Experiencing pain? Sanjay Gupta explains why ‘It Doesn’t Have to Hurt’

Audio transcript

TERRY GROSS, HOST:

This is FRESH AIR. I’m Terry Gross. When you’re in pain, it can be hard to think about anything else. My guest, neurosurgeon and CNN chief medical correspondent Sanjay Gupta, writes that over the past few decades, we’ve learned more than ever about the true nature of pain. We better understand what causes it, what may best relieve it and what we can do to minimize or even eliminate certain types of pain. Many of those life-changing insights have not yet been made easily available to the public. His new book is an attempt to change that. It’s called “It Doesn’t Have to Hurt.”

Dr. Gupta is also the host of the podcast “Chasing Life.” He’s an associate professor of neurosurgery at the Emory University Hospital and is the author of four previous bestsellers. He’s won several Emmy Awards, as well as two duPont-Columbia Awards, the most recent one for his reporting on the medical use of marijuana – a subject we’ll talk about a little later in the interview. He also contributed to CNN’s Peabody Award-winning coverage of the devastation of Hurricane Katrina 20 years ago. Dr. Gupta, welcome back to FRESH AIR.

SANJAY GUPTA: Thank you. What a pleasure. I always enjoy our conversations. Thank you for having me.

GROSS: So I’ll start with something I’ve never said to a guest before, which is, tell us how you were impaled. This was just after your 12th birthday.

GUPTA: I was a kid. I was just after 12 years old – just turned 12. And I was running through the neighborhood on a really beautiful day – I still remember – and there was a fence. And I think it was sort of a wrought iron fence, and it had some spikes on top. And I had – you know, obviously knew this fence. Typically, I didn’t try and jump over it. I went around it. But this day, I just – I think I felt kind of invincible. And I decided to sort of try and vault myself over, you know, put one hand on and then vault your legs over. And when I tried that, I didn’t quite make it. And one of the spikes caught me on my side and went in the back area of my side and out the front. So I was sort of stuck there on this fence. It was just high enough that I could not put my feet down to sort of, you know, hoist myself off the fence.

GROSS: So it appears through your whole side?

GUPTA: Yeah. It was the skin, thankfully, as opposed to going into the chest or into the abdomen, which would have been much worse. But it was sort of a classic in-out sort of injury. And the story is interesting because the – first of all, I was there for a couple of minutes before anyone saw me, which was really a very strange feeling. You know, I knew somebody was going to find me, but I think for a moment as a 12-year-old, I thought, what if they don’t? And – but eventually, a neighbor came out. And around the same time, my mom sort of – I don’t know how she became aware, but she kind of heard and she came over. And the neighbor went to go get this big sort of wire cutter thing, and he was going to basically cut it. But I couldn’t wait, actually. So with my mom’s help, she put her foot down. I mean, she put her hands down so I could put my foot on her hands, and I hoisted myself off the spike. So I actually came off the spike on my own before he cut it off.

GROSS: Ouch (laughter). And you write that the tissues in the torso don’t have as many nerves and as much sensitivity as other parts of the body.

GUPTA: Yeah. This was, I think, the first time I started sort of thinking about pain in a different way because, first of all, and I can tell you what it felt like, which was very different than what I would have imagined it to feel like before it happened. But yeah, one of the things is that the skin on the back, it has fewer of these nociceptors, these receptors that will actually transmit pain. And by fewer, it also means that they’re less dense over an area. When you have a higher density of nociceptors, that’s when they’re going to be more sensitive. And they’re transmitting signals very quickly ’cause they’re so close together, jam-packed together.

When those nociceptors are further apart, you have less sensation. You have less what is called two-point discrimination, so your ability to tell the distance between two points is much greater on the back. The two points have to be much, much further apart before you can really tell that there’s two points. And it didn’t hurt as much as I think many other parts of the body would have.

GROSS: OK. So now that we’ve established that you’ve experienced pain…

GUPTA: (Laughter).

GROSS: …What do you mean when you say that pain is created by the brain? In your case, pain was created by a very unnatural injury. But explain that the pain is created by the brain.

GUPTA: Whenever we have some sort of thing that happens in the periphery of our body – in this case, it was my back – signals are then sent to the brain to basically be processed, to be translated and to be interpreted in some way. When those signals go up – it’s kind of like the brain is, you know, rapidly scrolling a social media feed and may say, OK, this is not that important. This is not that important. This is not that important. Oh, wait a second, this is incendiary, this particular post. Let’s pay a lot of attention to that.

