Not everyone who has a hearing loss will suffer from tinnitus, but it is common for those who have tinnitus to also have a hearing loss. Research is helping us understand why tinnitus happens, but how are the two conditions linked?
How And What
First, let’s look at the basics of how hearing works.
- An external sound makes sound waves. These travel into the outer ear, made up of the ear canal and eardrum. Sound travels down the ear canal, and strikes the eardrum.
- The sound striking the eardrum causes it to vibrate. These vibrations travel on towards the middle ear, made up of 3 tiny bones, known as the ossicles (malleus, incus and stapes). The vibrations from the eardrum will result in the ossicles vibrating.
- Vibrations move the fluid of the inner ear (cochlear), and cause the tiny hair cells inside to move.
- Movements convert into electrical signals to send to the auditory nerves. Nerves then transmit electrical impulses to the brain – which are interpreted as sound.
If any part of this delicate system is damaged or blocked, it can reduce or prevent sound signals to the brain. This can lead to increased activity in the form of spontaneous signals to the hearing center of the brain (basically the brain trying to fill in the gaps). This causes sounds to be perceived, even though no sound signals were received from an external source. This is what tinnitus is.
If you have a hearing loss, you are also likely to be more aware of your tinnitus because there is less environmental sound to block out the phantom sounds.
Causes And Links
There can be many potential causes of tinnitus. Most common is damage of varying degree to the inner ear, as commonly found in sensorineural hearing loss. This can be caused through loud noise exposure, ageing or Meniere’s disease.
Loud noise exposure in particular is known to damage the nerves and tiny hairs of the inner ear, directly affecting signals travelling to the brain.
Tinnitus is linked to blockages in the outer or middle ear known as conductive hearing loss. Here sound waves are prevented from reaching the inner ear. Examples of this could be ear wax build up, ear infections, a benign tumor on a hearing nerve or an abnormal bone growth called otosclerosis.
Tinnitus can also be linked to some medications such as aspirin, ototoxic drugs, cancer drugs and more. It can also be caused by a perforated eardrum, head trauma or stress. Unfortunately stress and anxiety often increase as tinnitus continues, creating a cycle of symptoms.
Tinnitus can be temporary or long term, it can be severe or mild. If you experience tinnitus symptoms, we recommend booking in a hearing assessment. Our hearing care professionals can help relieve the symptoms of tinnitus. Call us to book in today on 888-342-4734, or click here to request an appointment.