Damage to the lower motor neurons in the cranial or spinal nerves (result of damage to the PNS) is______
Flaccid dysarthria
_____ occurs when there is a disorder that disrupts the flow of neural impulses along the lower motor neurons that innnervate the muscles of respiration, phonation, articulation, prosody, or resonance.
People with flaccid dysarthria have weakness in ____ or ______ musculature.
speech or respiratory musculature
Patients with flaccid dysarthria almost always preesent with what symptoms?
slow/labored articulation, mixed degress of hypernasal resonance, and hoarse-breathy phonation.
Flaccid dysarthria patients presenting with slow/labored articulation, mixed degress of hypernasal resonance, and hoarse-breathy phonation is caused by _______
paralysis, weakness, hypotonicity, atrophy, and hypoactive reflexes of involved speech muscualature
what are the 6 pairs of cranial nerves that play a vital role in speech production?
trigeminal, facial, glossopharyngeal, vagus, accessory, and hypoglossal
What processes can harm the 6 cranial nerves involved in speech production?
brainstem stroke, tumors, infections, physical trauma, and surgical accidents.
True or False: not all injuries to these cranial nerves cause every characteristic of flaccid dysarthria.
True
Unilateral damage to the trigeminal nerve can result in ____
weakness or paralysis in the jaw and velar muscles that are on the same side as the damage (though usually the unaffected side of the body is strong enough to compensate for the weak side)
Bilateral damage to the trigeminal nerve causes ______
a serious effect on articulation, and some affect on rate of speech. Affected individuals cannot raise their jaw sufficiently to produce most consonant and vowel phonemes.
Damage to the facial nerve can cause ____
it can affect the muscles of the entire face on the same side as the lesion if it occurs above the point where the facial nerve divides into its cervicofacial and temporofacial branches.
What is a characteristic of facial nerve damage?
facial droop or the eyelid, mouth, cheeck, and other structures on the affected side of the face only.
What is one way to assess the function of the glossopharyngeal nerve?
eliciting a gag reflex
Why is it difficult to determine damage to the glossopharyngeal nerve?
Becuase damage ususally will affect the vagus nerve, a cranial nerve that makes a significant contribution to speech production.
Which of the 6 nerves is one of the most important cranial nerves for speech production?
Vagus nerve. It is very long and has many branches, three of which have special importance for motor speech production: pharyngeal branch, external superior laryngeal nerve branch, and the recurrent nerve branch.
The pharyngeal branch of the vagus nerve provides motor innvervation for the many muscles of the _____
pharynx
damage to the pharyngeal branch of the vagus nerve can affect movement of the velum. Unilateral damage to this branch can result in the affected side of the velum_____
hanging visibly lower than the other side.
What are the characteristics of bilateral damage to the pharyngeal branch of the vagus nerve?
nearly all muscles of the velum will demonstrate weakness or paralysis.
Bilateral damage to the pharyngeal branch of the vagus nerve will or will not result in moderate to severe hypernasality?
It will, all the muscles have been weakened or paralyzed and hypernasality will occur.
It is with unilateral damage that you may not see any hypernasality.
What muscle is essential in controlling vocal pitch?
Cricothyroid muscle of the larynx.
Is innervated by the External Superior Laryngeal Nerve Branch.
1. Unilateral damage to the External Superior Laryngeal Nerve Branch usually results in _____.
2. Bilateral damage to the External Superior Laryngeal Nerve Branch usually results in _____.
1. Only modest difficulty in varying pitch.
2. Decreased loudness, increased breathiness, and notable difficulty in changing vocal pitch.
The recurrent nerve branch of the Vagus nerve supplies the motor innervations to what muscles?
All the intrinsic muscles of the larynx (excluding the Cricothyroid muscle, which is innervated by the external superior laryngeal nerve branch)
Unilateral damage to the recurrent nerve branch of the vagus nerve will cause what?
