What Are The Three Types Of Hearing Loss?
How does hearing work?
Sound comes from vibrations in the environment. When sounds reach the ear, they travel through the air-filled middle ear space by vibrating the eardrum and, in turn, the small middle ear bones. This vibration reaches the fluid-filled cochlea (inner ear), where the fluid is set into motion by the vibration of the middle ear bones. The motion of the fluid passes the vibration along to a thin membrane that houses auditory receptor cells, known as hair cells. The vibration of the inner ear membrane causes these hair cells to release an electrical charge, changing the mechanical vibration into a nerve impulse. This electrical nerve impulse travels up the auditory nerve to the hearing center of the brain, where it is detected and identified. Hearing loss can occur at any point along this pathway when the transmission of sounds from the environment is either altered or stopped. Listed below are different types of hearing loss and how they occur.
What is conductive hearing loss?
Conductive hearing loss occurs when there is a blockage or breakdown in the auditory stimuli’s ability to get to the inner ear. The blockage can occur from earwax, ear infections (otitis media and otitis externa), middle ear fluid, microtia/atresia, ossicular (or hearing bone) abnormality, or perforation of the eardrum. Conductive hearing loss is often reversible.
What is sensorineural hearing loss?
Sensorineural hearing loss occurs when there is damage to the inner ear (cochlea), or to the nerve pathways from the inner ear to the brain. This damage can occur from genetics or heredity, ototoxic (toxic to the ear) medications, age, illness, head trauma, exposure to loud noises or may have no known cause. Sensorineural hearing loss is typically permanent and may worsen or progress over time.
What is a mixed hearing loss?
A mixed hearing loss is when both a sensorineural and a conductive hearing loss occur at the same time. This type of hearing loss can often fluctuate due to changes in the conductive component of the hearing loss.