When undergoing some mind-over-matter alternative treatments for pain, patients are often told to visualize their pain as a fiery mass to be cooled, a sharp knife to be withdrawn, a red ball to be thrown away from one's self, or a fish to be snatched up by a shark. In a recent Stanford University School of Medicine study, patients got to visualize their pain as blood flow to select areas of their brains.
And, by observing their brain activity in real time, patients were able to manage their suffering. The study, published in the December 12th online edition of the Proceedings of the National Academy of Sciences, makes strides in understanding the connection between the brain and the mind.
Advertisement
"I think it nicely extends upon what we've known for some time: that there's a direct mind-body interaction, that ultimately our perception of pain resides in our brain," said study coauthor Sean Mackey. "What we're now doing is bringing a real neurophysiologic understanding to how we control our brain activity and where in the brain that is being controlled. We hope in the future we can use this information to target specific therapies to those brain regions."
Mackey and his team used fMRI to scan the brains of two groups of subjects: eight chronic pain patients and 36 healthy people who received pain via a non-harmful heat stimulus to the palm. Using state-of-the-art software, the team was able to analyze the fMRI images at the exact moments when the subjects experienced pain.
The researchers located the area of each subject's brain that responded to pain, and then allowed the subject to observe activity in that area as it occurred. Each participant was asked to "cognitively modulate" the brain signal.
"We would have them think about turning the brain activation up and down," Mackey said. "And it's not just a simple thing of being in a scanner and saying, 'Well, I want it to go up,' and it goes up, or, 'I want it to go down,' and it goes down. You actually have to engage certain brain processes to be able to move that signal up and down."
The researchers gave the patients a few possible strategies for signal modulation, such as focusing first on the pain and then away from the pain or changing the perception of the sensation from unbearably hot to soothingly warm.
Over the course of three sessions, the patients overwhelmingly learned how to successfully modulate the signal and manage both the intensity and unpleasantness of their pain.
So, how did they do it? The researchers aren't sure.
"The challenge in this is that most people had a real difficult time describing what they were finally doing," Mackey said. "We don't really have a vernacular, a way of describing how we control our brains. When you reach out to grab a pencil, you couldn't really describe how you reached out to grab that pencil."
Mackey said he and his team are currently trying to figure out what techniques work by asking patients to concentrate on specific strategies and observing their success. They are also examining the differences between more and less successful individuals and conducting a larger trial with chronic pain patients to see the long-term effectiveness of these methods on pain control.
While this technique will not be available to the public any time soon, Mackey believes the research might have more immediate implications for understanding how existing psychological techniques for controlling pain work, and how to better utilize these strategies.