Sensorineural hearing loss is a condition in which sound reaches the inner ear but a person is unable to process it properly. This type of hearing loss occurs because of a problem in the inner ear, the cochlear (auditory) nerve, or, rarely, a problem within the brain.
The most common cause of sensorineural hearing loss is damage to the tiny hair cells of the inner ear. This damage can occur with age or from repeated exposure to loud noise. Nerve damage may also cause this type of hearing loss. Nerves that relay sound impulses can become damaged as a result of disease (such as multiple sclerosis), having a stroke, or from a tumor.
Sensorineural hearing loss can occur suddenly or gradually and often cannot be reversed.
WebMD Medical Reference from Healthwise