A Northwestern Medicine study, the first longitudinal brain imaging study to track participants with a new back injury, showed how chronic pain may be caused as a result of an emotional response to an injury.
As Sky News reports, the process occurs due to interaction between two brain regions, the frontal cortex and nucleus accumbens, related to emotional and motivational behavior. The more they communicate, the more likely pain will persist after the injury has healed.
Professor Vania Apakarian, from Northwestern University in Chicago, who lead the study explained: “The injury itself is not enough to explain the ongoing pain. It has to do with the injury combined with the state of the brain.”
The results showed that the more emotionally the brain reacts to the initial injury, the chance a patient will develop chronic pain.
Prof Apakarian continued: “It may be that these sections of the brain are more excited to begin with in certain individuals, or there may be genetic and environmental influences that predispose these brain regions to interact at an excitable level.”
The results, published in the journal Nature Neuroscience, may also provide scientists with a new direction for developing therapies to treat intractable pain.
According to a 2011 National Academy of Science report, chronic pain affects about 40 million adults in the United States.
“For the first time we can explain why people who may have the exact same initial pain either go on to recover or develop chronic pain,” Prof Apakarian said. “Now we hope to develop new therapies for treatment based on this finding.”
The conducted study made it possible to predict with 85 per cent accuracy which individuals would go on to develop chronic pain.
By the way, there’s one more study which suggests that mental distractions may make pain easier to handle, writes American News Report.
The scientists of University Medical Center Hamburg-Eppendorf have found that mental distractions inhibit responses to the earliest stage of pain signals and may affects endogenous opioids, which are responsible for the relief of pain.
“The results demonstrate that this phenomenon is not just a psychological phenomenon, but an active neuronal mechanism reducing the amount of pain signals ascending from the spinal cord to higher-order brain regions,” said lead researcher Christian Sprenger.
The participants of the study were asked to work on easy and hard memory tasks, while also being subject to painful heat to their arms. The results showed that people perceive less pain when distracted by the harder memory tasks.
A second study confirmed that past experience with needle pricks, along with information received before an injection, shape your pain experience.
“Throughout our lives, we repeatedly experience that needles cause pain when pricking our skin, but situational expectations, like information given by the clinician prior to an injection, may also influence how viewing needle pricks affects pain,” explained lead author Marion Höfle, a doctoral student at the Charité – Universitätsmediz in Berlin.
“Clinicians may be advised to provide information that reduces a patient’s expectation about the strength of forthcoming pain prior to an injection,” Höfle continued.
She stated that, “because viewing a needle prick leads to enhanced pain perception as well as to enhanced autonomic nervous system activity, we’ve provided empirical evidence in favor of the common advice not to look at the needle prick when receiving an injection.”