Listener supported. WNYC Studios. This is Science Friday. I'm Flora Lixman. Today on the podcast, understanding the complex relationship between mental health and chronic pain. I think for some people, the message, it's all in your head, suggests that you're making it up. Chances are you either have some type of chronic pain or you know somebody who does. It's remarkably common. Roughly 20% of adults in the U.S. live with it.
And people with chronic pain are more likely to have depression, anxiety, and substance abuse disorder. But this relationship between physical and mental health is not as straightforward as you might think. And the latest research suggests that untangling the connections between mind and body is a key part of developing better treatments for people who have chronic pain.
Joining me now is Science Friday producer Shoshana Buxbaum, who has been reporting on this topic. Hi, Shoshana. Hey, Flora. So let's back up for a minute and just like go through the basics. What exactly is chronic pain? You know, how is it defined? Yeah, so chronic pain is just any pain that lasts longer than three months. It's sort of a big umbrella term. It covers a wide variety of conditions.
It's kind of easy to think about chronic pain based on where it happens in the body. So like a migraine versus lower back pain. But chronic pain researchers have recently started to classify chronic pain conditions by actually what's causing them. Is the pain the result of an injury either to tissue or nerve damage? And then there's this last type, which is not quite as well understood.
And it's pain that's due to changes in the mind and in the brain. And these changes actually disrupt how your body processes the pain. And of course, to make it extra complicated, sometimes chronic pain is caused by a combination of both like physical and mental or psychological. What made you want to look into this, this relationship between chronic pain and mental health? Okay, so it's a bit of like a me-search project, as we like to call it.
But yeah, so I was diagnosed with a chronic pain condition now like a decade ago, maybe a little more. And as patients that have these type of conditions, like I went from doctor to doctor. And no one could find a specific physical cause. I didn't have an injury that was causing my symptoms. And so along the way, I was met with a bunch of different versions of it's all in your head. And I felt kind of like I was handed a modern day hysteria diagnosis.
Good news, I did eventually find my way to a specialist. who explained this mind-body connection in a way that finally clicked for me. And a combination of treatments finally began to ease my symptoms. But of course, being a journalist, I wanted to get to the science behind what was going on. My nerd brain was like, I got to go deeper. And I really wanted to understand how mental health interacts with chronic pain and if having anxiety or depression can actually lead to developing chronic pain.
So I called up Dr. Lauren Heathcote, a health psychology researcher at King's College London, who studies how psychological experiences impact our bodily sensations. We have some good evidence. that there's a bi-directional relationship. So both directions are true. In some cases, understandably, someone develops a chronic pain condition and the stress...
of living with that condition can lead to the development of things like anxiety and depression. Interestingly, that's quite a sort of an ableist. few you know living with chronic pain must cause depression and it doesn't always as many people living very well and without mental health problems have chronic pain but we also have some evidence the other way around that either having a predisposing mental health problem seems to then predict the onset of later chronic pain.
And there's also evidence that actually there's a shared underlying vulnerability that makes someone vulnerable for developing both chronic pain and mental health problems at some point in their life. And there's still a long way to go to fully understanding these underlying mechanisms, but scientists are starting to put the pieces together. Dr. Yoni Ashar is one of them. He's a clinical psychologist and a neuroscientist at the University of Colorado.
He studies how changes in the mind and brain lead to the development of chronic pain. Some of the most noticeable changes are engagement of brain systems related to Emotion and learning and memory. The way pain is processed in the brain is quite complex. There's no one region that's like the pain region. Pain is processed sort of like everywhere and nowhere. And we see changes along all parts of the pain processing pathways.
But the sensation of pain, whether it lasts for a few minutes or a few years, can feel remarkably similar. I asked Lauren Heathcote, the King's College London researcher. to explain the difference between how the brain processes acute versus chronic pain. I think a helpful but quite rough way of thinking about this is that in the case of acute pain...
we tend to think that the brain is somewhat getting it right. So there's some kind of tissue damage or danger signal essentially coming from the body. and the brain is detecting that signal and producing a pain output. In the case of chronic pain, it's more the case that the brain is getting it a bit wrong. So it might be that there was some sort of initial injury, but that that has now healed, or potentially that...
