All Ears

From infections to hearing disabilities, you may think you’ve heard it all when it comes to the ear. This complex system of tiny parts not only helps us to process sound but also keeps us balanced and performing well during physical exercise.

The structure has three parts: outer ear, middle ear and inner ear.

The outer ear is composed of the pinna, or auricle—the rounded cartilage visible outside—and the auditory canal, which connects to the middle ear through the tympanic membrane, or the eardrum.

The middle ear includes

• the ossicles, three small bones that vibrate and transmit sound waves to the inner ear; and
• the eustachian tube, a mucus-lined canal that connects to the back of the nose and helps to equalize pressure on both sides of the eardrum.

Finally, the inner ear comprises

• the cochlea, a spiral-shaped nerve receptor that translates sound vibrations into electrical impulses for the brain; and
• the vestibule and semicircular canals, which contain receptors that regulate our sense of equilibrium.

Sources: Kacker, Pierce-Smith & Karlin 2019; Bradford 2016.

Here are more sound facts that you may not have heard about ears:

• Aerobic exercise has been shown to improve ear health, since cardiovascular fitness ensures an ample supply of oxygen-rich blood to the ears and surrounding organs (Patino 2010).
• In the cochlea, researchers have identified a biological circadian clock that controls how well hearing damage heals at different times of the day—a discovery that may influence future treatment of hearing disabilities (Karolinska Institutet 2014).
• Eating a healthy diet that includes antioxidants, omega-3 fatty acids and a variety of vegetables can reduce the risk of hearing loss (BWH 2019; Le Prell et al. 2011).
• The ear’s reputation for endless growth rings true: As people age, the ear’s circumference increases, on average, about half a millimeter per year, due to age-related changes in collagen (Bradford 2016).
• Stress and anxiety can increase the production of earwax, also called cerumen, since this protective substance is produced by the same class of glands that secrete sweat as an emotional response (HuffPost 2014; Bradford 2016).