Pain May Be in the Brain, But It's Still Real


May 13, 2005 -- -- If your doctor tells you that your chronic pain is in your head, don't be offended. You may be getting the latest in medical advice.

For too long, some doctors and psychiatrists say, the link between emotions and pain has been ignored or pooh-poohed by the medical profession. It has left some people with chronic pain to suffer, they claim, because the symptoms of their problems are being treated without the causes being addressed.

"Pain actually is an emotion, so clearly there is a connection," said Alex Zautra, a professor of psychology at Arizona State University, where he leads a research team whose work is centered on chronically ill patients with muscular-skeletal illnesses such as rheumatoid arthritis and fibromyalgia.

"Pain is the way the mind responds to trouble inside the body," he said. "Emotion is the same way. Whether you feel love or sadness is also a response to something you feel outside the body. With pain it is a closer-in response, to something inside the body, but it is a response in an attempt to learn about and motivate recovery."

A recent study in Europe found that more than 40 percent of people who suffer from depression also suffer from chronic pain, and a study conducted by the Stanford University School of Medicine in the United States, which has not yet been published, found similar results, said Dr. Alan Schatzberg.

Other studies have found even higher rates of co-morbidity between depression and chronic pain -- as high as 60 percent or 70 percent, depending on how chronic pain was defined, Schatzberg said.

"It is not a chance finding," he said. "I think it is a real finding."

The reason for the connection may be that the neurochemical problems responsible for the depression may also be responsible for the patient's chronic pain.

Some doctors now prescribe certain antidepressants for people who suffer from chronic pain but apparently have no physical cause for the pain, even in people who do not suffer from depression. Duloxetine, for example, which is marketed as Cymbalta by Eli Lilly and Company, is the first drug to be approved by the FDA for treatment of diabetic peripheral neuropathic pain.

When discussing these findings, doctors and psychiatrists alike say it is important to understand that it is in no way a dismissal of the suffering endured by people who might not seem to have a physiological cause for their pain. Even when there is a clear physical cause, pain itself only occurs in the brain, they say.

"Pain is in fact all in our heads, but we have to be sure when we say that, we say it without the usual pejorative context, implying that pain is made up," said Dr. Sean Mackey, the co-director of the Stanford University Pain and Clinical Research Center. "An injury out in our arm is not pain, that is 'nociception.' The perception of pain occurs in the head."

People suffering from depression are not the only ones who suffer chronic pain without having any corresponding physical cause.

Some people who have had a stroke will experience fierce pain in an arm or leg without having any injury there. People who have had a limb amputated sometimes feel pain in the missing limb. And people with post-traumatic stress disorder or who have suffered emotional trauma or been the victims of early childhood abuse have all been found to be more susceptible to pain and more likely to suffer chronic problems such as lower back pain.

"Dealing with psychology is part of dealing with chronic pain. It doesn't mean you're crazy if you have chronic pain," said Dr. Joel Saper, director of the Michigan Head Pain and Neurological Institute in Ann Arbor. "It's about a bilateral dynamic. Your emotions can make you vulnerable, and pain can affect your emotions."

He pointed to work by Dr. Irene Tracey of Oxford University, who used brain scans to discover that people's pain intensifies when they think about their headaches. Tracey's work has confirmed that fear and anxiety make pain worse, while pleasurable or distracting activities such as listening to music or watching a movie can actually reduce the amount of pain a person feels.

Catherine Bushnell, a researcher at McGill University's Center for Research on Pain in Montreal, using brain imaging, has also shown that being distracted has a real effect in decreasing the intensity of pain signals in the brain. She and her colleague, Chantal Villemure, subjected volunteers to slightly painful pulses of heat and, in other tests, they had them listen to different tones at the same time.

The subjects reported that their perception of pain diminished when they were listening to the tones -- and brain scans revealed that pain signals in their brain actually lessened as they listened to the tones.

"This means that things like having family around constantly asking how you feel can actually draw more attention to your pain and enhance it," Bushnell said.