There is still some ongoing inflammation in the body, some kind of bodily damage in some way, but the brain is still producing a pain signal, even when it's not particularly helpful anymore. And it's a tiny bit more complex than... Acute pain is the brain getting it right, and chronic pain is the brain getting it wrong. All pain is mediated through the brain.
Let's say you burn your finger on the stove. Your brain receives that pain input, and your brain is making its best guess on how serious the burn might be. This is a protective mechanism, obviously. The more intense the pain, the faster you move your hand away from the flame and run it under cold water. It's a complex algorithm likely that's going on in the brain and in the rest of the body.
And that algorithm is probably different for every single human. And it's probably different depending on the context that that person's in. So going to doctors trying to seek care, I heard a lot of variations of, well, you know, it's sort of all in your head. felt really dismissive at best and then harmful at worst. I wonder, could we sort of flip this assertion on its head, given what we know about how pain works in the brain, that it's actually important to understand?
the sort of psychological or mental health components of chronic pain. I think you're exactly right. That message, you know, it's all in your head, really carries a huge amount of stigma. And I think is one of the reasons why chronic pain is so under addressed and so undertreated in our society. And it's a difficult message because... I think for some people the message, you know, it's all in your head suggests that you're making it up.
And that would not follow the science at all. But what science certainly has told us is that the brain and the central nervous system, so that's also the spinal cord. It plays a role in our pain experience. And I think ultimately that is a good news story because it opens opportunities. for new avenues for treatments and interventions. One of those new treatments is called pain reprocessing therapy.
It's designed specifically for people who have pain that's primarily due to changes in the mind and brain. The goal is to have patients unlearn the pain pathways that their brain has formed. which are in turn causing them to experience pain. So step one is educating patients on the science of chronic pain and what's actually going on in their bodies.
It's like, say, a car alarm that's gotten so sensitive. Every time a leaf falls in it, the alarm's going off, even though the leaf's actually not dangerous to the car. That's Dr. Yoni Ishar again, one of the lead researchers studying this treatment. And what we always emphasize to people is that a false alarm is just as loud and obnoxious as a true alarm.
So the pain is real. No one's making it up. No one's exaggerating it. And yes, it's truly miserable. But the causes may be quite different than what we thought. So a lot of people come to us thinking that they're bulging disc or they're... arthritis or etc that's the cause of their pain and a major step is education that actually bulging discs and arthritis are highly prevalent in people who have no pain whatsoever and they're typically
not related to the pain. And that's what we think is happening for you. And that education to help people shift their thinking to this pain is actually not a sign of tissue injury. This pain is an indication that my pain system has gotten sensitized.
If you think your back pain is due to a bulging disc, it might feel like a giant leap to even consider a psychological treatment. When we started this work, I was concerned that people would... storm out of our offices and feel dismissed and invalidated. more often it's the opposite of people telling us, wow, now things make sense. Like I saw 10 different doctors before this who had 10 different stories.
And none of it really made sense or could explain all my symptoms. And now for the first time, things are falling into place. Things are clicking. After the break, how effective is psychological therapy for chronic pain? We had results that honestly when I saw them, my jaw dropped. Support for Science Friday comes from the Alfred P. Sloan Foundation, working to enhance public understanding of science, technology, and economics in the modern world.
The first study testing the efficacy of pain reprocessing therapy was in patients with chronic back pain. And back pain is among the most common chronic pain conditions in the U.S. Severe chronic back pain affects over 8% of adults in the U.S., and lower back pain specifically is the most frequent cause of job-related disability in the country.
I wanted to understand what going through this type of therapy was actually like. So I talked to Sal, who is a participant in that first study. We're just using Sal's first name to respect their privacy. So I started off by asking them about when their pain first started. I mean, I first noticed my back pain beginning in high school around when I was 15. I'm in my 30s now.
