While there may be a wide range of causes, an important underlying factor for the development of tinnitus is brain plasticity.5,7 This property allows the brain to change and adapt, and it is essential to how we learn. Unfortunately, in some cases, such as with hearing loss, the auditory part of the brain may be altered as brain plasticity tries to compensate for the abnormal auditory inputs. This response leads to changes in brain activity in the auditory system (e.g., the auditory cortex) that can create a phantom percept: tinnitus. As such, while tinnitus may begin a problem at the auditory periphery, it persists because of changes throughout the auditory system. Treating tinnitus may require addressing both the initiator (e.g., hearing loss) and the driver (changes in the auditory brain).
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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.”
Hearing loss: Probably the most common cause for tinnitus is hearing loss. As we age, or because of trauma to the ear (through noise, drugs, or chemicals), the portion of the ear that allows us to hear, the cochlea, becomes damaged. Current theories suggest that because the cochlea is no longer sending the normal signals to the brain, the brain becomes confused and essentially develops its own noise to make up for the lack of normal sound signals. This then is interpreted as a sound, tinnitus. This tinnitus can be made worse by anything that makes our hearing worse, such as ear infections or excess wax in the ear.
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.
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.
Steven Doerr, MD, is a U.S. board-certified Emergency Medicine Physician. Dr. Doerr received his undergraduate degree in Spanish from the University of Colorado at Boulder. He graduated with his Medical Degree from the University Of Colorado Health Sciences Center in Denver, Colorado in 1998 and completed his residency training in Emergency Medicine from Denver Health Medical Center in Denver, Colorado in 2002, where he also served as Chief Resident.
Between 2007 and 2011, the researchers recruited 492 Dutch adults who had been diagnosed with tinnitus. The patients had to fulfil several criteria, including having no underlying disease that was causing their tinnitus, no other health issues that precluded their participation, and to have received no treatment for their tinnitus in the five previous years. Some 66% of adults originally screened for the study participated after screening.
Participants were contacted to complete questionnaires (including THI) for the three-month assessment. A 30-minute individual phone interview with each participant was also conducted to explore their experiences with using the music package on a daily basis, and to further understand how the music package was affecting their tinnitus. At present, 27 participants have been interviewed to obtain the results presented here.
Though the exact cause of tinnitus — as in the specific mechanism that creates these phantom sounds in some people — remains unknown, contributing factors and triggers have been identified. Excessive exposure to loud noise is often a factor because of the damage done to your auditory system. Tinnitus may also result from jaw-joint dysfunction (e.g., teeth grinding, temporomandibular joint disorder) or chronic neck muscle strain.
Experts recommend that patients with severe tinnitus become educated about tinnitus and how they best deal with its symptoms. This can include learning about biofeedback in order to control stress and your reaction to tinnitus sounds, talking with a counselor, or joining a support group. Coping strategies are most useful for managing emotional side effects of tinnitus, such as anxiety, trouble sleeping, lack of focus and depression.
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.
As an initial test of our treatment, we first conducted a small pilot study to see if there were measurable benefits within 3 to 6 months of using this therapy. While we did not inform participants of whether they would receive a treatment or unaltered music, every participant in fact received a treatment. Participants reported a drop in scores on the Tinnitus Handicap Inventory (THI) within 3 months of using their personalized sound therapy for about 2 hours a day. THI is a psychometrically robust and validated questionnaire that assesses the impact of tinnitus on daily living and the degree of distress suffered by the tinnitus patient. Furthermore, we saw increased benefits after 6 months of treatment use (Figure 1). This data suggested that our treatment may be engaging brain plasticity in a positive manner, thereby gradually reducing tinnitus over time. Armed with this information, we designed a more rigorous trial that is very uncommon among research in tinnitus therapies.
