Chronic Pain Amplifies the Brain’s Reaction to New Pain

Chronic Pain Amplifies the Brain’s Reaction to New Pain

By Staff.

A new study in rats presented at the American Pain Society meeting shows that chronic pain in one body part may distort the intensity of how a key region of the brain perceives pain anywhere else.

Chronic pain in any one body part may distort the intensity with which a key brain region perceives pain everywhere else.

According to the researchers, their findings support the theory that chronic pain rewires circuits in a brain region called the anterior cingulate cortex (ACC) to increase “aversion,” the amount of attention paid to, and alarm felt about, any given pain signal. Most previous studies have focused on nociception, the intensity of incoming sensory signals instead of what the brain does once the signal is received.

“We pursued this study because of what we saw in the clinic, where patients with chronic pain, say in the lower back, report much higher than normal pain after surgery in the knee or abdomen,” says Jing Wang, MD, PhD, vice chair for Clinical and Translational Research Department of Anesthesiology, Perioperative Care and Pain Medicine at NYU Langone. “Our study results argue that chronic pain causes distortion in how the ACC calculates pain intensity with system-wide consequences.”

The new study is the first to show that chronic pain in one locale causes a greater reaction to pain throughout the body.  The researchers found that chronic pain in one limb in rats increased the aversive response to acute pain stimuli in the opposite limb.

To understand these mechanisms behind this, Wang and colleagues stitched into a certain spot in the DNA of nerve cells in rats the code for a light-sensitive protein. At the same time, the team implanted electrodes in the AAC to measure nerve cell activity. With these elements in place, the team was able to shine light on the ACC, which reacted with the light-sensitive protein to adjust the activity of nerve cells there as rats encountered painful stimuli, judged their intensity, and learned to avoid them.

The researchers found that chronic pain dramatically increases ACC activity, and that artificially increasing AAC activity made the brain region’s response to low intensity pain stimuli larger than normal, such that it “bothered” the rat much more than it should. By the same token, turning down ACC nerve cell signaling returned the aversive behavioral response, which had been amplified by chronic pain, back to normal.

Beyond pain processing, the study results imply that chronic pain can magnify responses to stimuli that are aversive but not painful, like the responses to light that worsen migraines. Furthermore, the ACC is known to be involved in emotional processes and connected to many brain regions. That, combined with the current study results, suggests that chronic anxiety and depression may also amplify the attention and alarm attached to pain stimuli that would otherwise be too small to bother us, researchers say.

In zeroing in on the ACC, the research team has also provided a rational target for technologies like deep brain stimulation and transcranial magnetic stimulation, which deliver electric current to reverse nerve cell signaling patterns that cause disease, says Wang. He and his colleagues are already working on related protocols designed to dial back the increased ACC activity linked to chronic pain, with clinical testing expected to begin in 2018.

You can read he study’s findings in eLife.

Subscribe to our blog via email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Authored by: Staff

newest oldest
Notify of
Christine Weber

I have complex Regional pain syndrome since a foot surgery 07 I experience Hyperalgesia
In the affective foot , I disagree with the findings with the above debunked as many victims of C.R.P.S. experience Hyperalgesia . Severe nurning pain with purple colored skin . I have been to the best doctors in Philadelphia Drexel University College of Neuropathic Medicine . Ketamine infusions with Low Dose Neltrexone is what has helped me the best . Some patients can not live a quality of life with out some amount of pain medicines . The war on patients with chronic pain is not justified it is cruelty to patients . Change the guidelines for dosages that doctors can prescribe quality of life is essential .

Sherry Sherman

This isn’t true and HA or Hyperalgesia has been debunked. It’s rare and only seen in a few cases. See link below:
https://www.practicalpainmanagement.com/treatments/pharmacological/opioids/longitudinal-study-long-term-opioid-patients
There’s one that specifically addresses Hyperalgesia by Dr. Forest Tennant and can be found on painresistance.net with pain patients radio day.

Susan D

Good Article. I didn’t even question the “whys”, but I’ve been aware since becoming a chronic pain patient that my ability to “stand” any acute pain has diminished.