And it determines at that point, is this real, No. 1, or is it not? Is it noteworthy, meaning, how – you know, how significant is it? And what should I do about it? There are certain things that happen before you get to the brain, which is that you might have – like, if you touch a hot pan, your hand might jolt away from it. That’s happening reflexively. There are certain nerve fibers that do that. But when it comes to actually determining if something hurts and how much, that is the brain. The brain determines whether or not you have pain.

GROSS: The brain sometimes makes mistakes in its interpretation…

GUPTA: Yeah.

GROSS: …Of pain too, and sometimes it sounds the alarm too loud and too long. How does the brain make mistakes, and what kind of pain does that lead to?

GUPTA: One of the best examples of how the brain can make a mistake is phantom limb pain. In that case, a limb doesn’t even exist anymore…

GROSS: It was amputated.

GUPTA: …And yet it still hurts.

GROSS: Yeah.

GUPTA: It was amputated, and yet it still hurts. I think that’s one of those sort of insights about the brain that I think led to a lot of learning about what exactly the brain’s role was with pain. If the brain’s the decider of pain, can it create pain as well? And the answer is yes. Referred pain is another sort of mistake. So some people may be having what should be chest pain from a heart attack, but instead of having chest pain, they may have jaw pain. They may have just left arm pain. And some of those are common referrals. We know left arm pain, for example, is very associated with potential heart problem. Doctors are sort of trained – same thing with jaw pain.

And then there’s sorts of things where, whatever the reason may be, the brain continues to play the loop of pain over and over again. I guess that’s not so much a mistake as it is some – maybe some sort of glitch, where the pain loop doesn’t stop and it just gets recycled over and over again. And that’s chronic pain. So those are some of the ways that the brain can sort of either mistake or misinterpret the signals and the pain.

GROSS: So, you know, a lot of times someone will go to see a doctor, and they have chronic pain, but there’s no evidence of what’s causing it, and the injury has healed. So that’s a kind of brain misinterpretation?

GUPTA: Some would argue that there is a reason, and it may have to do with everything from adverse childhood events to even more recent trauma to a history of depression or anxiety. As someone said to me – I think it was Mark Jensen at Mayo Clinic – that chronic pain never occurs in isolation. It always occurs with baggage attached, and that baggage could be depression, could be anxiety, could be adverse childhood experiences, could be poor sleep. It could be things that maybe seem more trivial. Could be you’re having a really bad day, and something that wouldn’t have hurt so much hurt a lot more because you’re having a bad day. Maybe you had a bad call with your parent. Whatever it may be, all these things – some more clear, some more arbitrary – seem to have some influence not just on your pain, but how much something’s going to hurt and how long it will hurt.

GROSS: So one of the main themes of your book is, if the brain interprets pain, can we get the brain to interpret it differently, or at least turn down the volume of the alarm that it is sending? Do you believe the brain is really capable of being rewired like that?

GUPTA: Yeah, I really do. And I’ve seen it firsthand. The idea that meditation could provide relief – maybe not super durable. It’s not something that lasts forever. But the idea that you could take someone’s pain score from really terrible pain to a 0 out of 10 – and I’m not exaggerating – but a 0 out of 10 for the 30 minutes that they are meditating, I think, is real proof of concept that there’s a lot that can happen within the brain that can be trained without drugs, without surgery. So, yeah, I think the brain can be trained that way.

GROSS: Do you have a scientific medical explanation for why meditation can decrease pain for at least an interval of time?

GUPTA: Dr. Eric Garland is probably the nation’s leading expert on this. He’s out of the University of California San Diego. And I spent a lot of time with him and asked that same question. And I think we don’t know is the most honest answer. I think where people sort of circle around is this idea that distraction could be one component of it. You know, with pain, people are usually hyperfocused on a particular sensation. Being able to take them out of that hyperfocus can be really helpful.

There’s other people who believe that you’re actually decreasing the activity in certain areas of the brain. Specifically, an area known as the anterior cingulate cortex, which is an area where pain is processed. Pain is processed in many areas of the brain, but that’s one of the primary areas. But we don’t know for sure. It would require, I think, a lot more testing to really, you know, look at people’s brains while they meditate and understand what’s happening. And even then, the answers may not be clear.

