While taking a history, the nurse observes that the patient's facial cranial nerves (CN VII) are intact based on which behaviors of the patient?
Explanation & Rationale
Choice A rationaleThe sides of the mouth being symmetric when the patient smiles indicate intact function of the facial cranial nerve (CN VII). This nerve controls the muscles responsible for facial expressions, including smiling, frowning, and closing the eyes. Symmetry in these actions suggests that the facial nerve is functioning properly and that there is no nerve damage or weakness.Choice B rationaleThe patient's eyes moving to the left, right, up, down, and obliquely during conversation are functions of the oculomotor nerve (CN III), trochlear nerve (CN IV), and abducens nerve (CN VI), not the facial cranial nerve (CN VII). These nerves work together to control the movements of the eye muscles, enabling the eyes to move in different directions and maintain proper alignment.Choice C rationalePeriodic blinking of the eyelids involves the oculomotor nerve (CN III) and the facial nerve (CN VII). The oculomotor nerve controls the muscles that lift the eyelid, while the facial nerve controls the muscles that close the eyelid. Blinking is a coordinated action involving both nerves, but the observation alone is not sufficient to determine the integrity of CN VII.Choice D rationaleThe patient moistening the lips with the tongue involves the function of the hypoglossal nerve (CN XII), which controls the movements of the tongue. The hypoglossal nerve is responsible for the motor control of most of the tongue muscles, allowing for actions like licking the lips, speaking, and swallowing. It is not related to the facial cranial nerve (CN VII).