Vestibular system
In this lesson, we’ll explore the vestibular system and how it helps you maintain balance, posture, and a sense of spatial orientation.
1) Start with this video:
2) Then, read this article:
Know Your Brain - Vestibular System
3) Watch this video to learn about vertigo, a symptom typically caused by a disruption to the vestibular system or one of the regions it communicates with to maintain our sense of balance and stability:
4) Finally, answer these questions to test your understanding:
1. These fluid-filled structures help our brain to perceive head movement, as when the head is moved the fluid in one of these structures also moves, causing the stimulation of receptors called hair cells:
- A. Eustachian tubes
- B. semicircular canals
- C. lacrimal glands
- D. cochleae
Show Answer
Correct answer: B
The semicircular canals consist of three tubes, positioned approximately at right angles to one another, that are each situated in a plane in which the head can rotate. This design allows each of the canals to detect one of the following head movements: nodding up and down, shaking side to side, or tilting left and right.
2. The sensory receptors (hair cells) of the semicircular canals are found in expansions of the semicircular canals called:
- A. utricles
- B. saccules
- C. ampullae
- D. cochlear ducts
Show Answer
Correct answer: C
The ampullae of the semicircular canals contain hair cells that respond to rotational movements of the head. The utricle and saccule detect linear acceleration, and the cochlear duct is involved in hearing.
3. Which structures of the vestibular system are responsible for detecting linear acceleration (such as forward and backward movement) and gravitational forces?
- A. semicircular canals
- B. otolith organs (utricle & saccule)
- C. cristae ampullares
- D. organs of Corti
Show Answer
Correct answer: B
The vestibular system uses two organs, known as the otolith organs, to detect forward and backward movements and gravitational forces. There are two otolith organs in the vestibular labyrinth: the utricle, which detects movement in the horizontal plane, and the saccule, which detects movement in the vertical plane.
4. These cells are the main receptor cells for both the auditory and vestibular systems:
- A. bipolar cells
- B. Purkinje cells
- C. hair cells
- D. basket cells
Show Answer
Correct answer: C
Hair cells get their name because they have small hair-like projections called stereocilia. The stereocilia deflect in response to mechanical forces, with the result being the production of electrochemical signals used to convey sensory information. Hair cells in the cochlea are responsible for creating signals to transmit information about sound waves, while those in the vestibular system are responsible for creating signals to transmit information about head movement.
5. Which of the following structures/systems is most commonly affected in cases of vertigo?
- A. olfactory cortex
- B. vestibular system
- C. motor cortex
- D. auditory cortex
Show Answer
Correct answer: B
The vestibular system, which includes structures in the inner ear and their connections to the brain, plays a key role in balance and a sense of stability. Vertigo is typically associated with a disruption in function of either the vestibular system or one of the regions it communicates with to maintain our sense of balance.