Tinnitus is commonly thought of as a symptom of adulthood, and is often overlooked in children. Children with hearing loss have a high incidence of tinnitus, even though they do not express the condition or its effect on their lives. Children do not generally report tinnitus spontaneously and their complaints may not be taken seriously. Among those children who do complain of tinnitus, there is an increased likelihood of associated otological or neurological pathology such as migraine, juvenile Meniere’s disease or chronic suppurative otitis media. Its reported prevalence varies from 12% to 36% in children with normal hearing thresholds and up to 66% in children with a hearing loss and approximately 3–10% of children have been reported to be troubled by tinnitus.
We encourage you to avoid anything that can make your tinnitus worse. For instance, you may want to avoid smoking, drinking alcohol, or listening to loud noises. Another precaution is protection. If you’re a construction worker, airport worker, hunter, or regularly exposed to loud noise, you should wear custom earplugs or special earmuffs. Ear protection goes a long way towards preventing your tinnitus from getting worse.
Hearing (audiological) exam. As part of the test, you'll sit in a soundproof room wearing earphones through which will be played specific sounds into one ear at a time. You'll indicate when you can hear the sound, and your results are compared with results considered normal for your age. This can help rule out or identify possible causes of tinnitus.
The researchers paired electrical stimulation of the vagus nerve — a large nerve that runs from the head to the abdomen — with the playing of a tone. Vagus nerve stimulation (VNS) is known to release chemicals that encourage changes in the brain. This technique, the scientists reasoned, might induce brain cells (neurons) to tune to frequencies other than the tinnitus one. For 20 days, 300 times a day, they played a high-pitched tone to 8 rats during VNS.
In many cases, tinnitus is caused by hyperactivity (or too much activity) in the brain’s auditory cortex. “When there’s damage or a loss of input in the ear [such as hearing loss, head trauma, or a blood vessel problem], the brain tries to turn up certain channels in order to compensate,” Dr. Kilgard explains. When the brain doesn’t get that tuning quite right, the result is tinnitus.
Tinnitus is associated with a high level of emotional stress. Depression, anxiety, and insomnia are not uncommon in people with tinnitus. Cognitive behavioral therapy (CBT) is a type of talk therapy that helps people with tinnitus learn to live with their condition. Rather than reducing the sound itself, CBT teaches you how to accept it. The goal is to improve your quality of life and prevent tinnitus from driving you crazy.
Cochlear Implants. These implants are a treatment option for patients that have a severe hearing loss along with tinnitus. Cochlear implants are designed to bypass any damaged parts of the inner ear and send the electrical signals sound makes directly to the auditory nerve. By bringing in outside noise, these implants can effectively mask your tinnitus, as well as stimulate your neural circuits to change.
Tinnitus is commonly accompanied by hearing loss, and roughly 90% of persons with chronic tinnitus have some form of hearing loss (Davis and Rafaie, 2000; Lockwood et al, 2002). On the other hand, only about 30-40% of persons with hearing loss develop tinnitus. According to Park and Moon (2004), hearing impairment roughly doubles the odds of having tinnitus, and triples the odds of having annoying tinnitus.
Prevention involves avoiding loud noise. If there is an underlying cause, treating it may lead to improvements. Otherwise, typically, management involves talk therapy. Sound generators or hearing aids may help some. As of 2013, there were no effective medications. It is common, affecting about 10–15% of people. Most, however, tolerate it well, and it is a significant problem in only 1–2% of people. The word tinnitus is from the Latin tinnīre which means "to ring".
To keep the brain activated and aware, Kilgard’s therapy involves stimulating the vagus nerve, which is actually a pair of nerves that runs inside the neck and into the brain. “All the stuff you brains learns about your body — it all comes in through the vagus nerve,” he says. “We trick the brain into thinking it’s learning something important by stimulating this nerve in the neck.”
Many drugs have been studied for treating tinnitus. For some, treatment with low doses of anti-anxiety drugs -- such as Valium or antidepressants such as Elavil -- help reduce tinnitus. The use of a steroid placed into the middle ear along with an anti-anxiety medicine called alprazolam has been shown to be effective for some people. Some small studies have shown that a hormone called misoprostol may be helpful in some cases.