A thorough physical examination of cranial nerves requires assessment of which of the following?

A thorough physical examination of cranial nerves requires assessment of which of the following?

• A. Only motor function
• B. Only sensory function
• C. Both motor and sensory function of each cranial nerve
• D. Autonomic function only

Answer: (C)

Cranial nerves carry both motor and sensory information, and many have mixed or multiple roles. A thorough exam looks at the motor function of those nerves that control muscles (such as eye movements, facial expression, tongue movement, and swallowing) and the sensory function of those that convey sensation (such as smell, vision, facial sensation, taste, hearing, and balance). Because nerves can be motor-only, sensory-only, or both, testing both modalities where applicable ensures you don’t miss a deficit. This is why the most complete approach is to evaluate both motor and sensory function of each cranial nerve that has those components, with autonomic aspects considered where relevant.

Cranial nerves carry both motor and sensory information, and many have mixed or multiple roles. A thorough exam looks at the motor function of those nerves that control muscles (such as eye movements, facial expression, tongue movement, and swallowing) and the sensory function of those that convey sensation (such as smell, vision, facial sensation, taste, hearing, and balance). Because nerves can be motor-only, sensory-only, or both, testing both modalities where applicable ensures you don’t miss a deficit. This is why the most complete approach is to evaluate both motor and sensory function of each cranial nerve that has those components, with autonomic aspects considered where relevant.