The pain is all in your head (and researchers say that's OK)
- peter korn
- Portland Tribune - News
OHSU program moves beyond mirrors to retrain patients' brains
It's not that Beth Darnall is trying to put herself out of business. It's just that the Oregon Health and Science University pain psychologist and researcher thinks her patients can treat their chronic pain at home better than she can in her office.
A psychologist telling patients they need to see her less often may seen unorthodox, but then Darnall subscribes to a number of unorthodox beliefs. Among them: pain medication might be harming more than helping many women suffering chronic pain; health care practitioners should try to maximize the placebo effect in their patients; and the brain can and should be fooled with images that distort reality.
Darnall even has a book manuscript she's been shopping to publishers, titled 'Brain Tricks For Stopping Your Pain.'
Much of Darnall's philosophy stems from an experiment she completed in 2009 for one of the more unusual maladies around: phantom limb pain. What Darnall learned from treating amputees with mirrors opened up for her possibilities for treating all sorts of pain sufferers.
About eight of 10 people who lose arms or legs report chronic pain, sometimes severe, coming from the limbs they no longer have. The brain, according to Darnall, has had to 'reorganize' in response to the missing limb, often imperfectly.
'If you chop off a piece of the body, brain areas compete trying to reconcile the change,' she says.
Fifteen years ago, University of California, San Diego neuroscientist Vilayanur Ramachandran began using mirrors to trick amputees' brains into believing they still had the missing limb. In daily sessions, he would line up the intact limb with a mirror image visible to the patient, who would see two side-by-side healthy limbs. After four weeks of regular therapy, the patient's brain accepted what the eyes had been telling it - there were two functional limbs and no reason to feel pain.
In some of the patients, the phantom limb pain stopped, and stayed away. The brain, Darnall says, had permanently reorganized itself to believe there was no reason to feel pain.
Darnall, believing the therapy was as simple as it sounds, decided to take it one step further. She enrolled 40 amputees with phantom limb pain in her trial, taught them how to place the mirrors on their own, and sent them home to spend 25 minutes a day looking at two healthy limbs.
It worked - about half of her patients experienced significant pain reduction. Ten patients reported 'major pain reduction.' Two said their pain was gone.
'In the pain world that is considered very successful,' Darnall says. 'The beauty of it is, it's cheap, it has no side effects and no doctor's prescription.'
By way of comparison, Darnall says pain medication helps about 25 percent of phantom limb patients.
Tribune Photo: Christopher Onstott • OHSU pain psychologist Beth Darnall's unorthodox methods include rhythmically tapping on patient Fay Beck's hands to make Beck's brain more receptive. Beck says Darnall (left) has helped alleviate pain that countless physicians ad therapists could not.
Darnall continues to treat amputees, many of whom she helps by giving them a CD she has put together that shows them how to use mirror therapy on their own. In fact, later this year she will travel to Vietnam to introduce mirror therapy to a country full of people missing arms and legs who do not have access to therapists.
But Darnall's success with amputees spurred her into thinking about other ways the brain could be tricked into rejecting pain, with or without the use of mirrors. Techniques such as mirror therapy help patients change their brains quicker, she says, but the goal is the same as with traditional talk therapy.
'You're changing the way you think, you're changing your belief system about what's possible and developing a sense of control in the world you didn't have before,' Darnall says.
Pain researchers such as Dr. Sean Mackey at Stanford University School of Medicine have been using real-time MRIs to study how patients getting immediate feedback can learn to control the areas of their brain that manage pain.
Mackey took healthy patients and hooked them up to MRIs that could show in real time which areas of their brains were engaged when a heating device was placed against their skin to cause pain. Patients could see specific areas of their brains lighting up on a screen as their pain increased, and were instructed to control their emotional response to the pain and to focus their attention away from the pain.
Mackey's subjects learned to voluntarily control their brain activity and pain merely by using the real-time feedback - they were able to mentally change the areas of the brain that were lighting up even as the heat remained in place.
Next, Mackey enrolled eight patients who were longtime sufferers of chronic pain in a similar experiment. The heat source wasn't needed because they already had the pain, but by watching their brain patterns on an MRI, these patients were able to decrease their pain by an average of 64 percent.
Mackey calls his work 'a 21st century version of biofeedback,' but with the advantage of 'going right to where the pain is occurring.' Biofeedback teaches patients to control heart rate, respiratory rate and muscle tension, but not to directly focus on controlling pain.
Mackey says at this point his research shows that patients can decrease their pain, but he hasn't yet been able to show the change will last. This fall, he will start a study financed by the National Institutes of Health to look at whether patients with low back pain can learn to reduce their suffering long-term by using functional MRI.
Ultimately, Mackey says, patients could get a mix of therapies that teach them to control their pain, combining the real-time feedback he is studying with cognitive therapies that teach patients to control their thoughts, and drugs developed to increase the plasticity of the brain.
Work of researchers such as Darnall will be critical, Mackey says. He notes that a recent Institute of Medicine report on the state of pain found that 160 million Americans suffer from chronic pain - but there are only a few thousand pain specialists nationwide.
'Clearly there are not enough specialists to practice this,' Mackey says. 'We have to translate this knowledge into information more people can use to self-manage their pain. That's the only way we're going to be effective.'
