In the advance online edition of Nature on January 12, 2011, the researchers reported that the number of neurons tuned to the high frequency had jumped by 79% compared to control rats. The scientist then tested 2 different tones in a second group of rats but stimulated the vagus nerve only for the higher one. The neurons tuned to the higher tone increased by 70%, while those tuned to the lower one decreased in number. This showed that the tone alone wasn’t enough to initiate the change; it had to be accompanied by VNS.


Tinnitus affects males and females in equal numbers. It can affect individuals of any age, even children. Tinnitus, collectively, is a very common condition and estimated to affect approximately 10% of the general population. Rhythmic tinnitus occurs far less frequently than non-rhythmic tinnitus, accounting for approximately 1% of all cases of tinnitus and is considered relatively rare in the general population. The exact prevalence or incidence of rhythmic tinnitus is unknown. Rhythmic tinnitus due to pseudotumor and sinus wall anomalies is found most commonly in overweight women in their 3rd to 6th decade of life. The onset of tinnitus can be abrupt or develop slowly over time.
Tinnitus is the hearing of sound when no external sound is present.[1] While often described as a ringing, it may also sound like a clicking, hiss or roaring.[2] Rarely, unclear voices or music are heard.[3] The sound may be soft or loud, low pitched or high pitched and appear to be coming from one ear or both.[2] Most of the time, it comes on gradually.[3] In some people, the sound causes depression or anxiety and can interfere with concentration.[2]

Her most recent study, published in January 2018 in the journal Science Translational Medicine, showed success rates similar to Kilgard’s on 20 adult tinnitus patients. (5) People who underwent the therapy 30 minutes a day for one month reported about a 50 percent drop in the loudness of their tinnitus. More than half of the study participants also reported that their tinnitus bothered them less after the therapy, she says.
Persistent tinnitus may cause anxiety and depression.[14][15] Tinnitus annoyance is more strongly associated with psychological condition than loudness or frequency range.[16][17] Psychological problems such as depression, anxiety, sleep disturbances and concentration difficulties are common in those with strongly annoying tinnitus.[18][19] 45% of people with tinnitus have an anxiety disorder at some time in their life.[20]
According to ATA, The American Tinnitus Association, 45 million Americans are struggling with tinnitus. In Germany the “Deutsche Tinnitus-Liga” estimates that 19 million Germans have experienced tinnitus, and that 2,7 million Germans have persistent tinnitus, of which 1 million have very severe tinnitus. The British Tinnitus Association estimates that 10% of the UK population suffers from tinnitus.  Read more about the prevalence of tinnitus.

It’s the same mechanism that’s happening in people who feel a phantom limb sensation after losing a limb, explains Susan Shore, PhD, a professor of otolaryngology, molecular physiology, and biomedical engineering at the University of Michigan in Ann Arbor. With tinnitus the loss of hearing causes specific brain neurons to increase their activity as a way of compensating, she explains. “These neurons also synchronize their activity as they would if there were a sound there, but there is no external sound,” she adds.


Avoid a too-quiet bedroom. People with tinnitus may find it easier to sleep in a less quiet bedroom, and may benefit from white noise or other sleep-friendly sounds that help mask and minimize their tinnitus. To my patients who are looking to introduce soothing sounds to their sleep environment, I recommend the iHome Zenergy Sleep System, which combines relaxing sounds with aromatherapy and sleep-promoting light therapy.
A loud work environment. A loud work environment that involves the use of power tools, power saws, drills or other noisy equipment may cause temporary bouts of tinnitus. I know of many tinnitus suffers who have attended rock concerts and left with ringing in their ears that may take hours or even days to subside. The longer a person remains in that loud environment, the better their chances will be of developing the condition permanently. These environments can also cause hearing loss. Always wear earplugs when you are in a loud environment, even if it is only going to be for a short time. Mowing the lawn? Wear earplugs.
Most of the causes of tinnitus alter neurological activity within the auditory cortex, the portion of the brain responsible for hearing. The transmission of sound is interrupted, so some of the neural circuits fail to receive signals. Instead of causing hearing loss, as you might expect due to the lack of stimulation, the neural circuits begin chattering. First, they chatter alone. Then, they become hyperactive and synchronous. When we experience this deviation, our brains attempt to compensate for the change by interpreting the neurological activity as sound. This can resemble ringing, buzzing, hissing, whistling, or roaring, amongst a variety of other noises.
If your mind is occupied with something absorbing, it is easier to forget about the tinnitus. Work, leisure pursuits and other interests can all help to provide a worthwhile focus. If you don't have a hobby, now might be the time to start something, many people say that painting or writing helps. Bear in mind however, that excessive activity may produce stress, so take time for relaxing activities and social interaction where possible.
Tinnitus – a sound in the head with no external source – is not a disease; it is a symptom that can be triggered by a variety of different health conditions. So what causes tinnitus? Common sources include hearing loss, ear wax buildup, ototoxic medications, and ear bone changes. No matter what the cause, the condition interrupts the transmission of sound from the ear to the brain. Some part of the hearing system is involved as well, whether the outer, middle, or inner ear.
The diagnosis of tinnitus is usually based on the person's description.[3] A number of questionnaires exist that may help to assess how much tinnitus is interfering with a person's life.[3] The diagnosis is commonly supported by an audiogram and a neurological examination.[1][3] If certain problems are found, medical imaging, such as with MRI, may be performed.[3] Other tests are suitable when tinnitus occurs with the same rhythm as the heartbeat.[3] Rarely, the sound may be heard by someone else using a stethoscope, in which case it is known as objective tinnitus.[3] Spontaneous otoacoustic emissions, which are sounds produced normally by the inner ear, may also occasionally result in tinnitus.[6]
The accepted definition of chronic tinnitus, as compared to normal ear noise experience, is five minutes of ear noise occurring at least twice a week.[50] However, people with chronic tinnitus often experience the noise more frequently than this and can experience it continuously or regularly, such as during the night when there is less environmental noise to mask the sound.
If you develop tinnitus, it's important to see your clinician. She or he will take a medical history, give you a physical examination, and do a series of tests to try to find the source of the problem. She or he will also ask you to describe the noise you're hearing (including its pitch and sound quality, and whether it's constant or periodic, steady or pulsatile) and the times and places in which you hear it. Your clinician will review your medical history, your current and past exposure to noise, and any medications or supplements you're taking. Tinnitus can be a side effect of many medications, especially when taken at higher doses (see "Some drugs that can cause or worsen tinnitus").
Loud noise exposure: Being exposed to occupational loud noise on a regular basis from heavy equipment, chain saws or firearms is a common cause of tinnitus. However, even if you don’t work in a noisy environment, you can still suffer the effects of noise exposure by listening to loud music through headphones, attending live music performances frequently and engaging in noisy hobbies.
×