Tinnitus can be extremely disturbing to people who have it. In many cases it is not a serious health problem, but rather a nuisance that may go away. However, some people with tinnitus may require medical or surgical treatment. Sixteen million Americans seek medical treatment each year for tinnitus, and about one-quarter of those experience it so severely it interferes with their daily activities.
The diagnosis of tinnitus is usually based on the person's description. A number of questionnaires exist that may help to assess how much tinnitus is interfering with a person's life. The diagnosis is commonly supported by an audiogram and a neurological examination. If certain problems are found, medical imaging, such as with MRI, may be performed. Other tests are suitable when tinnitus occurs with the same rhythm as the heartbeat. Rarely, the sound may be heard by someone else using a stethoscope, in which case it is known as objective tinnitus. Spontaneous otoacoustic emissions, which are sounds produced normally by the inner ear, may also occasionally result in tinnitus.
Age-Related Hearing Loss: Also known as presbycusis, age-related hearing loss results from the cumulative effect of aging on hearing. This permanent, progressive, and sensorineural condition is most pronounced at higher frequencies. It commonly impacts people over the age of 50, as all people begin to lose approximately 0.5% of the inner ear’s hair cells annually starting at age 40.
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.
Schecklmann et al (2014) suggested that tinnitus is associated with alterations in motor cortex excitability, by pooling several studies, and reported that there are differences in intracortical inhibition, intra-cortical facilitation, and cortical silent period. We doubt that this means that motor cortex excitability causes tinnitus, but rather we suspect that these findings reflect features of brain organization that may predispose certain persons to develop tinnitus over someone else.
Demographic variables (age, sex, type of tinnitus) and baseline THI scores of placebo (n = 16) and treatment (n = 11) groups did not significantly differ from one another at the start of the study. At 3 months, participants in the treatment group reported significantly lower scores on the THI when compared to the placebo group (p < .05). The treatment group also showed an 11-point drop in THI scores when comparing baseline and 3 months (p < .05; please see Figure 2). THI scores for the placebo group comparing both time points were non-significant. Past studies have indicated that the minimum change in the THI score to be considered clinically significant is a drop of 6 to 7 points.9 As such, the results of our clinical study suggest that tinnitus and its related symptoms can produce a clinically significant reduction in tinnitus within the first 3 months using the personalized music-based therapy.
Tinnitus also could be the result of neural circuits thrown out of balance when damage in the inner ear changes signaling activity in the auditory cortex, the part of the brain that processes sound. Or it could be the result of abnormal interactions between neural circuits. The neural circuits involved in hearing aren’t solely dedicated to processing sound. They also communicate with other parts of the brain, such as the limbic region, which regulates mood and emotion.
The exact biological process by which hearing loss is associated with tinnitus is still being investigated by researchers. However, we do know that the loss of certain sound frequencies leads to specific changes in how the brain processes sound. In short, as the brain receives less external stimuli around a specific frequency, it begins to adapt and change. Tinnitus may be the brain’s way of filling in the missing sound frequencies it no longer receives from the auditory system.
But it’s still a significant improvement. And Kilgard says he and others are working to make the treatment even more effective. He suspects this type of therapy is not too far off from being available to patients outside of research studies. “It’s in the late stages of development,” he says. “It could be available to the public in as little as a year or two.”
People with warning signs should see a doctor right away. People without warning signs in whom tinnitus recently developed should call their doctor, as should people with pulsatile tinnitus. Most people with tinnitus and no warning signs have had tinnitus for a long time. They can discuss the matter with their doctor and be seen at a mutually convenient time.
Experts believe that tinnitus is associated with neural (brain and nerve) injuries that affect the auditory pathway and therefore someone’s ability to hear sounds. (10) Most of the time, tinnitus is a result of a disorder that affects parts of either the outer, inner or middle ear. The good news is that the majority of cases are not linked to any serious illness, although some cases are.
While there are many different FDA-approved treatments for tinnitus available, the most important component is finding the right partner (i.e. a Doctor of Audiology), who will work closely with you to help explain your tinnitus and treatment progress over time. In order for the options below to be as successful as possible, the proper support and guidance from an experienced tinnitus specialist is mandatory.