Chapter 16: Vestibular and Visual Systems

Chapter 16: Vestibular and Visual Systems

Complete Chapter Questions With Answers

Sample Questions Are Posted Below

1. The medial longitudinal fasciculus is a bilateral axonal pathway between the vestibular nuclei and which of the following?
2. Cranial nerve nuclei III, IV, and VI
3. Superior colliculus
4. Cranial nerve nuclei XI
5. A and B
6. A, B, and C

ANS: E

Rationale: The medial longitudinal fasciculus (MLF) consists of axons that connect cranial nerves III, IV, VI, and XI and the superior colliculus. The MLF coordinates eye and head movements.

2. Vestibular connections influence which of the following?
3. Posture of the head and body
4. Head and eye movements
5. Consciousness
6. Autonomic functions
7. All of the above

ANS: E

Rationale: The vestibular nuclei are located in the brainstem, at the junction of the pons and medulla. Projections from the vestibular nuclei contribute to sensory information about head movement and head position relative to gravity, gaze stabilization (control of eye movements when the head moves), postural adjustments, and autonomic function and consciousness.

3. Information from the right visual field is conveyed to which of the following?
4. Left lateral geniculate and left visual cortex
5. Right lateral geniculate and right visual cortex
6. Bilateral geniculate then left visual cortex
7. Bilateral secondary visual cortices
8. Right pretectal area of superior colliculus

ANS: A

Rationale: The left half of each retina receives information from the right visual field. Signals from the nasal retina of the right eye cross the midline in the optic chiasm, signals from the temporal retina of the left eye continue ipsilaterally. Thus the information from the right visual field is conveyed to the left lateral geniculate and left visual cortex.

4. What is the most common symptom of vestibular dysfunction?
5. Nausea and vomiting
6. Limb ataxia
7. Disequilibrium
8. Vertigo
9. Upward beat nystagmus

ANS: D

Rationale: The most common symptom of vestibular dysfunction is vertigo. Nausea and vomiting may occur, and disequilibrium may occur due to abnormal vestibulospinal tract signals. Limb ataxia is usually a cerebellar sign. Upward beat nystagmus is unusual and occurs with anterior semicircular canal Benign Paroxysmal Positional Vertigo (BPPV).