Question

A patient develops a tumor of a cranial nerve that leads to difficulty in speaking from a loss of tongue movement. Which cranial nerve is affected?

a. hypoglossal
b. spinal accessory
c. vagus
d. trigeminal
e. glossopharyngeal

Answer 1

The hypoglossal nerve, responsible for controlling the muscles of the tongue, is affected when a patient has speaking difficulties due to loss of tongue movement. Examination of tongue protrusion is a key test for assessing its function. Damage to this nerve can also hint at issues in the neighboring brainstem regions. correct answer is a) hypoglossal .

Step-by-step explanation:

The hypoglossal nerve (cranial nerve XII) is the nerve affected if a patient is experiencing difficulty in speaking due to loss of tongue movement. This nerve is responsible for controlling the muscles of the tongue, which are crucial for speech and swallowing functions.

During a neurological examination, the functionality of the hypoglossal nerve can be assessed by observing the tongue's movements. The genioglossus muscle, which is controlled by the hypoglossal nerve, facilitates tongue protrusion. If a patient can’t move their tongue correctly and shows difficulty speaking, it likely indicates damage to the hypoglossal nerve or its associated brainstem neurons. In contrast, the vagus nerve influences the palatoglossus muscle but is primarily involved in autonomic functions and does not significantly affect tongue movement related to speech.

Problems in speaking due to tongue movement difficulties directly suggest an impairment of the hypoglossal nerve, but can also indirectly indicate potential structural issues within the adjacent areas of the nerve’s location in the brainstem.