Corneal reflex involves which nerves?

Corneal reflex involves which nerves?

• A. V and VI
• B. V and VII
• C. II and III
• D. III and VI

Answer: (A)

The corneal reflex uses a sensory input from the trigeminal nerve and a motor output from the facial nerve. When the cornea is touched, sensory fibers carried by the ophthalmic division of the trigeminal nerve (CN V1) transmit the signal to the brainstem. The signal is then relayed to the facial motor nucleus, and the efferent response travels via the facial nerve (CN VII) to the orbicularis oculi muscle, causing eyelid closure. This reflex tests the integrity of CN V (sensory) and CN VII (motor). The abducens nerve (CN VI) controls the lateral rectus muscle for eye abduction and is not part of this reflex arc, so it isn’t involved in the corneal reflex.

The corneal reflex uses a sensory input from the trigeminal nerve and a motor output from the facial nerve. When the cornea is touched, sensory fibers carried by the ophthalmic division of the trigeminal nerve (CN V1) transmit the signal to the brainstem. The signal is then relayed to the facial motor nucleus, and the efferent response travels via the facial nerve (CN VII) to the orbicularis oculi muscle, causing eyelid closure. This reflex tests the integrity of CN V (sensory) and CN VII (motor).

The abducens nerve (CN VI) controls the lateral rectus muscle for eye abduction and is not part of this reflex arc, so it isn’t involved in the corneal reflex.