Semicircular canals are involved in what function?

• A. Balance and equilibrium
• B. Hearing
• C. Visual processing
• D. Sound amplification

Answer: (A)

Semicircular canals are part of the vestibular system and sense head rotation. Their three canals are oriented in different planes so they detect angular movement in any direction. When you move your head, the fluid inside the canals shifts and bends the hair cells in the ampullae, altering the signals sent to the brain about motion. This information helps the brain adjust posture and coordinate eye movements to keep you balanced and oriented, which is the essence of balance and equilibrium. Hearing, visual processing, and sound amplification involve other structures (the cochlea for hearing, visual pathways for sight, and the outer/middle ear for sound amplification), not these canals.