What Is the Function of the Semicircular Canals?

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Semicircular canals are the part of the inner ear associated with balance. These three canals have cilia and fluid to transmit data to the brain on position and balance.

The semicircular canals are three canals used to provide information to the brain on directional balance. Each canal is lined with cilia and filled with fluid called endolympth. As the head and body moves, the fluid moves and pushes the cilia back and forth to create a motion sensor.

The three main parts of the semicircular canals are the horizontal, posterior and superior. The superior is responsible for head rotation, the posterior canal detects movement and rotation on the saggital plane, and the horizontal senses on a vertical basis. Damage to one or more of these canals can result in balance loss and diminished hearing capabilities.

Semicircular canals are quite advanced, with the brain able to compute the angular acceleration felt by the cilia. Tiny floating particles move with the fluid to stimulate the cilia during movement. The semicircular canals form part of the inner ear along with the cochlea and are connected to the auditory nerve. The inner ear is connected to the outer ear by a thin membrane known as the oval window.