Misti M

I have come to the conclusion that the only way that chronic pain patients will be seen as an asset to this country is if we made a MASS retreat to another country Mexico and started our own city with all of us and our families it would be a city take our disability money with us and hire new doctors and take our medical info with us … the medical community would be hurt by our retreat
We are not worthless minions not 1 person with any chronic pain condition should see themselves as such
we could jump start the economy in Mexico

Sandy Auriene Sullivan

I’ve noticed this…. if I can get the worst pain in my body moderate; the next in line can get a signal to the brain that it has pain too – ya know ‘hi! remember me’ pain.

That’s anyone. People with chronic pain have none stop all over pain though!

If a healthy person breaks a toe, leg and arm but the toe is snapped in half and the arm is a serious compound fracture while the leg is a serious fracture that needed pins. As they heal the one that hurts the most, like large stitches/staples and inflammation of the region – regardless of location is the one that the brain focuses on then the next then the next infinity in people with chronic incurable, barely manage pain.

That doesn’t mean we amplify pain to keep the cycle of being in pain going. Although our CNS feels like it is always on, occasionally the dimmer switch can be found through meds and treatments to dial down how loud it is; how hard it is pinging our brains saying pain, pain!!

[I describe pain in tones. high pitched, low baritones etc a high pitch is painful burning demanding the most attention while the low deep bass and baritones are the deep low throbbing or ache that has gone on so long it is almost white noise…]

Shaun

The title should add the words “in rats” otherwise it’s misleading to think this has anything to do with humans.

Woowoo

I recently had an access form but didn’t notice it until it was so bad I had to go on a heavy dose of antibiotics and have one tooth removed. It had affected 3 teeth. Thankfully the other two teeth recovered. I have regular radio frequencies for neck pain and associated headaches. I have a varied response each time. I have multiple areas of injury and while my pain is increasing I believe it’s from arthritis setting in. Each pain killer does it’s job in varying degrees. Surgery is unfortunately not an option. So I’ve been told..

Ibin Aiken

I think that the more “common” pain associated with our bodies ARE in fact more noticeable with insufficient prescribing of chronic pain medication used for a specific disease or injury simply because of the nature of opioid medication prescribed therapy. . Will our own bodies be able to manufacture, produce,our natural pain easement secretions for the more noticeable aches and pains with the CDC guideline” forced reduction of adequate medication for a very specific health condition? I highly doubt it and furthermore I, do not wish to be a guinea pig while suffering awaiting more “data” to be gathered! If for example, one “stubs” their toe accidentally, it is extremely painful but, in the recesses of the mind, we know that the injury WILL heal MOST likely to never to be noticed again after the injury…..heals. The same is not true of chronic pain. Once the injury or disease has been appropriately treated with ALL available medical knowledge and the injury or disease pain continues after proper treatment and heal time but,. STILL yields continuous pain, it becomes as much a mental condition healthwise; as much as a physiological health condition, to be treated. After ALL methods of treatment have been exhausted and pain still exists in enough severity to disrupt life, opioid pain medication needs be prescribed. The very nature of our bodies is to assimilate ANY type substance prescribed to help ease continued pain. After patients metabolism, weight, severity of injury and prognosis in regard to the painful condition has been evaluated, examined, and addressed by our doctors with “due diligence’ (common sense) as to how the health condition should be best addressed without harming the patient, We, just being forced to live in life long, continuous pain due to the us of illicit drug abuse curtailment is NOT justifable for an opioid prescribed “guideline”.The point being is that the treatment for chronic pain can be vastly different in the doctors opinion but, that discretion has been removed from the doctors authority. Asinine reasoning by ANY agency! A band aid is not placed on a broken leg. Pain, continuous, can and IS a real factor. The “guideline” treatment, the same maximum dosage “amount for one and all”, obviously not enough as per the CDC “guideline” is an attempt to slow or halt drug abuse needs be re-structured. I for one do NOT believe the “guideline’ is an adequate assessment reality for our physicians of medication prescribing for all health conditions.. It is sadistic, “over the top” policy to stop drug abuse The sufficient, effective opioid medication, after examination, evaluation, and specific tests for the individuals health condition have been quite adequately researched by our doctors. IF the only treatment for our specific treatment is reduction in dosage of opioid therapy medications and it is the ONLY means to sufficiently treat detrimental effects, then the CDC guideline needs to be amended or even abolished and the diagnosis of the health condition and prescribing of different and adequately prescribed medication… Read more »