Tribune Photo: Christopher Onstott • Donnie Morgan no longer feels phantom pain in his amputated left leg after using mirror therapy to trick his brain into thinking he has two legs. The mirror he once used for his daily therapy now hangs in the hallway of his trailer home in Milwaukie.
Power of belief
Darnall is particularly enthusiastic about Mackey's research reinforcing the idea that brains remain pliable and open to change throughout a lifetime. Up until the past 10 or 15 years, most physicians believed the brain was basically hard-wired early in life.
Darnall and other researchers have begun using mirror therapy to treat patients with a condition known as 'complex regional pain syndrome,' which often begins with arm or leg pain. People with the condition are often in so much pain that they cannot stand having their arm or leg touched.
Darnall uses mirrors to hide the painful arm, again presenting the patient with the illusion of two functional arms that can be moved or touched without producing pain.
Stroke victims classically lose function on one side of their body but not the other, so they also are natural candidates for mirror therapy, according to Darnall. The therapy can actually reactivate areas of the brain that were 'turned off' by the stroke, she says.
But the mirrors, Darnall says, are not the secret to rewiring brains. They are merely aids. The secret, she says, is being able to tell the brain how we want our bodies to be by visualizing a pain-free body.
Mirrors aren't applicable for stomach pain or back pain. But Darnall says similar results can be achieved by patients who use different techniques that help them find ways to increase the brain's plasticity. Some of these methods, such as deep breathing exercises, resemble yoga and meditation.
Another trick Darnall espouses to increase the brain's malleability involves cues that increase communication between the brain's left and right hemispheres. With some patients, she will simply alternate quick taps to their left and right knees. A more traditional method is for a patient to follow a therapist's finger as it moves from side to side. With other patients, Darnall uses sound, having them don earphones and listen to pulses alternating between ears.
All the tricks force rapid communication between the brain's left and right sides, and that communication opens a path making the brain more receptive to larger changes.
The key, Darnall says, is relaxation and the power of belief.
Recently Darnall treated a man who had suffered a stroke and subsequently felt pain along the right side of his body.
Darnall had the man hold a mirror in front of his body so that he could not see his right arm, but instead saw his left and a reflection of it where his right would have been. She had him make motions with his left hand, with his unseen right hand relaxed.
The mirror image was telling the man that he was moving both limbs without pain. In time, without the mirrors, the pain in his right arm receded.
Open to change
Much of the foundation for brain tricks like mirror therapy, Darnall says, came from researchers who began to scientifically study the placebo effect. Physicians have long recognized that patients who believe they will get well are more likely to get well. Patients taking placebos that they think are real medicines often report pain relief.
But it was only during the past two decades that researchers began to quantify how powerful the placebo effect can be. Some studies claim it can be responsible for as much as a 30-percent differential in healing between those who believe they will get better and those who do not.
The steps from placebo to mirror tricks to simply rewiring a brain with new messages are short ones, Darnall says.
'The most underutilized area of science and medicine is placebo,' she says. 'It used to be associated with weakness. I associate it with power. It perfectly exemplifies the power of the brain … if you believe it to be so, it is so.'
Cheryl Scott, a dean at Portland Community College, came to Darnall early this year after 15 years of suffering cluster headaches that had become increasingly intense each year. Scott has been to acupuncturists, chiropractors and physicians who had no explanation for the pain but prescribed pain medication. Nothing produced lasting relief.
Scott says she had a cluster headache as she showed up for her first visit with Darnall, who placed her in a chair and began alternately tapping on the backs of her hands. With her eyes closed, Scott listened to Darnall encourage her to relax. The pain began to lighten.
'Just listening to the words was nice, but it was the tapping, it was like it was imbedding it in my brain,' Scott says of the exercise.
Scott visited Darnall four times and was given a relaxation CD to listen to each day as she alternated tapping her own hands and focusing on relaxing all the parts of her body. Scott says her cluster headaches have gone from three to four episodes a week to one every 10 days to two weeks. She feels as if she has retrained her brain.
'I can't think of anything else that would be responsible,' Scott says. 'I'm a pretty practical individual. I'm not the kind of person who has ever done anything like this. But I also was open. I was open to the fact that I needed this to change.'
Courtesy of Brain Mind Institute at EPFL • In a Swiss version of the Avatar Experiment, patients can sense touch on their virtual reality avatars as if it were their own bodies being touched. The experiments have changed the way scientists view the potential of brain rewiring in adults.
• With the brain, it's what we see, not what's real
Tricking the brain is a relatively new approach, but research hinting that it could be done has been accumulating for years.
Oregon Health and Science University researcher Beth Darnall is fond of explaining a rubber hand experiment that researchers at the University of Pittsburgh devised in 1998. A woman with two operable hands sits in front of a table with her right hand in front of her and her left off to the side and out of her field of view. A fake left rubber hand is placed in front of her next to her real right hand.
When a researcher takes a hammer and hits the fake left hand, the woman reports pain.
Her brain has been tricked.
Another of Darnall's favorites is called the Avatar Experiment. Swiss researchers placed electrodes around the bodies of subjects who watched their own virtual images projected on a screen before them. When researchers poked the on-screen images, the subjects, who had not been touched, reported feeling the touch where their virtual-image avatars had been poked.
In some cases, subjects responded more to the touches they saw on their virtual images than to actual touches on their own bodies.
'The brain doesn't distinguish between what it sees and what is real,' Darnall says.
- Peter Korn