The vocal fold on the affected side will be fixed in the paramedian position (fold is halfway between abducted and adducted)
A person with unilateral vocal fold paralysis will demonstrate what voice characteristics?
Breathy phonation and decreased loudness
A person with Bilateral vocal fold paralysis will demonstrate what voice characteristics?
Breathy phonation and hoarseness, and inhalatory stridor also may be evident
Bilateral damage to the recurrent nerve branch of the vagus nerve will cause what effects?
Both vocal folds will be affixed in the paramedian position
True or false: the accessory nerve is not a pure cranial nerve.
True. It also contains the neurons that branch out from the spinal cord.
The accessory nerve innervates the intrinsic muscles of ______
Velum, pharynx, and larynx.
True or false: The functions of the accessory nerve are impossible to separate from the functions of the vagus nerve.
True, because the neurons of the accessory nerve are integrated with the neurons of the vagus nerve.
This also means that damage to the accessory nerve will almost always affect the vagus nerve.
Which nerve provides motor innnervations for all the intrinsic muscles of the tongue?
Hypoglossal nerve
Unilateral damage to the hypoglossal nerve results in ______
weakness or paralysis in the half of the tongue that is on the same side as the damage.
Bilateral damage to the hypoglossal nerve results in ______
overall weakness of the tongue and reduced range of movements of the tongue
What is the primary characteristic of an individual with hypoglossal nerve damage?
imprecise articulation;
worse with bilateral damage, with notable distortions on phonemes requireing elevation of the tip of tongue. With unilateral, the distortion is mild because the unaffected side compensates.
What is one of the most important nerves of respiration?
Phrenic nerve; innervates the diaphragm.
Damage to spinal nerves affect ______, which affects speech.
respiration
Damage to the phrenic nerve causes_____
paralysis of the diaphragm, resulting in significantly weakened inhalation.
People with impaired respiratory abilities may demonstrate:
decreased speech loudness as a result of reduced subglottic air pressure, shortened phrases (affecting prosody), and speak on residual air (causing straining quality at end of utterance)
Flaccid dysarthria can affect which of the five parts of speech?
all of them: respiration, phonation, resonance, articulation, and prosody.
What speech characteristic is most common in flaccid dysarthria?
Hypernasality
Which consonants are weakened in flaccid dysarthria?
Plosives, which are weak
What are the characteristics of articulation for people with flaccid dysarthria?
imprecise consonant production, and misarticulations due to jaw movement weakness.
Which of the 5 speech characteristics is the most valuable indicator in diagnosing flaccid dysarthria?
Phonation. Incomplete adduction of the vocal folds causes phonatory incompetance, and there is a breathy voice quality and/or audbile inhalatory stridor.
Flaccid dysarthria sometimes causes weakened respiration; if there is, what are some characteristics of it?
Reduced loudness, shortened phrases, strained voice quality when speaking on residual air.
Can people with flaccid dysarthria have monopitch or monoloudness?
Yes, weakness causes an inability to change pitch and loudness levels. However, this is common with most of the dysarthrias.
Of the many etiologies of flaccid dysarthria, which is related to an infectious viral disease affecting lower motor neurons, affects spinal nerves, and respiratory weakness?
Polio
Of the many etiologies of flaccid dysarthria, which is related to a fatal disease that causes tiredness and rapid fatigue when counting out loud?
Myasthenia Gravis.
Of the many etiologies of flaccid dysarthria, which is related to damage to the cell bodies of the lower motor neurons?
Brainstem stroke
Of the many etiologies of flaccid dysarthria, which is related to demyelinated neurons of the PNS, is characGterized by weakness and numbness in limbs?
Guillain-Barre Syndrome
Of the many etiologies of flaccid dysarthria, which is related to masses growing close to the brain stem?
Tumors.
Of the many etiologies of flaccid dysarthria, which is related to a progressive degeneration of muscle weakness and manifests all over the body (not just speech)?
MS
Progressive bulbar palsy also causes weakness and affects LMN's....
