How the Ear Works

The ear is a complex and delicate organ. It collects sound waves so you can hear the world around you. The ear also has a second function - it helps you keep your balance. Your ear can be divided into three parts. The outer ear and middle ear help collect and amplify sound. The inner ear converts sound waves to messages that are sent to the brain. The inner ear also senses the movement and position of your head and body so you can maintain your balance and see clearly, even when you change positions.

A Look at your Inner Ear

The hearing and balance canals are made up of hard bone lined by membrane. The canals are filled with a fluid called endolymph. Sound waves cause vibrations of endolymph in the hearing canal, creating sound messages. Movement of endolymph in the balance canal creates messages about the position and movement of your body. Both types of messages travel along the hearing and balance nerve to the brain. The level of endolymph in the inner ear is maintained by a fingerlike organ called the endolymphatic sac.

What Goes Wrong

When you have Meniere's disease, too much endolymph backs up in the canals, a condition called endolymphatic hydrops. Extra fluid causes pressure to build up, so the canals swell and can't work right. This leads to problems with the ear's hearing and balance systems. Pressure in the hearing canal interferes with sound signals to the brain. Signals are blocked (hearing loss), or signals get sent that make you hear ringing or bussing (tinnitus). Pressure in the balance canals causes the balance system to malfunction and make the brain think that you're spinning in circles (vertigo).