But what I think is clear, based on lots of data, is that people can get significant relief from meditation. And I even asked Dr. Garland to, like, give me context for what that means, significant relief. I mean, we can put numbers on it. But what he showed and what his most recent paper described was basically similar to 5 milligrams of oxycodone. That’s what meditation can do for you. Five milligrams of oxycodone is very effective. It also doesn’t last forever. It has a half-life. Meditation is sort of the same way. It doesn’t last forever, but you can reduce your pain scores to near zero for a period of time.

GROSS: You actually meditated with the Dalai Lama. I assume you were reporting on him, which is how you got to get the invitation to meditate with him. And you were very self-conscious and distracted because you were not only meditating, you know, you were doing it with the Dalai Lama. You reluctantly admitted that to him after the session was over. And tell us what he said to you.

GUPTA: (Laughter) He told me he also had a difficult time meditating, which really surprised me. I mean, you know, he’s the Dalai Lama. He’s been meditating, you know, basically his whole life. And he’s a master meditator. He gets up, I think, 3:30 in the morning, and he meditates for a couple of hours before he starts his regular day. And that was the time that I was meditating with him. But he sort of conceded that it can be challenging for people to meditate. You have to be very intentional about it.

GROSS: Well, let’s take a pause here because I have to reintroduce you and take a break. My guest is neurosurgeon Sanjay Gupta, who is CNN’s chief medical correspondent. His new book is called “It Doesn’t Have To Hurt.” It’s about pain and pain management. We’ll talk more. After a break. This is FRESH AIR.

(SOUNDBITE OF ROBBEN FORD AND BILL EVANS’ “CATCH A RIDE”)

GROSS: This is FRESH AIR. Let’s get back to my interview with CNN chief medical correspondent Dr. Sanjay Gupta. He’s a neurosurgeon. His new book about pain and ways to control it is called “It Doesn’t Have To Hurt.”

One of the points you make in the book is that researchers have found that pleasure and savoring, savoring food, savoring pleasure, making sure you make some space for pleasure or savoring in your life, that it isn’t a waste of time, that you’re actually rewiring your brain and countering pain in ways that strengthen with practice. Can you talk about that a little bit, about what that might mean?

GUPTA: Sure. I think our default position, probably, as humans is to be creatures that have gratitude and savor and want to experience pleasure. That’s no surprise. But what I think is really interesting is that we have this system within our body. The endogenous opioid system, which is endorphins, which means endo, which means inside the body, and phins, which is morphine. This is like our internal morphine system, endorphin system. We can activate this system in all sorts of different ways. And by activating, I mean exactly what it sounds like. You just basically release a lot of these endorphins, these basically personalized morphine molecules all throughout your body.

And one of the ways that they have shown can really facilitate that is to not just practice gratitude, but to actively practice gratitude, meaning actually savor something. I’m not just grateful for this ice cream cone. I’m like, just so enjoying this ice cream cone. I’m not just grateful for being able to look at this sunset. I am gazing at every different color in the sky and just taking it all in.

It’s a very active form of gratitude, and it seems to be very associated with basically activating the endogenous opioid system, which is really fascinating to me. Some people would refer to this as sort of the mechanism behind placebo effect. Others say the placebo effect is going to be a lot more intricate than that. But when it comes to pain specifically, I think we know all these different things that we’re talking about, whether it be meditation, whether it be savoring – all these things mechanistically probably have some component of activating this really wonderful, intricate system in our bodies.

GROSS: I guess it also teaches the person who is savoring or having pleasure to distract themselves from pain because just as pain distracts you from the things you need to do, having pleasure really distracts you from the pain.

GUPTA: Yeah. I think what’s becoming increasingly clear – that these types of, you know, feel-good transmitters and endorphins are released in response to certain things that happen in our lives. You know, even going back to when I impaled myself on that fence, I think what was so interesting to me, and I was only 12 years old at the time, but when I reflected on it, it obviously hurt when I got impaled. But then I was basically pinned there on the fence for several minutes. And you know what, Terry? After a while, not only did it not hurt as much, I actually started to feel strangely a bit of euphoria…

GROSS: Really?

