Vestibular System

A 35-year-old female presented to the otolaryngology clinic with recurrent episodes of vertigo, fluctuating hearing loss, and tinnitus in her left ear. The patient reported a sensation of fullness or pressure in the affected ear during these episodes. Audiometric testing revealed sensorineural hearing loss, and vestibular function testing confirmed peripheral vestibular dysfunction. What is the underlying cause of this patient's condition?

• Trauma to the outer ear leading to inner ear damage
• Autoimmune response attacking the inner ear
• Genetic mutation affecting vestibular function
• Excess buildup of fluid in the inner ear
• Infection of the middle ear causing inflammation

The sensory system that processes information regarding self-motion, head position, and spatial orientation is the _______ system

• Visual

• Auditory

• Vestibular

• Olfactory

• Gustatory

After stereocilia move toward the kinocilium,

• mechanically-gated channels close.

• the hair cell hyperpolarizes.

• there is an efflux of calcium.

• there is a decreased release of transmitter from the hair cell.

• there is increased signaling in the vestibular nerve.

Tags

NGSS.HS-LS1-3

Which of the following would be a symptom of nonfunctional otoconia?

• Increased sensitivity to head movements.

• Detection only of vertical movements.

• Detection only of horizontal plane movements.

• Detection only of rotational movements.

• Decreased sensation of head movements.

What type of movement do the saccule and utricle respond to, respectively?

• Vertical; rotational

• Vertical; horizontal

• Rotational; vertical

• Horizontal; vertical

• Horizontal; rotational

The hair cells extend out of the _______ in the _______ of the semicircular canals.

• crista; ampulla

• cupula; ampulla

• cupula; crista

• ampulla; otolith

• otolith; cupula

Which reflex allows a person to visually focus on an object as the head rotates?

• Vestibulocervical reflex

• Vestibulospinal reflex

• Vestibulo-ocular reflex

• Vestibular-cerebellar reflex

• Vestibulomotor reflex

Due to the vestibulo-ocular reflex, which muscles contract when the head moves to the right?

• Left lateral rectus and right medial rectus.

• Left lateral rectus and left medial rectus.

• Right lateral rectus and left medial rectus.

• Right lateral rectus and right medial rectus.

• Left lateral rectus and right lateral rectus.

How does the body maintain posture and balance via the vestibulospinal reflex?

• Inhibitory signals are sent to extensor muscles in the trunk and limbs via the medial longitudinal fasciculus.

• Excitatory signals are sent to extensor muscles in the trunk and limbs via the vestibulospinal tracts.

• Excitatory signals are sent to flexor muscles in the trunk and limbs via the vestibulospinal tracts.

• Excitatory signals are sent to extensor muscles in the trunk and limbs via the medial longitudinal fasciculus.

• Inhibitory signals are sent to extensor muscles in the trunk and limbs via the vestibulospinal tracts.

Tags

NGSS.HS-LS1-3

A 50-year-old male was admitted to the intensive care unit following a severe traumatic brain injury resulting from a motor vehicle accident. Despite efforts to stabilize his condition, the patient remained unresponsive with no signs of spontaneous breathing or brainstem reflexes. To assess for brain death, clinicians performed the vestibular-ocular reflex (VOR) and Doll's Eyes tests. If the patient's brainstem function is still in tact, what would you expect to see regarding their VOR?

• Abnormal VOR responses with eyes moving in the same direction as head movement
• VOR responses with eyes moving slowly and out of sync with head movement
• Complete absence of eye movement during VOR testing
• VOR responses with eyes moving randomly and not following head movement
• Normal VOR responses with eyes moving in the opposite direction of head movement