How do vestibular receptors detect linear acceleration and gravity?

Vestibular receptors detect linear acceleration and gravity through the utricle and saccule, which are known as the otolith organs.12

Each of these organs contains a sensory patch called a macula, which consists of hair cells covered by a gelatinous otolithic membrane. This membrane is embedded with dense, calcium carbonate crystals called otoconia, which add significant mass to the structure.342

When the head undergoes linear acceleration or tilts relative to gravity, the inertia of the heavy otoconia causes the otolithic membrane to shift. This movement creates shearing forces that deflect the cilia of the underlying hair cells. This deflection alters the rate of nerve impulses sent to the brain, providing essential information about head position and movement. The utricle is primarily oriented in the horizontal plane, while the saccule is oriented in the vertical plane, allowing the system to detect acceleration and gravitational orientation in multiple directions.3542