GUPTA: …Which is – yeah, which is really weird. But I think what happens for some people, and probably I fit into this, is that when you do have an injury or, you know, whatever might happen to you, if you activate your endogenous opioid system, for some people, it reacts really vigorously, like, really, really churns out a bunch of endorphins. And so you could have this really sort of ironic situation where you get a terrible injury, and you’re almost laughing. You’re like (laughter), oh, my God, you know? And it’s – I think it’s a very protective sort of response from the body. And not everyone responds the same way. Some people probably make fewer endorphins. And maybe if it had been raining on me and I hadn’t eaten well that day, maybe I would’ve made fewer endorphins. But for a period of time, I really had no pain. In fact, I remember I reached behind with my hand at one point to feel the spike and convinced myself that it was still there.

GROSS: Are there any medications that exist or that are in development that could turn on the body’s natural opioid system and release more endorphins?

GUPTA: What we’ve done is basically try to give endorphins, right? We’ve – instead of saying exactly what you said, which is can you harness the body’s own EOS, endogenous opioid system? Instead, we said, oh, the body makes endogenous morphine. Let us synthesize this molecule on our own. Let us create a drug that essentially attaches to the same receptors that these endorphins do, the mu receptors in the body. And that was sort of the genesis of opioids. You know, so many techniques and medications that we use in real life take their inspiration from our human body, and that’s one of them.

So we give opioids, probably more so than focusing on teaching the body to release its own opioid system. And while they both may have opioid in the name, they’re very different. One thing is that with your own opioid system, it is very, very sensitive. So it can turn on and it can turn off really, really well. So instead of having the lingering sort of side effects of opioids and sedation and all these other things, the opioids that you make yourself can just be washed away very, very quickly. The second thing is that impact on mood. It can actually make you euphoric. It can really improve your mood. And the third thing is that people with opioids, often it does not suppress their memory. In fact, it may actually worsen it. And worsen it, in this case, means over-remembering. So people who take opioids long term might actually start to have more pain because they become increasingly challenged to forget their pain.

GROSS: Right. So in answer to our researchers trying to develop an external form of endorphins, your answer is, yeah, morphine, and it didn’t work out very well. But that’s why pleasure is kind of like a prescription right now.

GUPTA: Yeah. I think pleasure, savoring – we know these things will release more opioids. People tend to feel better. Their pain tolerance goes up, and their remembering of unpleasant things goes down.

GROSS: Right.

GUPTA: So all these things sort of happen. I always say, if the endogenous opioid system didn’t exist, women would probably never have more than one child. You know, it can be a painful experience, but those opioids help with the pain. They help with the mood. And then that memory component is so fascinating to me. It can actually inhibit your memory. Like, I talked to my wife about this, Rebecca. We have three girls. And she’s like, yeah, you know, I had the baby. I, you know, just – by time we’re having the second one, it wasn’t, like, something she reflected on and was traumatized by. That’s, like, one of the most significant things that happens in your life. How could you possibly forget that? And maybe it’s – forgetting’s not the right word, but how could you not remember it really vividly? And I think that’s not by accident. I think that’s really our own endorphins sort of doing their job in terms of pain, mood and memory.

GROSS: OK. We need to take another break here, but there’s plenty more to talk about. If you’re just joining us, my guess is Dr. Sanjay Gupta, CNN’s chief medical correspondent and author of the new book “It Doesn’t Have To Hurt.” We’ll talk more about pain and pain relief after a short break. I’m Terry Gross, and this is FRESH AIR.

(SOUNDBITE OF SAINT SINNA AND CREEBO LODI SONG, “REAL FLOW”)

GROSS: This is FRESH AIR. I’m Terry Gross. Let’s get back to my interview with Dr. Sanjay Gupta. His new book, “It Doesn’t Have To Hurt” is about pain, how the brain sounds the alarm through pain and how the brain sometimes misinterprets the signals it gets and sends alarms that are unnecessarily loud and misleading. He also writes about treating pain from over-the-counter standbys like Tylenol, Advil and Motrin to new non-opioid medications, including electric medicine, new medications and how meditation and other techniques can help you retrain how your brain and how you process pain.

Let’s talk about the latest understanding of inflammation and anti-inflammatories, and that would include medications like Advil and Motrin. Inflammation is an essential part of healing after an injury. It protects the injury. It’s like putting a protective covering over the injury. But after a while, it seems like part of the problem is the inflammation itself. Sometimes it just won’t go away, or it just lingers too long or gets too large.

