What happens to endolymph in the semicircular canals when the head stops moving?

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Cross-section diagram of the human ear showing the outer ear, middle ear, and inner ear, with labeled parts including the auricle, auditory canal, tympanic membrane, ossicles, cochlea, semicircular canals, and nerves. — human ear Structure of the human ear.

When the head stops moving, the endolymph within the semicircular canals does not stop instantly due to its inertia; instead, it continues to move for a short period.12

This continued motion of the fluid exerts pressure on the cupula, causing it to be deflected in the same direction as the rotation that just ceased. This deflection bends the hair cells, which sends signals to the central nervous system and often results in a sensation of rotation in the opposite direction, as well as dizziness and postrotational nystagmus. The cupula eventually returns to its upright, stationary position through its own elasticity.123