Emotion can also enhance or decrease people's perception of pain, her studies show. Bushnell and Villemure demonstrated that subjecting people to pleasant and unpleasant odors influences how much they are bothered by pain. Pleasant odors eased the sensation of pain while unpleasant smells made the pain feel worse. Bushnell's and Villemure's work is published in a recent issue of the journal Pain.

This may be because one part of the brain, the anterior cingulate cortex, seems to be involved in both the processing of emotions and of pain, Mackey said.

The question, he said, is whether the ACC acts as a "gatekeeper," sorting through different stimulae and letting more of one through while limiting others, or acts more as an amplifier or soundboard, turning up the volume on one stimulus -- perhaps something pleasurable or interesting -- and turning down the volume on another stimulus that is less positive.

"We're trying to tease it apart," Mackey said. "I honestly don't think we have the answer to that question."

And when it comes to putting all this into practice to help patients, doctors and psychiatrists admit they are still learning.

"One of the problems with this field is that we are working with a lot of speculation, because there is not a lot of research on the link between emotion and pain. But common sense tells us there is a link," said Dr. Janina Fisher, a psychologist who practices at the Center for Integrative Healing in Watertown, Mass., and teaches at The Trauma Center in Brookline, Mass., and Harvard Medical School.

She said for too long there has been a split between the medical health and mental health professions, training physicians to work solely on the body and therapists to work only on the mind.

"Most health professionals do not make the mind-body link," she said.

One place that does is the Sensorimotor Psychotherapy Institute in Boulder, Colo., founded by Dr. Pat Ogden in 2000. Fisher trained there after 18 years as a clinical psychologist.

"What made me interested was the failure of talking therapies to resolve the effects of psychological trauma," she said.

Sensorimotor psychotherapy attempts to make the connection between physical, emotional and cognitive experience, examining whether there may be an emotional cause for a person's physical pain, and then addressing both issues. In some cases, emotions are used as the key to ease a physical problem; in others the process works the other way.

In one case, Fisher said, a woman came to her who suffered severe chronic back pain and had a history of physical and sexual abuse as a child. Fisher said she worked with the woman's pain as a symptom of her childhood trauma, the way flashbacks or nightmares might be.

"I suggested that her back might be holding hypervigilant, suggested that her back was standing guard for her," she said. "We talked about her back standing guard for her, and as we talked about it, her back started to relax."

Six months after that one session, the only problem the woman has had is occasional achiness, Fisher said, and that when her back starts to get a little tense, she is able to work through it.

"Most situations don't resolve that dramatically," Fisher said.

In another case, a woman came to her who said she had not slept through the night in 25 years since she was sexually assaulted in her home. Even though the rapist was found, arrested, convicted and was still in jail, the woman still felt so scared every night, she could not sleep in the same room with her husband, because the sounds of him rolling over would terrify her.

"Every night she was reliving the experience of being woken up, being terrified and having to be hypervigilant," Fisher said.

They worked together over a period of several months, and when the anniversary of the assault came, they made an appointment for a session.

At that meeting Fisher worked with the woman to reactivate the fight response to what she experienced 25 years before, and to have her feel it in her muscles.

"She pushed against my outstretched arms, very slowly, very slowly because we want people to feel the power of that musculature," Fisher said. "We spent about 20 minutes engaging all the muscles from her feet planted on the ground, through her legs, up through her back and her arms."

Afterwards, the woman felt tired, but did not feel terrified, she said.

"She went home, was able to sleep for a few hours, and was able to feel triumphant over her memory, if not over her assailant," Fisher said.

The approaches to pain treatment being developed by study of the link between emotions and pain offer the hope that drugs will not be the only recourse doctors have when faced with patients who suffer from chronic pain.

"It changes the paradigm, definitely, and opens up new arenas for study," Zautra said. "Pain is a signal, part of the response of the brain and the mind. It is part of a broader class of responses that a person needs to address, and they can use a variety of methods to address it."