What Are the Functions of the Mastoid?

The mastoid (also called the mastoid bone) is a section of the temporal bone, a skull bone that surrounds the ear. The mastoid section is located behind the ear and is made up of small air cells similar in structure to a honeycomb. The mastoid serves several functions of the human body.

Muscle Attachment

• The mastoid process is a cylindrical protrusion located at the lower part of the mastoid. The main function of the mastoid process is to attach various muscles to the skull. These muscles allow for the movement of the head and jaw and give the ability to display facial expressions. The mastoid process is generally larger in men than in women because men possess larger muscles.

Hearing and Balance

• A part of the mastoid is also connected to the inner ear. The air cells of the mastoid interact with the middle of the inner ear. If an ear infection occurs, it could spread to the mastoid bone causing a condition known as mastoiditis. Fluid build-up from the ear infection can drain into the air cells of the mastoid, causing damage. This can lead to hearing loss and balance impairment if left untreated.

Brain Protection

• The skull is the brain's natural protection against injury. However, it can only withstand a certain amount of force before it becomes fractured. Heavy blows to the head can cause damage to the skull, including the mastoid portion. If the skull is damaged, there is a possibility that the brain is injured as well.