Nerve
Hypoglossal nerve (CN XII)
Motor to the tongue
High-yield
Purely motor to the tongue (except palatoglossus); a lesion makes the protruded tongue deviate TOWARD the damaged side. Exits the hypoglossal canal.
Overview
The twelfth cranial nerve, supplying the intrinsic and most extrinsic muscles of the tongue for movement in speech and swallowing.
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Reference facts
- Roots
- Motor (cranial nerve)
- Course
- Exits the skull through the hypoglossal canal and passes into the floor of the mouth to reach the tongue
- Motor
- All intrinsic tongue muscles and the extrinsic muscles genioglossus, hyoglossus, and styloglossus (not palatoglossus)
- Sensory
- No cutaneous sensory territory - this nerve is purely motor.
Clinical correlation
'Lick your wounds' - the tongue deviates toward the side of a hypoglossal lesion.
Frequently asked questions
What type of nerve is the hypoglossal nerve (CN XII)?
The hypoglossal nerve (CN XII) is motor (cranial nerve).
What muscles does the hypoglossal nerve (CN XII) supply?
The hypoglossal nerve (CN XII) supplies the all intrinsic tongue muscles and the extrinsic muscles genioglossus, hyoglossus, and styloglossus (not palatoglossus).
What is the sensory distribution of the hypoglossal nerve (CN XII)?
No cutaneous sensory territory - this nerve is purely motor.
What is the course of the hypoglossal nerve (CN XII)?
Exits the skull through the hypoglossal canal and passes into the floor of the mouth to reach the tongue.