GUPTA: I think, for the most part, inflammation has sort of gotten a bad rap. I think that the idea that I don’t want to have inflammation, I’ll do everything I can to get rid of inflammation if I have some sort of injury, that has been, I think, the prevailing wisdom for a long time. And I think it’s understandable. I think when you look at a sprained ankle, for example, and it looks swollen and red, the idea that I want to get rid of that that’s associated with my pain makes intuitive sense. I think the idea that that inflammation serves a real purpose, that not only is it sort of helping protect the site of injury but also sending all these various molecules to the site of injury to help with the healing, I think, is also what’s happening at that point.

So there was a study that came out that basically was trying to figure out who is most likely to have chronic pain after injuries. So if you look at the sprained ankle example, who is most likely to still have pain three months later? And interestingly – and the researchers weren’t looking for this – what they found was that people who had the lowest levels of inflammation at the time of injury were the most likely to have chronic pain. So low levels of inflammation were linked to chronic pain, not high levels of inflammation. And it was really relevant, I think, for people, especially in the sports world and orthopedic surgeons and physical therapists to sort of look at the guidance that had typically been given to people, which was do everything you can to decrease inflammation.

GROSS: So some researchers are recommending now not taking anti-inflammatories right after an injury. When do researchers suggest that you do take anti-inflammatories?

GUPTA: I think it’s if you can’t tolerate it. That’s the thing about pain is that everyone’s threshold is going to be a little bit different. Again, if you haven’t broken it, I’m telling you it’s better to mobilize and not try and decrease inflammation. I think for a lot of people, they think they need to take anti-inflammatories. Oh, this is bad. I got to treat that. That inflammation’s not good. It’s hurting my body. But if I flip the script on you and I say, it’s not bad for your body. That is exactly how your body is supposed to work. This is your body doing its job.

GROSS: This may be a good time to mention that acetaminophen, for example, Tylenol, is not an anti-inflammatory.

GUPTA: That’s right.

GROSS: In your book, in describing what kinds of problems could be treated with acetaminophen, like Tylenol or ibuprofen, like Advil and Motrin, you have under both categories, under both types of pills that they’re really not for nerve pain. Why not?

GUPTA: Nerve pain or neuropathic pain tends to be a different sort of pain. Again, with anti-inflammatories, I guess it’s inherent in the name, the way that it works – Tylenol can help decrease inflammation, but in a totally different mechanism. It’s very good at reducing fever. Nerve pain really seems to be something that has to do with an abnormality of the way the nerve’s actually conducting signals. So, for example, when someone herniates a disc in their back or their neck and it puts pressure on the nerve, the nerve is not conducting the same way. It may be over-sending some signals or under-sending other signals. And what you’re really trying to do in that situation is take certain meds that might balance out that nerve conduction again. And that’s a different class of medications. There are several classes that can do this, but not typically anti-inflammatories.

GROSS: You know what I sometimes wonder? Can a numbing agent like lidocaine train the brain to think like, oh, there’s no longer pain, so I can turn the pain signals – like…

GUPTA: Yeah.

GROSS: …The unnecessary pain signals, from chronic pain. I can turn them off now. Can you trick a brain with a numbing agent?

GUPTA: This is a – it’s a really interesting question. And lidocaine is a good example of this. So Lidocaine is what’s called a sodium channel blocker. You know, whenever there’s signals being transmitted in the body, the way those signals move is through changes in ions – sodium, potassium. Ions like that. If you can block certain – a certain of those sodium channels, you can inhibit certain sensations. In this case, pain or sensation overall because lidocaine makes you numb. It’s not just taking away pain. I don’t know that there’s any indication that they will necessarily train your brain in some way to have any benefit beyond the time that the lidocaine is there in terms of chronic pain.

You can get rid of it for a period of time, and we use lidocaine to basically convince ourselves as surgeons that something that we’re about to do is going to be beneficial. So someone who has trigeminal neuralgia, I don’t know if you’ve ever heard of that, but it’s lancinating face pain. Tic douloureux, it’s called, and it’s one of the worst pains I think a human can actually feel. Just these lightning bolts of pain in your face. But anyways, one of the things that we’ll do is we might inject the root of the nerve with some numbing agent like lidocaine and basically see if that takes away the pain. And if it does, that gives us an indication that it may be OK to heat up that area of the nerve or to use chemicals to sort of make that nerve not conduct anymore. But that’s what those types of numbing agents are good for.

