Types of Dysarthria Flashcards
Key characteristic of Flaccid dysarthria
Weakness
Lower motor neuron damage (in cranial nerves or spinal nerves) causes what type of dysarthria
Flaccid
What is the final common pathway?
It refers to the final pair of nerves that a neural impulse travels through from the upper motor neurons before it reaches the muscles
This is affected in flaccid dysarthria
Damage to part of the Peripheral nervous system will cause…
Flaccid dysarthria
What main three speech systems are affected in flaccid
Weak resonance muscles
Weak phonation muscles
Weak articulation muscles
What are 6 conditions/ characteristics associated with flaccid
- Muscle paralysis or weakness
- Hypotonicity
- Muscle atrophy
- Hypoactive reflexes
- Diplophonia
- Inhalatory stridor
Thinking of the three main speech systems affected, what are main characteristics of flaccid dysarthria symptoms
-Reduced VP closure causing marked degrees of hypernasality
-Weak VF vibration and increased amounts of air escaping, causing harsh voice quality
-Reduced articulatory contact, causing slow and labored speech
What is the cause of damage that results in flaccid dysarthria
Any disorder disrupting the flow of neural impulses along the lower motor neurons that innervate muscles of respiration, phonation, resonance, articulation, or prosody
What are 5 common causes that result in flaccid
- Physical trauma
- Brainstem stroke
- Myasthenia Gravis
- Guillain-Barre Syndrome
- Polio
What additional, less common causes can result in flaccid
- Tumors in or near brainstem
- Muscular dystrophy due to muscle tissue dying
- Progressive bulbar palsy
What dysarthria is associated with hypoactive oral reflexes & what does that mean?
Flaccid
Diminished or absent oral reflexes (i.e., absent gag reflex)
What is hypotonicity
Reduced muscle tone
Identify the types of physical trauma categories
Surgical injury- accidentally cutting cranial nerve, especially during: Carotid endarectomy, cardiac surgery, removal of head or neck tumors, & dental surgery
or
Head and neck injury (i.e., fall, blow to head, motor vehicle injury)
What is another word for a brainstem stroke?
Cerebrovascular accident (CVA)
What is a brainstem stroke
interruption of blood flow to the brain as an artery breaks or is blocked
Can a single brainstem stroke cause damage to more than one cranial nerve?
Yes, a single brainstem stroke can damage 1+ nerves, with degree of impairment depending on the number of LMN’s lost
What is myasthenia gravis
A chronic autoimmune disorder affecting the neuromuscular junction/involuntary movements, especially of the upper structures, due to antibodies blocking or damaging the muscle tissue
Symptoms of myasthenia gravis
-rapid fatigue of muscular contraction over short time, with recovery after rest
-hypernasality
-decreased loudness
-breathy voice quality
-decreased articulatory precision
How could you assess for myasthenia gravis
Stress test (take a deep breath and count to 100 as rapidly, steady as you can)
reading a lengthy paragraph
How is myasthenia gravis treated?
Temporarily treated with injection of Tensilon (edrophonium chloride)
What is guillain barre syndrome
Demyelization, which often occurs after certain types of injections and immunizations
What are 2 symptoms of Guillain barre syndrome
Flaccid dysarthria
Dysphagia
What is the typical recovery of Guillain Barre syndrome?
High recovery rate, lasting weeks or months
5% die in acute stages
What is polio
Infectious, viral disease that attacks cell bodies of lower motor neurons
Commonly affects the cervical and thoracic spinal nerves
Can also affect cranial nerves
Symptoms of polio
Labored inhalation during speech
Shortened speech phrases
Speaking on residual air (due to low air capacity)
Decreased loudness
Progressive Bulbar Palsy can affect…
Upper and Lower motor neurons
It more often affects lower motor neurons- causing flaccid dysarthria
But can also affect both, upper and lower motor neurons causing mixed dysarthria
What symptoms are the strongest confirmatory sign of flaccid?
Phonatory incompetence and hypernasality
List the 9 major symptoms often seen in flaccid
- hypernasality
- imprecise consonants
- continuous breathiness
- monopitch
- nasal emission
- audible inspiration
- harsh quality
- short phrases
- monoloudness
harsh voice quality is defined as….
Breathiness +hoarseness
How is the respiratory system affected in Flaccid dysarthria
Often not impaired, but if it is will see:
-Impaired control of inhalations and exhalations during speech
-Reduced loudness
-Shortened phrase length
-Strained voice quality if speaking on residual air to prolong phrase length
-Monopitch
-Monoloudness
-Frequent inhalations during speech, which negatively affect prosody
In flaccid dysarthria, impairment to the cervical and thoracic spinal nerves is responsible for what kind of damage?