So, you know, it's been probably more than half my life at this point. It was a daily thing. It's something I woke up with every day. And I think I just. kind of almost resigned myself of like, this is just how my body feels, right? Okay, so can you walk me through your experience with pain reprocessing therapy? Walk me through what the sessions were like with your therapist. So I met with John, he does pain reprocessing therapy, and he himself had
also benefited from the treatment greatly. We met for an hour, once a week for like six or eight weeks. Part of the treatment itself is like acknowledging from like the cognitive. standpoint of like reminding yourself that you're safe and that your body doesn't need to be feeling like fight or flight, right? Learning about the research and learning about
how pain works in the brain and the body is part of the treatment. Right. And I told John kind of throughout the whole process, I said, this is really dumb. And he's like, I know because it, it almost feels like. You know, like there was nothing intensive. There was nothing that I radically learned.
that was different. So it would just be like breathing exercises and focusing specifically, you know, in this spot in my right shoulder that feels uncomfortable or feels pain. And what is the quality of the pain? Does it feel tingly? sharp? Does it feel cold? Does it feel hot? So noticing on the actual sensation of pain and trying to like spread that out or like dissolve it a little bit or just like focusing on it.
And like taking a deep breath while focusing on it. And so just taking a moment to remind yourself and your body that you're safe and that you don't have to carry that tension or that pain. And just even the... small act of doing that provides relief. I would say I went from a daily, like waking up six or a seven pain and just like
just chronic all day, you know, and increasing or decreasing depending on my stress, but I'm at a zero or one. Right. And even now I'm skeptical. I'm like, Oh really? Like I don't wake up with pain anymore. Like that's cool. And I wanted to know if Sal's experience with pain reprocessing therapy compared with the data that Dr. Ashar collected from the study.
We had results that, honestly, when I saw them, my jaw dropped. I was amazed. This was a randomized controlled trial of 150 people with chronic back pain, and two-thirds were pain-free or nearly so at post-treatment. And that's a pain reduction that we rarely see with other treatments. So it's very encouraging. Yeah. And when you started, did you think that you were going to see...
No, when we started, I was quite skeptical of this whole thing. You know, I kind of thought that psychological approaches could help a bit with the pain, like maybe take the edge off. be a little more comfortable. But I did not believe that we'd see what we're seeing in our data, which is people recovering, people saying, I don't have chronic pain anymore. It's gone. That was just really astounding for me. Do you know why it worked for some patients but didn't work for other patients?
It's a great question. This is not a treatment that you can do to someone. It's a treatment that you do with someone. The person has to cooperate. They have to be motivated. They have to be willing to change some of their thinking patterns and emotional patterns. And the truth is, for many of us, changing our behaviors or changing our... our mood state, it's not easy.
pain or not pain. It's just hard to change ways that we've been accustomed to being for many years. I mean, is it possible that for some people for whom pain reprocessing therapy did not work, could there be some type of... underlying disease or condition that we just haven't quite put our finger on like we haven't figured out actually what's going on I've been Talking about it as categories of pain, but the truth is it's spectrums, it's dimensions.
And people may have relatively more or less sensitivity and they may have relatively more or less. say, arthritis in the body that's contributing to the pain. And one of the challenges here is that current technology can't measure someone's brain and say, I see it right there in your amygdala. We're not there yet. For some people, their chronic pain could be a combination from both an injury and changes to how their brain processes their bodily sensations.
And pain reprocessing therapy has its limitations too, because people's individual experiences are complicated. For some people, chronic pain is a big component of trauma and... history of deeply entrenched patterns of self-criticism. These make it a lot harder to just try to treat the pain in isolation. What we're finding is that for a number of people, you can't just
talk about the pain and expect everything to get better. But it will require a deeper dive into what's making them feel unsafe more broadly. and trying to help people resolve those other mental health challenges will be the key to helping their pain. So, Flora, there's a lot more to understand about how chronic pain and mental health influence one another. Obviously, this is just the beginning of this kind of research. It's really interesting. So what comes next?
So Dr. Ashar is really optimistic that the early success of pain reprocessing therapy actually confirms a lot of the past research into how changes in pain sensitivity lead to the development of chronic pain. And right now, clinicians are already using this type of therapy for other types of chronic pain beyond just the lower back pain we mentioned. And Dr. Shah and his team are about to start two new studies with patients who have chronic neck and also knee pain.
And there's plans a little further down the road to study chronic pelvic pain and fibromyalgia as well. So absolutely more data to come in the next couple of years. Shoshana, thanks for bringing us this story. You're so very welcome. Shoshana Buxbaum, producer for Science Friday. And that is about all we have time for. Lots of folks helped make this show happen, including... I'm Flora Lichtman. Thanks for listening.