering. Having panic from making another move, another step.
To be clear, it is not just the amount of pain itself - it's also a function of duration and consistency. Once pain always fires, in any position, and no remedy (besides a Fentanyl infusion) provides even temporary pause, you get in a spiral that kills quite a lot of people.
Sometimes called Chronic Pain, it is easily dismissed but so damn hard to comprehend until you experience it. Like Tinnitus, just with the rawest brain signal that triggers fight or flight.
Coming back to measuring pain - that time axis is critical.
Another one with an, “I dunno, 5 maybe?” story. I had a heart attack 2 months ago and got asked the 1-10 thing 4-5 times in the middle of it. I had classic left side chest and back of my arm pain. Kinda made up a number but told them I definitely felt shitty.
I did ask my cardiologist how she’d rate my heart attack on a scale of 1-10 for severity. She laughed and said nobody had asked her that before. Then said 7.
Pain is relative to experience and tolerance. Using patient input is inherently flawed.
I'm unsure how to interpret this statement. Are you saying that the amount of pain experienced depends on the patient's prior exposure and some 'tolerance' stat? And that we should ignore their actual statements about, and reactions to, stimulus when assessing the effect of that stimulus on them?
a graduated set of instuments
starting with a short, thin, very pointy pin
then the same, dipped in weak.acid
then bigger pins, and stronger acids
the get them hot
etc,etc
sort of a micro tortures starter kit, but all calibrated
and then a big pile of money, to attract volunteirs
there is already a group that has been doing this with insect stings and bites, with the worst bieng
some kind of mega sized japanese hornet, which the
description of was, as an awe inspiring combination of bieng stabed with something dipped in hot acid, so.....
Pain is relative because the psychological factor can amplify pain, say, someone afraid of getting a needle. The amount of hate they have for it definitely makes it worse
I think it's great to bring more measures of pain to bear on things but admit I'm disturbed by the rhetoric around things. It's a classic problem with measuring anything neuropsychological: pain is inherently subjective. So when I read an entire article talking about how we need "objective" rather than "subjective" measures of pain it seems not only logically and scientifically misguided, but also inherently dismissive of patient experience, like their subjective experience is irrelevant. The thing you're measuring is a subjective experiential quantity.
There's so much literature showing that inherently "psychological" things are integral to pain experience there's no way to disentangle them. Another poster was noting that pain is affected by experience — so if a pain is new to a patient, does that mean we should ignore their experience of it? If we know that pain perception is amplified by anxiety or fear, we should dismiss it?
I know from firsthand clinical experience the problems with report of pain — misrepresentation in drug seeking, for example — but I almost feel like you'd be better off studying that than anything else. The rest of the stuff they mention is great and all parts of the puzzle but it's all minor parts of the whole process of pain perception, and the whole idea of dismissing "subjective" pain seems absurd to me, because pain is subjective.
True scifi will be when the doctor can use a machine to feel what the patient feels.
"Ah, now I see Mr. K. Dilkington. You clearly have old cold belly badness."
This is a Black Mirror episode based on a short story by Penn Jillette (of Penn & Teller)
Poor misunderstood Karl. I knew what he meant when he said that glass ashtrays hold cold.
I have never had a doctor ask me what flavor my pain is, but I can easily describe various types of pain as e.g. spicy, sour, bitter, etc.