Ringing in the ears, otherwise known as tinnitus, is the perception of sound within the ear in the absence of external sound. Tinnitus is very common and affects predominantly people over 55, according to the journal “B-ENT.” Tinnitus is a symptom and not a disease, and arises from a number of very different environmental and genetic factors. There are several potential causal mechanisms that trigger tinnitis.
Nerve Damage
Vibration of thousands of microscopic hairs in a region of the inner ear called the cochlea leads to conversion of auditory information into electrical signals in the nervous system, which are interpreted by the brain as sound. Damage to, or loss of these hairs may change the delicate balance of sound transmission in the ear, leading to a perception of persistent ringing in the ears, according to the journal “Acta Otorrinolaringol Esp.” Nerve damage associated tinnitus is frequently reported by patients who have been exposed to sustained periods of loud noise, and also by people over 55.
Vascular Problems
Perception of noise in the ear sometimes corresponds to the beats of the heart, and this condition is known as vascular tinnitus. Increased turbulence of blood flowing in the ear is thought to cause vascular tinnitus, perhaps due to fatty deposits leading to a narrowing of the arteries, and subsequent increased blood pressure in these vessels, otherwise known as atherosclerosis, according to the website Tinnitus-audiology.
Fluid Buildup
Transmission of sound from the eardrum to the inner ear is facilitated by vibration of three tiny bones known as the hammer, anvil and stirrup. Persistent ear infections frequently lead to build up of fluid and bacteria within the middle ear, which may inhibit the transmission of sound. Patients with this condition often report tinnitus. However, this type of tinnitus is usually experienced by children and rarely continues into adulthood, according to the National Institutes of Health website.
Increased Neural Activity
Increased activity in the auditory brainstem, where sound is processed in the brain has been highlighted as a potential cause of tinnitus in some patients, particularly those with age induced hearing loss, as indicated by a key study published in October 2005 in “Hearing Research.”
Meniere's Disease
Attacks of tinnitus, vertigo, a feeling of pressure in the inner ear and sporadic hearing loss are some of the sympytoms of Meniere’s disease. The genetic, and environmental factors that cause this disorder of the inner ear have not been identified, according to the website Dizziness-and-balance.
References
- The Royal Belgian Society for ENT and Head and Neck Surgery: Prevalence of tinnitus and audiometric shape
- Acta Otorrinolaringol Esp :Physiopathological mechanisms in tinnitus generation and persistence
- Hearing Research: Course of hearing loss and occurrence of tinnitus
- dizziness & Balance.com: Meniere's disease
