How the ear works

The ear is a complex organ comprised of three main structures; the outer ear, middle ear and inner ear.

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The outer ear – this comprises the external part of the ear that is visible (the pinna) which acts like a collecting dish to collect sound waves and direct them into the ear canal. The ear canal is approximately 2.5cm long before the eardrum is reached. The eardrum vibrates as sound waves reach it and transfers the sound energy into the middle ear.

The middle ear – this contains 3 small bones (the ossicles). As the eardrum vibrates, the ossicular chain is caused to vibrate also and transfers the sound energy across the middle ear space. When people suffer from congestion, pressure or fluid in the middle ear can cause them to feel ‘blocked up’. If this congestion continues over time, it can cause some hearing loss which may be temporary. Infection within the middle ear can also cause some hearing loss.

The inner ear – this comprises the cochlea which is a spiral shaped organ. As the ossicles in the middle ear vibrate, they cause movement within the fluid in the cochlea. As the fluid moves, small hair cells are caused to move and these change the mechanical energy from the sound waves into electrical energy which can the travel along the auditory nerve to the brain. Over time, hair cells in the cochlea can become damaged due to ageing or excessive noise exposure and cause hearing loss. The balance organs are also within the inner ear and are also fluid filled structures. As we move, the movement of the fluid within the balance organs tells us about our position in space along with input from our vision and muscles and joints. Sometimes things can go wrong within the balance organs and more can be read about this within the balance section on the website.