Vestibular System

Question 1

What is the vestibular system?

Answer 1

• detects gravity and tilts and turns of the head
• doesn’t always produce readily definable, conscious sensations
• contributes to our sense of balance, maintains an upright head position, and corrects eye movements to compensate for head movements

Question 2

What happens when there are disruptions in the vestibular system?

Answer 2

• dizziness and nausea

Question 3

What is the anatomy of the vestibular system?

Answer 3

• semicircular canals
• otolith organs
• ampulla
• capula

Question 4

What are the semicircular canals?

Answer 4

• 3 ring-like, fluid-filled structures
• detect changes in head rotation

Question 5

What is the ampulla?

Answer 5

• each semicircular canal has one
• bulge
• where the capula is

Question 6

What is the capula?

Answer 6

• gelatinous mass
• pulls open hair cells in response to movement of fluid in the canals

Question 7

What are the otolith organs?

Answer 7

• vestibular sacs
• 2 distinct structures: utricle and saccule
• monitor the angle of the head and linear acceleration of the head

Question 8

What is an otolith?

Answer 8

• in the otolith organs
• a stone of calcium carbonate
• one sits in the horizontal plane, and the other sits in the vertical plane

Question 9

What does an otolith do?

Answer 9

• the weight of the otolith pulls open hair cell ion channels to indicate the angle of the head and whether it is accelerating along a linear path