Academic Block 1 UPT Phase 2.5 – Aerospace Physiology (AP 190) Practice Test

The semicircular canals are responsible for measuring angular acceleration in the vestibular system. These three fluid-filled structures are oriented in different planes and work together to detect rotational movements of the head. When the head moves, the fluid within the canals shifts, causing the hair cells located in the ampullae of each canal to bend. This bending generates signals that are sent to the brain, providing information about the direction and speed of head rotations.

The otolith organs, while also part of the vestibular system, primarily detect linear acceleration and gravitational forces rather than angular acceleration. The vestibular nerve transmits the sensory information from the semicircular canals and otolith organs to the brain, but it does not measure acceleration itself. The cochlea, meanwhile, is part of the auditory system and focuses on the detection of sound rather than balance or motion. Hence, the semicircular canals are uniquely designed to sense changes in angular position, making them crucial for maintaining balance and spatial orientation during rotational movements.