Damage to the diaphragm and intercostal muscles
Resulting in respiration damage
How is the phonation system affected in flaccid dysarthria
-Incomplete VF adduction, phonatory incompetence
-Breathy voice quality, whisper-like
How is the resonance system affected in flaccid dysarthria
-Hypernasality (most noticable)
-Shortened phrases due to nasal emission
-Weak pressure consonants
How is the articulation system affected in flaccid dysarthria
-Imprecise consonant production
-Reduced articulatory contact due to insufficient elevation of jaw
How is prosody affected in flaccid dysarthriaa
-Monopitch
-Monoloudness
In flaccid, damaged laryngeal muscles adversely affect the ability to make fine VF adjustments for…
Normal pitch and loudness variations
So, prosody is adversely affected
Where is the damage in the brain with spastic dysarthria
Bilateral upper motor neurons in cranial nerves or spinal nerves, affecting the left and right pyramidal and extrapyramidal system tracts
If the pyramidal and extrapyramidal system (desending motor) tracts are damaged on both sides, what is the result?
Spastic dysarthria
Explain descending motor tracts
Neural pathways carrying motor impulses from the cortex to the brainstem and spinal cord OR from the brainstem to the nuclei area
The pyramidal system is responsible for…
Transmitting neural impulses for discrete skilled movements (i.e., speech) down to the Lower motor neurons, which then sends the impulse to the muscles
The extrapyramidal system is responsible for…
Transmitting signals to maintain posture, regulate reflexes, monitor muscle tone, and probably some voluntary movements of the speech mechanism
What Key Characteristic is associated with spastic dysarthria
Stiffness and some weakness
When one descending motor system (either pyramidal or extrapyramidal) is damaged, what is the affect on the other
When one system is damages, the other system will almost always be damaged
If the pyramidal system is damaged, what is the result on speech
Weak, slow skilled movements
Mainly of the lips and tongue
If the extrapyramidal system is damaged, what is the effect on speech
Weakness, increased muscle tone (stiffness), and abnormal reflexes (mainly of the laryngeal and possibly velum muscles)
Which main speech systems are affected in Spastic dysarthria
Stiff, sluggish moving Phonation muscles
Stiff, sluggish moving prosody muscles
What are additional characteristics seen in spastic dysarthria
-Pseudobulbar affect (motor-emotion)
-Drooling (very prominent)
-Spastic paralysis or paresis of the muscles
-Hyperflexia (hyperactive jaw-jerk)
-Little to no muscle atrophy
-Presence of pathological reflexes (sucking reflexes)
What is the possible causes of spastic dysarthria
- Stroke
- Degenerative diseases
- Traumatic head injury
- Viral or bacterial infection of the brain/cerebral tissues
- Brainstem tumor
- Less common cause: cerebral anoxia
What is cerebral anoxia
Lack of oxygen in the blood within the brain
What main two degenerative diseases are causes of spastic dysarthria
-Amyotrophic lateral sclerosis (ALS)
-Multiple Sclerosis (MS)
What is amyotrophic lateral sclerosis
A terminal, degenerative, progressive neurological disease of unknown cause
With a life expectancy of 22 months from time of onset
When amyotrophic lateral sclerosis has mainly upper motor neuron involvement, what is the result?
Spastic dysarthria
When amyotrophic lateral sclerosis eventually affects upper motor neurons and lateral motor neurons, what is the result?
Mixed dysarthria (flaccid-spastic dysarthria)
What is multiple sclerosis?
Suspected immunological disorder resulting in inflammation or complete detruction of myelin sheath covering the axons
This is Demyelinization
A stroke results in spastic dysarthria ONLY when….
- there are two or more cerebral strokes that occur in certain combinations in each hemisphere
OR - One brainstem stroke occurs affecting bilateral upper motor neurons
Keeping in mind the two speech systems mainly affected in spastic dysarthria, what are the main systems
-Incomplete VF closure and hyperadducted VF closure resulting in harsh quality
-monopitch, monoloudness, and short phrases
How is respiration affected in spastic dysarthria
Often doesnt play a great role, but it could have abnormal respiration movements if impaired
-Reduced inhalation and exhalation
-Uncoordinated breathing patterns
-Reduced vital capacity
How is the phonatory system affected in spastic dysarthria
Increased muscle tone of the larynx, causing still and sluggish laryngeal muscles
-harsh (breathy + hoarse) quality due to air leakage
-strained strangled quality due to hyperadducted VFs
-Low pitch due to reduced cricoarytenoid rocking to vary pitch
How is the resonance system affected in spastic dysarthria
Reduced range of motion in velar muscles, causing incomplete VP closure
-Moderate to mild hypernasality (not as bad as seen in flaccid) WITHOUT nasal emission
How is the articulatory system afffected in spastic dysarthria
Articulators range of motion is reduced, reduced contact, and reduced tongue movement (less advanvement and height)
-Imprecise consonant production
-Vowel distortions
In spastic dysarthria, what are the three main reasons for imprecise consonant production
-Abnormally short voice onset time for voiceless consonants
-Incomplete articulatory contact
-Incomplete consonant clusters
How is prosody affected in spastic dysarthria
Prosodic impairment is related to articulatory aspects (tight laryngeal muscles, reducing speed and range of motion)
-Monoloudness due to increased muscle tone
-monopitch due to inability to relax and vary pitch
-short phrased due to reduced range of motion and speech
-Slow rate of speech
Where does the damage occur in unilateral upper motor neuron dysarthria?
