Ringing ears and constant pain in your back may not seem like they are correlated, but new research suggests the link might be closer than we initially expected.
In a recent clinical review, both chronic pain and ringing in the ears (tinnitus) are categorized by changes in two regions of the brain. The regions responsible for these conditions – the nucleus accumbens and the ventromedial prefrontal cortex – are both located in the front of the brain. These systems act as stimulus “gatekeepers,” according to researchers, and when systems go awry, ringing ears and chronic pain can set in.
“It’s a very clever system,” said Josef Rauschecker, a professor of physiology and biophysics at Georgetown University and lead author of the review.
Rauschecker likened the flood of signals your brain receives on a regular basis to living near a train track. When you first move in, the noise from the train might drive you crazy, but after a while, your brain unconsciously begins to dismiss the noise. Eventually, it ignores the noise altogether.
But with chronic pain and tinnitus, there’s something wrong with the part of your brain that inherently ignores this background noise.
“If you step back, you can see the similarity [between the two conditions],” Rauschecker said. “In both tinnitus and chronic pain, the body sends signals to the brain that really don’t mean anything, but these signals are not filtered out, as they normally would be.”
Confirmed Through MRI
For their study, researchers examined structural MRI results of patients with chronic pain and tinnitus. Structural MRIs showed that people with those conditions had a smaller ventromedial prefrontal cortex, while a function MRI scan showed that these people exhibited increased activity in the nucleus accumbens.
Both of these regions regulate emotions and executive function, which is categorized as the thinking that control other types of thinking, like planning and then executing a task. When combined, they formulate a central gatekeeping system that allows our bodies to interpret signals and react accordingly. But when they are damaged, the brain can interpret certain signals as chronic pain, tinnitus or another condition.
“It’s an interesting idea based on solid facts, and it opens up the possibility for new treatments and prevention tools,” Rauschecker concluded.