The root of tinnitus, explained by scientists

Between 5 and 15 percent of people say they have heard a type of phantom noise sometime during the last six months. Tinnitus is an extremely common condition. It affects up to 1 in 10 adults in those over 60. Although often referred to as “ringing in the ears”, it can be perceived as many different sounds, including hissing, clicking or whistling.

 A condition that followed men through centuries… and no real solution yet!

Some of the world’s oldest medical texts, including Antic Egyptian papyrus scrolls and clay tablets from Assyria, mention tinnitus as a common experience and describe it as “buzzing” , “whispering” or “singing”.

If early physicians treated it as what they believed this condition to be, now we have modern alternatives for an ailment that is actually “untreatable” in all major medicine compendiums.

In the past, some were sure tinnitus is caused by wind trapped in the ear, that swirled around… and tried to liberate it by drilling a hole into the bones of the ear. Today’s most popular medical alternatives include drugs, but also alternative therapies, such as alleviant sounds. Some doctors prescribe lidocaine. One thing is sure: there is no certain medically homologated solution that would offer a full relief.

And here’s why!

Recent studies suggest it has to do with the root cause of tinnitus, which has nothing to do with your ears, but with your brain.

When we hear sounds, our eardrums vibrate. The vibration makes the nerve hairs in the inner ear to shiver and thus to create an electric signal that travels along the auditory nerve into the brain. Each nerve hair is tuned to a specific frequency of sound and that is why it can only excite certain neurons in the auditory cortex. The neurons in the auditory cortex, which is actually a patch of gray matter, form a tone map. While the neurons at one end of the auditory cortex are toned to low frequencies, the farther you go toward the other end, the higher the tuning is.

Neurons are more than sending signals to the brain. They are also reaching to neighboring neurons, tuned to nearby frequencies to adapt so that we don’t become overwhelmed by meaningless noise. This type of feedback mechanism creates a complex, flexible network.

The root cause? Deep inside the brain.

Tinnitus comes in when the flexibility of the network goes bad. Whether is because of drugs, loud noises, injuries or simply unexplained, if hair nerves can’t send signals from the ear to the tone map, the neurons start to eavesdrop on their neighboring ones, firing unpleasant and disturbing frequencies. Sometimes, neurons even end up in self-sustaining loop, producing a constant ringing, which doesn’t go away not even when people get their auditory nerve surgically cut.

According to Winfried Schlee of the University of Konstanz in Germany, every time the neurons send each other signals, their electric current creates a magnetic field; studying this magnetic filed, Schlee and his colleagues were surprised to find out that tinnitus patients have a more synchronized patter of signals coming out of the front and the back of the brain, than non-sufferers. This means that tinnitus extends way beyond the ear or any hearing specialized part of the brain, being a disease of networks that span the brain.

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