GROSS: Well, it’s time for another break, so let me reintroduce you. If you’re just joining us, my guest is neurosurgeon Dr. Sanjay Gupta, CNN’s chief medical correspondent. His new book is called “It Doesn’t Have To Hurt.” We’ll talk more after a break. This is FRESH AIR.

(SOUNDBITE OF LOOP 2.4.3’S “ZODIAC DUST”)

GROSS: This is FRESH AIR. Let’s get back to my interview with CNN chief medical correspondent Dr. Sanjay Gupta. He’s a neurosurgeon, and his new book is about pain and ways to control it. It’s called “It Doesn’t Have To Hurt.”

While you were writing your new book, a non-opioid pain medication was approved by the FDA. Tell us about it.

GUPTA: Yeah. The medication is called suzetrigine. It is a new pain medication. And interestingly enough, it is the first new pain medication that was approved by the FDA in the United States since 1998, which I found really remarkable. I mean, the last one was Celebrex. And just to give some context, the FDA will typically approve 40 to 50 new drugs a year. But for pain, which is a condition, chronic pain, that affects 20% of the population and, according to some of the statistics we saw, is the fastest-growing condition now in the United States, faster than cancer, diabetes and dementia – it’s pretty remarkable that we hadn’t had a new option for pain. But suzetrigine is that new option, and it is a fascinating story of how it came about.

There were these families of circus performers in Karachi, Pakistan, that got the attention of researchers, whatever, 25, 30 years ago. And they saw that these circus performers were able to do all these remarkable things. Like, they could put sharp things through their appendages, and they could walk on hot coals and do all that sort of stuff. But what they found was that when they were doing this, they could feel the coals on their feet, and they could feel that they were hot. They just didn’t have pain. And that’s very different than what we were just talking about with lidocaine, which basically numbs you. So when you’re numb, you just have no sensation. Here, they had sensation. They just didn’t have pain. And that was pretty striking because it gave these researchers a clue as to which sodium channel blocker may be important when it came to just targeting pain and not sensation overall. They studied this family. They found that they had a gene in common. I think it’s called SCN9. And basically, for 25 years, these researchers tried to replicate what that gene was doing in the body.

Now, one of the big challenges of creating a medicine like that is something you alluded to earlier, which is that you didn’t want to take away pain forever. Pain has utility. It can keep you safe. It can teach you lessons. So they wanted to create a half-life for the drug. So they basically now have an oral formulation. I think it’s twice-a-day formulation to basically try and treat pain, something that, you know, they hadn’t had a new therapy for in over 25 years.

GROSS: Let’s talk about cannabis as a pain medication. You’ve done extensive reporting on cannabis as medicine. What are some of your takeaways about the use of it for pain?

GUPTA: We spent a lot of time looking at the literature around cannabis. And I walked into it thinking that if I really examined all this literature, there was going to be a pretty compelling case made for using cannabis for all sorts of different pains but mostly neuropathic pain, this type of pain where the nerve’s just not conducting well and either over- or under-conducting, and that’s causing pain. And I walked away not as impressed, to be quite honest, as I thought I would be. And this is just the data talking. I will say it’s hard to collect this data when you’re dealing with a substance that has been a Level 1 substance in the United States for a long time. It’s just really hard to get good studies.

GROSS: It’s hard to get funding probably, too, right?

GUPTA: Yeah. And then there’s a lot of stigma attached to it, so people don’t volunteer for the trials, whatever it might be. But having said that, the best available data seemed to suggest that for about a third of people, it could be pretty effective and maybe, in some cases, as effective as the best other options for that neuropathic pain. Terry, for about two-thirds of people, it really did not seem to be that effective. And this is the case, I think, for about a third of people. They get significant benefit, and we don’t quite know who those third of people are. We don’t know what makes them different than the other two-thirds that they’re getting that kind of relief.

GROSS: Is there any evidence that it might be the placebo effect?

GUPTA: Yeah. I think that they’re looking at all sorts of different things, including placebo effect. I think one of the researchers that I talked to – I think it was Julie Holland. She kept making this point that I thought was a really good point, that expectations and experience are inextricably linked, especially when it comes to pain, and the idea that if you really expect something to work, it’s more likely to work. And that isn’t necessarily your body or your brain playing tricks on you. That is probably, again, harnessing that endogenous opioid system. You think it’s going to work. Your body’s like, oh, yeah, I’m about to get relief. Wow, I’m already feeling it, you know? And that, in part, could be those endorphins starting to really ramp up.

