Facial Nerve: Motor, Sensory, and Autonomic Functions

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What are the three parts of the facial nerve?

Motor part, 2. Sensory part, 3. Autonomic part

Which areas does the motor part of the facial nerve supply?

Muscles of facial expression, Platysma, Stylohyoid, Stapidus, Posterior belly of digastric muscle

What does the sensory part of the facial nerve convey?

Parasympathetic secretory fibers to submuxillary, sublingual, and lacrimal gland; test sensation from the anterior 2/3 of the tongue

How many branches supply the facial muscles with autonomic fibers?

Five branches: temperament, zygomatic, buccal, mandibular, and cervical Signup and view all the answers

What are the characteristics of a lesion in the facial nerve?

Motor weakness, paralysis, and specific distribution patterns based on the type of lesion (LMNL or UMNL) Signup and view all the answers

What are the differences between upper motor neuron lesion (UMNL) and lower motor neuron lesion (LMNL) of the facial nerve?

UMNL affects the opposite side of the face with sparing of the upper quarter, while LMNL affects the same side of the face and leads to complete paralysis of the lower half of the face. Signup and view all the answers

What is the characteristic feature of Bells palsy?

It is a peripheral facial paralysis of acute onset due to non-suppurative inflammation of the facial nerve within the stylomastoid foramen and peripheral to the geniculate ganglion. Signup and view all the answers

What is the clinical picture of lower motor neuron lesion of the 7th cranial nerve?

The clinical picture includes pain behind the ear, stiffness and numbness of the face, rapid paralysis, inability of facial muscles to respond to stimuli, and impairment of taste over the anterior 2/3 of the tongue on the affected side. Signup and view all the answers

How can lower motor neuron affection be differentiated from upper motor neuron lesion?

Lower motor neuron affection can be differentiated from upper motor neuron lesion by observing the symmetry of the two sides of the face. Signup and view all the answers

What are the causes of lower motor neuron lesion of the 7th cranial nerve?

The causes include vascular ischemia, autoimmune factors, infective factors, and rheumatic factors. Signup and view all the answers

What is the physical evaluation process for lower motor neuron lesion of the 7th cranial nerve?

The physical evaluation involves observation in front of a large mirror, with the child sitting in front of the mirror and the therapist standing behind, or the infant being evaluated while sitting on their mother’s lap. Signup and view all the answers

What are the symptoms of lower motor neuron lesion of the 7th cranial nerve?

The symptoms include pain behind the ear, stiffness and numbness of the face, rapid paralysis, inability of facial muscles to respond to stimuli, and impairment of taste over the anterior 2/3 of the tongue on the affected side. Signup and view all the answers

How does the onset of lower motor neuron lesion of the 7th cranial nerve typically occur?

The onset is characterized by pain behind the ear, which sometimes spreads over the mastoid process, followed by stiffness and numbness of the face, and then rapid paralysis. Signup and view all the answers

What are the gender and age characteristics associated with lower motor neuron lesion of the 7th cranial nerve?

It can occur at any age from infancy to old age and affects both sexes. Signup and view all the answers

How do the facial muscles respond in lower motor neuron lesion of the 7th cranial nerve?

The facial muscles of the involved side fail to respond to voluntary, emotional, or associative stimuli. Signup and view all the answers

What may be impaired in lower motor neuron lesion of the 7th cranial nerve?

There may be impairment of taste over the anterior 2/3 of the tongue on the affected side. Signup and view all the answers

What are the informal and formal evaluations used for lower motor neuron lesion of the 7th cranial nerve?

The informal evaluation includes general and specific observations, while the formal evaluation involves tests for pain, reflexes, adhesion, and muscle strength. Signup and view all the answers

What is the primary function of the motor part of the facial nerve?

Supplying muscles of facial expression (B) Signup and view all the answers

Which part of the brain does the facial nerve's origin, Area 6, belong to?

Frontal lobe (D) Signup and view all the answers

What is the characteristic feature of Bells palsy?

Peripheral facial paralysis of acute onset (A) Signup and view all the answers

Which muscles are supplied by the motor part of the facial nerve?

Platysma and posterior belly of digastric muscle (A) Signup and view all the answers

What type of lesion is characterized by paralysis distribution of the face on the opposite side of the lesion with sparing of the upper quarter of the face?

Upper motor neuron lesion (UMNL) (D) Signup and view all the answers

What are the functions of the sensory part of the facial nerve?

Conveying test sensation from the anterior 2/3 of the tongue (C) Signup and view all the answers

What type of paralysis affects only the lower half of the face?

Complete paralysis affecting muscles of lower half of face (B) Signup and view all the answers

Which part of facial nerve is unilaterally supplied from corticonuclear of opposite side?

-Lower part (D) Signup and view all the answers

(True/False) Facial nerve is a mixed nerve having only motor and autonomic fibers.

False (B) Signup and view all the answers

What is the most common age group affected by lower motor neuron lesion of the 7th cranial nerve?

Young adults (C) Signup and view all the answers

Which symptom is typically experienced after two days of lower motor neuron lesion of the 7th cranial nerve?

Numbness and stiffness of the face (C) Signup and view all the answers

Which evaluation method involves the child sitting in front of a large mirror?

Formal evaluation (D) Signup and view all the answers

What is the main clinical manifestation of lower motor neuron lesion of the 7th cranial nerve?

Facial asymmetry with one side drawn towards the sound (C) Signup and view all the answers

What differentiates lower motor neuron affection from upper motor neuron lesion based on observation?

Symmetry of both sides of the face during closure of the eyes (C) Signup and view all the answers

What is a possible cause for lower motor neuron lesion of the 7th cranial nerve?

Exposure to air draft resulting in vasoconstriction of facial nerve blood vessels (A) Signup and view all the answers

What physical evaluation must be performed in front of a large mirror for children above six years and their therapist?

Muscle test (C) Signup and view all the answers

What is a characteristic feature of Bell's palsy?

Impairment of taste over the anterior 2/3 of the tongue on the affected side (A) Signup and view all the answers

What is typically observed in individuals with lower motor neuron affection in terms of voluntary emotional or associative stimuli?

'Mouth draw towards the sound side' phenomenon (D) Signup and view all the answers

What type of vascular response may contribute to lower motor neuron lesion?

Exposure to air draft leading to vasoconstriction of facial nerve blood vessels (A) Signup and view all the answers

Facial Nerve Parts

The facial nerve has three parts: motor, sensory, and autonomic.

Motor Part of Facial Nerve

Controls facial expression muscles and muscles like platysma, stylohyoid, stapedius, and digastric.