Jean Price

I have a problem with theories which tend to imply those with long term pain REACT more severely to new pain, or are hyper-sensitive as a whole. I view this idea as basically unsound…certainly NOT TRUE across the board, not for ALL people who have pain. Yet, there are few things which are true for EVERYONE…whether we’re talking about pain or behavior! So I don’t mean this necessarily as a measure of the studies overall worth. It’s more just to point up how study outcomes and interpretations can really vary when we’re talking about pain…and individual bodies!! It also seems to me this idea of having “amplified reactions” could be viewed by SOME as more of a psychological/behavioral problem…rather than a specific natural and NORMAL physiological process. This could actually help pave the way then for some unfair PERSONAL judgements, instead of sound targeted physical medical evaluations! (Not to mention how this could also be used to fuel support for pain being veiwed (and coded for insurance!) as more of a mental health disorder!! Like the term “opioid use disorder” already implies! Scary! Especially since this would likely save various industries a LOT of money they are now spending for treating those with pain! And it would leave more people in pain without resources or options to help them!) So this seems like more of a misleading generalization to me….and even points to the problem now with pain care…how one size is supposed to fit ALL OF US! Yet, we know ONE PLAN CAN’T POSSIBLY WORK for such a variety of conditions and injuries and causes of pain! Plus there are way too many other variables for each INDIVIDUAL with pain to be taken into account…like the patient’s overall activity level, age, other medical conditions, general health, and support…which also affects their pain. I realize our bodies are designed to HAVE pain for a reason, and then to process this pain as a signal to let us know something’s wrong…so we can seek to remedy the problem, to change what we’re doing or be treated, Yet, when that something IS NOT fixable for any reason…our bodies naturally will continue to react physically, and keep the alarm bells ringing. It’s a physical reaction process! Our minds just can’t easily override such a basic biological protection system!! (If they could, just think of the possible disastrous consequences…especially when a new pain comes along to signal something serious, or an old pain is instead now signaling a NEW problem which quickly needs attention! Both of these scenarios can…and do… happen!). There is also a theory pain impulses will “wear a groove” over time, and will keep sending signals even after the problem is resolved. Yet few if any resolutions or interventions leaves us as functionally sound as before the injury or illness occurred. So, I’m unclear if this is really the case, at least in some situations. There are often areas damaged by treatments, which would tend to keep signaling a problem, even… Read more »

Rebecca Vigen

I completely agree with this. As a health care provider myself and also someone who lives with chronic pain, I recently experienced a change in my pain. I have lived with chronic pain for the past 1-2 years due to diabetic neuropathy. I recently went through a transmetatarsal amputation of my left foot which has caused new experiences in the pain I already experience. I have noticed that my neuropathic pain has intensified in my right foot. I also have bouts of phantom pain which has been an interesting pain experience to say the least. I would be interested to see more studies or research done on this topic.

Ray

Anyone with chronic pain should already know this it is ancient news

Teresa

I definitely believe this is true in humans. I was diagnosed with arachnoiditis in 2006. I have right leg, foot, hip and low back pain only on right side. My pain never goes below 3 on pain scale and goes to level 8 daily. I’ve noticed that any other pain I have is magnified. I strained the left side of my lower back last week. Just a simple strain. We all get from time to time. Hurt so bad I could hardly walk. Even simple things like stubbing your toe seem extremely exaggerated to me. I think the pain pathways are used so much and once you get into higher pain levels on regular basis. Its easier for your body to signal those higher levels. Its like that pathway is ingrained.

[…] to this article, a new study presented at the American Pain Society meeting shows that chronic pain in one body […]

Think of pain as an alarm bell. If you have a very loud alarm bell constantly ringing it would mask any new pain message. So your brain has to amplify the new pain message for you to hear it – it’s logical. The same happens when you take pain killers they just muffle the message so it has to ring louder.

I regularly help people switch off their old unnecessary pain messages using the same logic.

Yvetta Barbee

I think that’s partly true I have noticed the the reaction to new pain or issue is higher in the beginning until your​ body expects it. Than it’s a norm. But than these pains move around if you watch the region you can see it moving it’s travels like bolts of lighting and than there a bolt and it repeats. While other just lingering..I should have been a study.

I believe this is true. I’ve had severe back pain for the past year and I have noticed that certain other pain does bother me more. Another reason why we need more/quicker focus/treatment for chronic pain.