Sensorineural Hearing Loss
The term sensorineural hearing loss means hearing loss originating in the sensory organ (the cochlea) or the auditory nerve. This occurs when the hair cells in the cochlea fail to generate electrical signals in response to sound, or the auditory nerve fails to receive and transmit these electrical signals.
Symptoms may include:
- People appear to mumble (their speech is not clear)
- Difficulty following conversation in noisy environments
- Sound perceived at a lower volume
- Ringing in the ears (tinnitus)
It is the most common type of hearing loss and becomes increasingly common with increasing age. As our ears age, the hair cells inside the cochlea begin to breakdown due to years and years of exposure to noise. The hair cells that detect high-frequency sounds, being positioned at the start of the cochlea and thus exposed to a greater number of sounds, tend to degrade first. For this reason, high-frequency sensorineural hearing loss is increasingly common with increasing age.
Sensorineural hearing loss may also be caused by exposure to excessively loud noises. Loud noises (above 85 decibels) have the potential to damage the hair cells in the cochlea through the force of their vibrations. Over time and through repeat exposure these loud noises cause permanent damage to the hair cells resulting in permanent hearing loss. Symptoms may include ringing in the ears (tinnitus), dullness of hearing, and difficulty hearing in noisy environments (cafes, restaurants etc). Power tools, amplified music, and firearms are three common causes of noise induced hearing loss.
There is a wide range of other causes of sensorineural hearing loss. Genetics, certain medical conditions (such as Meniere’s disease), viral infections, and even some medications can all cause sensorineural hearing loss.