Facial Nerve (VII) hard

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Questions and Answers

What is the primary role of the larger main motor root of the facial nerve?

Provide motor functions to facial muscles (correct)

Supply sensory information from the external ear

Transmit taste sensations from the anterior tongue

Regulate saliva production in the parotid gland

Which anatomical region does the facial nerve NOT primarily supply?

Muscles of facial expression

Sublingual salivary gland

Lacrimal glands

Muscles of mastication (correct)

What is a critical parasympathetic function of the facial nerve?

Control secretion from the parotid gland

Enable taste sensation in the posterior tongue

Stimulate the contraction of the stapedius muscle

Facilitate saliva production in the submandibular gland (correct)

What is the significance of the chorda tympani branch of the facial nerve?

It transmits taste from the anterior two-thirds of the tongue Signup and view all the answers

Which of the following best describes the course of the facial nerve in the intracranial region?

It travels through the internal auditory meatus Signup and view all the answers

Which of the following functions is NOT associated with the nervus intermedius of the facial nerve?

Motor control of facial muscles Signup and view all the answers

What type of sensory information does the facial nerve relay from the external ear?

Pain signals Signup and view all the answers

Which muscles are primarily innervated by the facial nerve?

Buccinator and orbicularis oculi Signup and view all the answers

In terms of anatomical regions, what is the distinction between the intracranial and extracranial parts of the facial nerve?

Extracranial includes sensory and motor functions Signup and view all the answers

What is the primary function of the greater petrosal nerve?

Parasympathetic innervation to lacrimal and mucous glands Signup and view all the answers

Which structure does the facial nerve exit the skull through?

Stylomastoid foramen Signup and view all the answers

What does the chorda tympani specifically innervate?

Anterior 2/3 of the tongue for taste Signup and view all the answers

Which branch of the facial nerve is responsible for damping loud noises?

Nerve to stapedius Signup and view all the answers

Which of the following is NOT an extracranial branch of the facial nerve?

Oculomotor branch Signup and view all the answers

What type of fibers does the chorda tympani carry to the submandibular and sublingual glands?

Parasympathetic fibers Signup and view all the answers

Which of the following nerves ascends in front of the mastoid process?

Posterior auricular nerve Signup and view all the answers

How many major branches does the facial nerve terminate into after passing through the parotid gland?

5 Signup and view all the answers

What is the role of the motor roots of the facial nerve?

Motor function to muscles of facial expression Signup and view all the answers

Which part of the facial nerve is involved in taste sensation?

Chorda tympani Signup and view all the answers

What is the most common cause of an intracranial lesion of the facial nerve?

Infection related to the external or middle ear Signup and view all the answers

Which symptom is likely to occur if the chorda tympani branch of the facial nerve is affected?

Loss of taste on the anterior 2/3 of the tongue Signup and view all the answers

What type of lesions affect only motor function of the facial nerve?

Extracranial lesions Signup and view all the answers

During which condition might a patient experience hypersensitivity to sound?

Bell’s palsy Signup and view all the answers

Why might the term Bell's palsy be used in cases of facial nerve paralysis?

No specific cause can be identified Signup and view all the answers

Which of the following is NOT a common symptom of a facial nerve lesion?

Loss of peripheral vision Signup and view all the answers

What anatomical feature marks the exit point of the facial nerve in relation to extrinsic lesions?

Stylomastoid foramen Signup and view all the answers

Which of the following conditions is a potential cause of extrinsic facial nerve lesions?

Parotid gland pathology Signup and view all the answers

What could result from severe pressure applied during childbirth concerning the facial nerve?

Extrinsic nerve paralysis Signup and view all the answers

Which symptom is associated with reduced function of the lacrimal gland due to facial nerve damage?

Dry eye Signup and view all the answers

What is the primary function of the posterior belly of the digastric muscle?

Raises the hyoid bone Signup and view all the answers

Which branch of the facial nerve is responsible for supplying the zygomaticus muscle?

Buccal branch Signup and view all the answers

Which of the following muscles does the mandibular branch of the facial nerve supply?

Mentalis Signup and view all the answers

What is the role of the cervical branch of the facial nerve?

Supplies the platysma muscle Signup and view all the answers

Which of the following muscles is NOT supplied by the temporal branch of the facial nerve?

Depressor labii inferioris Signup and view all the answers

Which statement correctly describes the zygomatic branch of the facial nerve?

Supplies the upper part of the orbicularis oculi Signup and view all the answers

Which of the following correctly identifies the function of the buccal branch?

Supplies the orbicularis oris and buccinator Signup and view all the answers

How many terminal branches does the facial nerve typically have within the parotid gland?

Five Signup and view all the answers

What primary function does the platysma muscle serve when supplied by the cervical branch?

Raises the skin of the neck Signup and view all the answers

Which part of the facial nerve is responsible for innervating the auricular muscles?

Temporal branch Signup and view all the answers

Study Notes

Facial Nerve (VII) Overview

The facial nerve is the 7th cranial nerve.
It's associated with the 2nd pharyngeal arch.
It emerges from the brain between the pons and medulla.
It has two roots: a larger motor root and a smaller root called the nervus intermedius.
The nerve passes into the internal auditory meatus.

Function of Facial Nerve

Motor: Controls muscles of facial expression (e.g., orbicularis oculi, buccinator, zygomaticus, platysma).
Sensory: Taste sensation from the anterior two-thirds of the tongue (via chorda tympani).
Sensory: Sensory information from the external ear .
Parasympathetic: Innervates salivary glands (submandibular and sublingual), lacrimal gland, nasal, palatine, and pharyngeal mucous glands.

Anatomical Course

Intracranial: The nerve travels through the cranial cavity.
Extracranial: The nerve exits the cranium via the stylomastoid foramen and travels through the parotid gland.
It branches into 5 major branches:
- Temporal branch
- Zygomatic branch
- Buccal branch
- Marginal mandibular branch
- Cervical branch

Branches of Facial Nerve

Temporal branch: Supplies muscles for eyebrow movements, and the frontalis and orbicularis oculi
Zygomatic branch: Supplies muscles around the eyes and upper lip.
Buccal branch: Serves the muscles for mouth movement, including orbicularis oris, buccinator.
Marginal mandibular branch: Supplies the lower lip and chin muscles.
Cervical branch: Supplies the platysma muscle (neck). This muscle helps move the skin of the neck.
Posterior auricular branch: Innervates muscles of the outer ear and the occipital portion of the occipitofrontalis.

Facial Nerve - Damage

Intracranial lesions: Damage to the nerve before it reaches the stylomastoid foramen can be caused by ear infections or stroke.
Extracranial lesions: Damage outside the stylomastoid foramen, often results in paralysis or weakness of facial muscles, potentially from parotid gland problems, infections (like herpes), or surgery.

Clinical Findings & Symptoms

Dry eyes: reduced lacrimal gland function
Dry mouth: reduced salivary gland function
Taste loss: on the anterior 2/3rds of the tongue
Difficulty talking: if facial nerves related to sound production are affected.
Paralysis or weakness: of the facial muscles, resulting in abnormal facial expressions.

Nerve to Stapedius

A branch of the facial nerve responsible for controlling a tiny muscle in the middle ear (stapedius muscle).
Controls the level of sound entering the ear to avoid damage in case of loud sounds.

Trigeminal and Facial Nerve Examination

A clinical diagnostic method for assessing the function of both nerves.

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Description

Explore the crucial roles of the facial nerve, the 7th cranial nerve that controls facial expressions and sensory functions. This quiz covers its anatomical course, including its motor, sensory, and parasympathetic functions. Test your knowledge on this essential nerve and its clinical significance.