GROSS: Another way of kind of retraining the brain is deep brain stimulation, which uses electric impulses in parts of the brain, in relevant parts of the brain. It’s used now for Parkinson’s disease. There’s, like, a little device that’s implanted in the appropriate part of the brain, and there’s a remote control. You can turn it up or turn it down. So how is that being used in pain relief, or is it just in the real beginning stages?

GUPTA: Deep brain stimulation’s been around for a long time. And, you know, Parkinson’s was one of the things, but they also treat things like obsessive compulsive disorder now, even with – Tourette’s, things like that, with deep brain stimulation. It’s pretty fascinating. The idea of using it for pain sort of came about in a very interesting way.

I think one of the big questions neuroscientists have been percolating on for a long time is, we know pain is processed in the brain. Is there a way to figure out where and how it’s processed in the brain and also to measure it in some way? Right now, we’re primarily relying on, you know, smiley or frowny faces for patients to tell us how much pain they have. But is there a way to objectify that in some way?

And I think that’s really how these researchers, Prasad Shirvalkar and others at UCSF started approaching this, was to say, OK, these patients who have pain – and these were the worst of the worst patients. They had pain that was so refractory. They’d had sometimes dozens of operations, spinal cord stimulators, taking many generations of pain medications, and they just weren’t getting relief. They were the ones who qualified for the trial. And the trial basically consisted of putting a bunch of stimulators all over the brain, left side and right side, and basically just listening to the brain. When the person had pain, they recorded it, and they would do this for months. And they would basically say, OK, whenever the patient has pain, what happened in the brain at that point? Was there a transfer of energy somewhere? Is there something to see?

And using, you know, machine learning now, being able to analyze a lot of that data – because it’s a lot of data. You have 84 billion neurons in the brain. They were able to find those areas, in some ways measure them, seeing how much energy was actually changing in that part of the brain, which gave some sort of correlation with the significance of pain or the severity of pain. And they even got to the point where they could start to predict that change of energy before the patient felt it. And they even got to the point where they could then interrupt it, much like you do with Parkinson’s.

You gave a little jolt of electricity at that point, and you basically interrupt that pain signaling at that point in the brain. It was proof of concept, I think, to your fundamental question, which is, not only is this the formative stages, this isn’t something that’s ever going to be, you know, for the masses. No one is suggesting that brain surgery, which is what these patients had, is going to be the answer. But I think what it has proven is that pain is very much in the brain. And we can objectify it in ways that we did not fully appreciate before.

GROSS: That’s fascinating. Is AI being used as part of this to process the data?

GUPTA: Yes. I think if you talk to these researchers, I don’t think they could’ve done this probably without at least these large machine learning models. It is so much data. I mean, they had some idea where pain processing is likely to occur. There are some areas of the brain that are more likely to process pain than others, but there is no single pain processing center. So they needed to look all over the brain and then just spend this time correlating lots and lots of data with all these energy transfers that are happening in the brain, because your brain is constantly communicating.

And I got to tell you, I got to spend time with a patient who got tremendous success with this strategy that I’ve described. And he’s had terrible pain for decades. You know, it’s the kind of pain I’m not sure I could’ve tolerated in my own life the way he described it. Just like these snakes constantly biting his feet and razor blades all the time. He had a condition known as CRPS, chronic regional pain syndrome.

And he’s in the hospital, and he’s got the stimulator in. And he’s, you know, in the middle of a patient visit. And all of a sudden, he goes, whoa. And they said, what? He goes, I don’t have pain. The veil of pain just went away. I’ve had this veil over my face and over my, you know, brain for decades, and it just got lifted. I don’t have pain. It was the wildest thing. I don’t know where the research goes in terms of what this is going to mean for the masses. But it was really, really amazing to see that kind of relief.

GROSS: Well, on that note, Sanjay Gupta, thank you so much for talking with us.

GUPTA: Thanks, Terry. I always look forward – I write books just so I can have these conversations with you.

(LAUGHTER)

GUPTA: I really appreciate your time.

GROSS: I appreciate yours. Thank you so much and be well. Thank you.

Sanjay Gupta is a neurosurgeon and CNN’s chief medical correspondent. His new book about pain is called “It Doesn’t Have To Hurt.”

After we take a short break, TV critic David Bianculli will review the new HBO crime series, “Task,” by the creator of “Mare Of Easttown.” It stars Mark Ruffalo. This is FRESH AIR.

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