Chapter 12: The Vestibular System and Eye Movements

Chapter 12: The Vestibular System and Eye Movements

After a brain stem stroke, a person experiences vertigo. Which of the listed arteries likely produced this neurological sign?

A. Superior cerebellar

B. Posterior inferior cerebellar

C. Vertebral

D. Posterior spinal

Comment: The posterior spinal artery supplies the dorsolateral medulla, but caudal to the vestibular nuclei. The anterior inferior cerebellar artery supplies more rostral portions of the vestibular complex.

The ascending vestibular pathway projects to the _________ nucleus of the thalamus, where __________ information is integrated with vestibular sensory messages for perception.

A. ventral posterior; proprioceptive

B. medial geniculate; auditory

C. medial dorsal; cognitive

D. ventral posterior; visceral sensory

The vestibulospinal tracts are part of which of the following descending systems?

A. Lateral

B. Medial

C. Ventral

D. Lateral and medial

Comment: Despite its name, the lateral vestibulospinal tract is a medial pathway.

Ocular depression is produced by contraction of which of the following extraocular muscles?

A. Inferior rectus

B. Inferior rectus and medial rectus

C. Inferior rectus and inferior oblique

D. Inferior rectus and superior oblique

A person has a lesion that damaged the oculomotor nerve. Which of the following best describes the position of the affected eye in this person?

A. Elevated and adducted

B. Elevated and abducted

C. Depressed and abducted

D. Depressed and adducted

Comment: Eye position after third nerve lesion is considered “down and out.”

Palsy of the fourth nerve does not produce _________.

A. horizontal diplopia

B. torsional diplopia

C. a head tilt away from the affected eye to compensate for weakened ocular intorsion

D. vertical diplopia that becomes worse when ...