Deafness Results from an Interruption in the Hearing Process

Clinical deafness may result from a loss of sound transmission in the outer or middle ear, called conduction deafness, or from malfunction of the cochlear hair cells or eighth nerve fibers, called nerve deafness. Given that auditory information from one ear is significantly distributed to both sides of the central nervous system, unilateral damage to the auditory system in the brain is often difficult to detect or to localize with a tra­ditional hearing test. In veterinary medicine, deafness in young animals is usually caused by a congenital defect in the cochlea, frequently associated with white coat coloration. Certain antibiotics, diuretics, and anti neoplastic agents have ototoxic properties capable of damaging cochlear structures.