Hyperactivity and deep brain stimulation. Researchers have observed hyperactivity in neural networks after exposing the ear to intense noise. Understanding specifically where in the brain this hyperactivity begins and how it spreads to other areas could lead to treatments that use deep brain stimulation to calm the neural networks and reduce tinnitus.
Tinnitus (pronounced ti-nə-təs or tə-nī-təs) is the conscious awareness of a sound in your ears or head not caused by an external noise. Too often associated with hearing loss, the fact is more than 50 percent of people living with tinnitus don’t have measurable hearing loss. Since there are many causes, tinnitus can be associated with a variety of health problems.
Somatic tinnitus is caused, worsened, or otherwise related to your body’s own sensory system. Sensory signals coming from various parts of the body are disrupted, causing a spasm that produces tinnitus. Those who have somatic tinnitus usually have it in only one ear. Depending on the root cause your doctor may come up with treatment options to alleviate the symptoms.
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.
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.
Approximately 50 million Americans have some form of tinnitus. For most people, the sensation usually lasts only a few minutes at a time. About 12 million people have constant or recurring tinnitus that interferes with their daily life so much that they seek professional treatment. For these individuals, tinnitus may result in a loss of sleep, interfere with concentration, and create negative emotional reactions such as despair, frustration, and depression.
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.
Tinnitus usually comes in the form of a high-pitched tone in one or both ears, but can also sound like a clicking, roaring or whooshing sound. While tinnitus isn't fully understood, it is known to be a sign that something is wrong in the auditory system: the ear, the auditory nerve that connects the inner ear to the brain, or the parts of the brain that process sound. Something as simple as a piece of earwax blocking the ear canal can cause tinnitus, but it can also arise from a number of health conditions. For example, when sensory cells in the inner ear are damaged from loud noise, the resulting hearing loss changes some of the signals in the brain to cause tinnitus.
Smoking. Contrary to popular belief, there are some external irritants that can cause tinnitus. For example, Nicotine has been proven to be an irritant that can cause someone to develop a ringing in their ears. Smokers may find that their chances of developing the condition may be higher than someone who is a non-smoker. If you’re suffering from tinnitus right now, and you’re a smoker, please quit as soon as possible. If that’s just not an option for you right now, be sure to at least pick up an over the counter tinnitus treatment that will dramatically reduce the ringing in your ears.
Subjective tinnitus is the most common type and accounts for 95 percent of cases. Only you can hear it and it’s usually caused by exposure to excessive noise. It can appear suddenly and may last three months (acute) to 12 months (subacute), or longer. Subjective tinnitus is often accompanied by hearing loss due to hair cell nerve damage. The severity of symptoms varies from patient to patient, and largely depends on your reaction to the noise.
Until recently, most tinnitus patients had little reason to believe doctors would ever be able to completely cure or reverse the affliction. Drug therapies had consistently failed, and so had more invasive procedures — including some surgeries to remove the auditory nerve that transmits sound from the ear to the brain, according to past research. (1,2)
Can an iPhone app truly relieve tinnitus? Believe it or not, the answer is yes. The ReSound LiNX2 app utilizes a combination of sound therapy and relaxation exercises to reduce the severity of tinnitus. The convenient app can be used in combination with hearing instruments, which are small but strong. This groundbreaking program transforms your iPhone into a remote control for your hearing aid.
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Although mitochondrial DNA variants are thought to predispose to hearing loss, a study of polish individuals by Lechowicz et al, reported that "there are no statistically significant differences in the prevalence of tinnitus and its characteristic features between HL patients with known HL mtDNA variants and the general Polish population." This would argue against mitochondrial DNA variants as a cause of tinnitus, but the situation might be different in other ethnic groups.
There's no known cure for tinnitus. Current treatments generally involve masking the sound or learning to ignore it. A research team led by Dr. Michael Kilgard at the University of Texas at Dallas and Dr. Navzer Engineer at MicroTransponder, Inc. set out to see if they could develop a way to reverse tinnitus by essentially resetting the brain's auditory system. Their work was funded in part by NIH’s National Institute on Deafness and Other Communication Disorders (NIDCD).
It’s been found that exposure to very loud noises can contribute to early hearing loss and ear problems. Loud sounds can include those from heavy machinery or construction equipment (such as sledge hammers, chain saws and firearms). Even gun shots, car accidents, or very loud concerts and events can trigger acute tinnitus, although this should go away within a couple days in some cases. (5)
Exposure to loud noise. Loud noises, such as those from heavy equipment, chain saws and firearms, are common sources of noise-related hearing loss. Portable music devices, such as MP3 players or iPods, also can cause noise-related hearing loss if played loudly for long periods. Tinnitus caused by short-term exposure, such as attending a loud concert, usually goes away; both short- and long-term exposure to loud sound can cause permanent damage.