Hearing loss is the result of sound signals not reaching the brain. There are two main types of hearing loss, depending on where the problem lies. 1  Sensorineural hearing loss is caused by damage to the sensitive hair cells inside the inner ear or damage to the auditory nerve.earing loss is the result of sound signals not reaching the brain. There are two main types of hearing loss, depending on where the problem lies. 1  Sensorineural hearing loss is caused by damage to the sensitive hair cells inside the inner ear or damage to the auditory nerve.