The problem of ear ringing, also known as tinnitus, may appear a minor health problem, but unremitting ringing in the ears can prove to be much more than a nuisance, infuriating and even debilitating.
In order to solve the longstanding health mystery of tinnitus, the researchers at the University of Iowa used a specialized invasive brain monitoring technology for observing and locating the networks of brain that are responsible for phantom ear ringing in real time.
Will Sedley, a study co-author from Newcastle University in England, said, “Perhaps the most significant exposure was that activity directly associated with tinnitus was very extensive and spanned a large proportion of the part of the brain we measured from. In contrast, the brain responses to a sound we played that mimicked the subject’s tinnitus were localized to just a tiny area.”
The technique for monitoring is used during epilepsy surgery, but the technology is important for the purpose of tracking the neurological origins of tinnitus, the cause of which is usually unknown.
Phillip Gander, study author and PhD scholar in neurosurgery department at Iowa, said, “This has profound implications for the better understanding and treatment of ear ringing. This may not be treatable by only targeting at a localized part of the hearing system.”
In order to locate tinnitus’ source, the study researchers compared the signals of brain during stronger and weaker moments of ringing. The researchers also monitored the signals of brain while the patients were listening to a real ring mimicking the phantom sound.
The researchers found that the actual sounds produced brain activity in a specifically contained and localized manner. On the other hand, the phantom ringing produced a massive network of brain stimulation in the patient.
Explaining the findings, Gander said, “The sheer amount of the brain across which the tinnitus network is present suggests that tinnitus may not simply ‘fill in the gap’ left by hearing damage, but also actively infiltrates beyond this into wider brain systems.”
The findings of the study were published in the journal Current Biology.