Scientists have identified the brain regions responsible for tinnitus, a major step forward in research into the disease.

Ten to fifteen percent of people suffer from chronic tinnitus. Unlike the occasional ringing in the ears most people experience, this is the permanent problem that never goes away and gets worse as one gets older.

More, from Fox News:

This is a 3-D image of the left brain hemisphere of a patient with tinnitus (right) and the part of that hemisphere containing primary auditory cortex (left). Black dots indicate all the sites recorded from. Colored circles indicate electrodes at which the strength of ongoing brain activity correlated with the current strength of tinnitus perceived by the patient. Different colors indicate different frequencies of brain activity (blue = low, magenta = middle, orange = high) whose strength changed alongside tinnitus. Green squares indicate sites where the interaction between these different frequencies changed alongside changes in tinnitus. (Image: Sedley, W et al.)
This is a 3-D image of the left brain hemisphere of a patient with tinnitus (right) and the part of that hemisphere containing primary auditory cortex (left). Black dots indicate all the sites recorded from. Colored circles indicate electrodes at which the strength of ongoing brain activity correlated with the current strength of tinnitus perceived by the patient. Different colors indicate different frequencies of brain activity (blue = low, magenta = middle, orange = high) whose strength changed alongside tinnitus. Green squares indicate sites where the interaction between these different frequencies changed alongside changes in tinnitus. (Image: Sedley, W et al.)

[…] To study the subject’s tinnitus-linked brain activity, researchers tried to temporarily suppress the chronic sound by playing a loud noise for 30 seconds. After turning off the external noise, tinnitus can get quieter or go away for a brief period of time. Researchers then looked at brain scans of when the subject’s tinnitus went away and compared them to times when he experienced no change.

Researchers said they were fortunate because the same noise seemed to randomly make his tinnitus get quieter half the time, and didn’t for the other half— making the man his own control subject.

“That’s why our experiment was really powerful: because it controls for all those other factors related to tinnitus— attention, fatigue— across different experiment conditions. If [the subject] was tired, he was tired across both conditions,” said Gander, who noted that this characteristic prevented confounding factors from impacting the study results.

By directly recording brain activity, researchers were able to conclude that tinnitus affects a large expanse of the brain— not just the sound areas— including regions related to emotions, memory and mood.

“What we’re hoping is that the details of the brain networks and brain mechanisms we highlight in our paper can be starting points that people could target [for treatment],” Gander said.