Question

Benign Paroxysmal Positional Vertigo is a disorder where some of the calcium carbonate crystals in the utricle migrate into the semicircular canals. Why does this condition cause periods of dizziness?

Answer 1

Benign Paroxysmal Positional Vertigo causes dizziness because dislodged calcium carbonate crystals from the utricle stimulate the hair cells in the semicircular canals inappropriately by gravity, leading to false signals of movement being sent to the brain.

Step-by-step explanation:

Benign Paroxysmal Positional Vertigo (BPPV) occurs when calcium carbonate crystals, normally found in the utricle, migrate into the semicircular canals of the inner ear. This migration can cause periods of dizziness because the calcium carbonate crystals stimulate the hair cells in the semicircular canals inappropriately. Specifically, these hair cells are sensitive to angular movements, but when the crystals enter the canals and settle on the hair cells, they can be moved by gravity. This results in the brain receiving signals that suggest movement or orientation changes when there hasn't been any, causing the sensation of dizziness or vertigo.

The semicircular canals are a crucial component of the vestibular system, which is responsible for providing the sense of balance and spatial orientation for the purpose of coordinating movement with balance. The canals contain a fluid that moves when the head rotates, and this fluid movement is detected by the hair cells. Normally, these cells respond to rotation, such as turning the head, not to gravitational forces. When the crystals from the utricle dislodge and affect the hair cells, the hair cells send false signals to the brain, triggering vertigo.