Question

multiple choice 2 points

which of the following cranial nerves plays a role in the regulation of the autonomic nervous system?
trochlear
glossopharyngeal
trigeminal
olfactory

Explanation:

Identify autonomic cranial nerves

Using the Cranial Nerves and Autonomic Nervous System knowledge points
The autonomic nervous system (specifically the parasympathetic division) includes preganglionic fibers that travel along four specific cranial nerves:

• Oculomotor nerve (CN III)
• Facial nerve (CN VII)
• Glossopharyngeal nerve (CN IX)
• Vagus nerve (CN X)

Evaluate the given options

• trochlear (CN IV): Purely somatic motor nerve supplying the superior oblique muscle of the eye. It has no autonomic functions.
• glossopharyngeal (CN IX): Carries parasympathetic fibers to the parotid salivary gland and visceral sensory fibers from the carotid sinus/body for blood pressure and blood chemistry regulation.
• trigeminal (CN V): Primarily a somatic sensory nerve for the face and motor nerve for muscles of mastication. It does not carry its own autonomic outflow (though autonomic fibers from other nerves hitchhike along its branches).
• olfactory (CN I): Purely special sensory nerve for the sense of smell. It has no autonomic functions.

Therefore, the glossopharyngeal nerve is the correct choice.

Answer:

• trochlear
• glossopharyngeal (Correct answer)
• trigeminal
• olfactory