Partial or total deficit of hearing in either ear. Of assistance are hearing aids, lip-reading, a cochlear implant in the ear in combination with a special electronic processor, sign language, and “cued speech” (manual clarification of ambiguous lip movement during speech).
Conductive deafness is due to faulty conduction of sound inward from the external ear, usually due to infection (see otitis), or a hereditary abnormality of the bones of the inner ear (see otosclerosis).
Perceptive deafness may be inborn or caused by injury or disease of the cochlea, auditory nerve, or the hearing centers in the brain. It becomes more common with age.
Partial or complete loss of hearing.