Upper motor neuron lesion on one side of the brain, which is supplying impulses to spinal and cranial nerves involved in speech production
What is the key characteristic of unilateral upper motor neuron dysarthria
Weakness or paralysis of the lower face on the OPPOSITE side of the lesion
Why is unilateral upper motor neuron dysarthria typically less severe than bilateral damage?
The cranial nerves innervate most of the speech muscles bilaterally, so if damage occurs they are still receiving impulses from the opposite side
This means the Velum, Pharynx, and Larynx will not be affected structurally
Muscles of the _____ are primarily affected in unilateral upper motor neuron dysarthria. Why?
Lower face & tongue are primarily affected because they primarily ONLY receive unilateral upper motor neuron innervation
Unilateral upper motor neuron dysarthria is primarily a disorder of….
Articualtion, with weakness in lip and tongue muscles
If Left hemisphere damage results in unilateral upper motor neuron dysarthria, what condition/s could co-occur?
Aphasia
Apraxia
If Right hemisphere damage is the result of unilateral upper motor neuron dysarthria, what condition/s could co-occur?
Cognitive deficit
Visual deficit
In unilateral upper motor neuron dysarthria, what causes the UMN damage?
Any condition causing focal damage to the upper motor neurons on the right or left hemisphere
What is the most common condition causing unilateral UMN dysarthria?
Stroke
Frontal stroke is the leading cause
A stroke that occurs within which four areas could result in unilateral upper motor neuron dysarthria
Cortical areas
Subcortical areas
Brainstem
Internal capsule
List the 3 common causes of unilateral UMN dysarthria
- Stroke
-Brain tumor causing focal lesion
-Traumatic brain injury
Most TBI’s result in diffuse lesions, but a focal lesion could occur through…
Shot to the head
Projectile motion of object to head
How is the respiratory system affected in unilateral UMN dysarthria?
It is rarely impaired because of the wide distribution of innervation of intercostal muscles and diaphragm being innervated bilaterally
How is the phonation system affected in Unilateral UMN dysarthria?
Often it is not impaired
If it is, harsh voice quality
When may you see phonation deficits in unilateral UMN dysarthria?
- Mild VF weakness or spasticity
- Previous lesion presenting with new lesion
- Dysphonia (partial loss of voice)
- General medical condition, not attributed to UMN damage
How is resonance affected in unilateral UMN dysarthria
Mild hypernasality
How is the articulation system affected in unilateral UMN dysarthria
Damage causes weakness, reduced range of motion, and decreased fine motor control of the tongue
-Imprecise consonant production
-Irregular articulatory breakdowns
-Slow, irregular, and imprecise AMR
How is the prosody system affected in unilateral UMN dysarthria
Rarely impaired, but if it is: slightly slow rate of speech
Lesion site seen in Ataxic dysarthria?
cerebellum and/or cerebral control circuits (cerebellum neural pathways that connect the cerebellum to other parts of the nervous system)
Function of the cerebellum
regulates muscle tone, maintains balance, and coordinates skilled motor movements by coordinating timing and force of muscle contraction while processing sensory information all over the body and integrating information to execute movements
How does the cerebellum communicate with the CNS?
Through the cerebellar peduncles (3 bundles of neural tracts)
List each of the 3 cerebellar peduncles, briefly what is the function of each
Superior cerebellar peduncle- transmits commands to cortex
Middle cerebellar peduncle- transmits planned movements
Inferior cerebellar peduncle- transmits sensory information
Explain cerebellar control circuits
Neurons that course through three cerebellar pathways and synapse with true UMN within extrapyramidal system or interneurons in the brainstem or spinal cord
NOT synapsing with LMN
What is the key characteristic of Ataxic Dysarthria
(In coordination or lack or order
Disturbed speed, range, and directions of movements/fine motor control)
Which main speech mechanisms are affected in Ataxic?
Articulation
Prosody
Keeping in mind the main characteristics affected in Ataxic, what are main features seen
-Unsteady and slurred speech, imprecise consonants
-Equal and excess stress, prolonged phonemes, prolonged pause intervals
Conditions that can co-occur with Ataxic dysarthria
Limb ataxia
Balance problems
Visual deficits
Cause of damage in Ataxic Dysarthria
Degenerative diseases: -Autosomal dominant cerebellar ataxia of late onset
-Idiopathic sporadic late-onset cerebellar ataxia
-Friedreich’s ataxia (cerebellar ataxia)
-Olivopontocerebellar degeneration
Stroke
Toxic conditions
Metabolic conditions
Traumatic head injury
Tumors
Other causes:
Viral infections invading cerebellum
Infections (syphilis, trichinosis)
Bacterial abscesses
How is the respiration system affected in Ataxic
Paradoxical movements leading to reduced air supply
Can cause: increased speech rate, decreased loudness, harsh quality
How is the phonation system affected in Ataxic
Harsh voice quality
Tremulous phonation
How is the resonance system affected in Ataxic
Mild hypernasality
Intermittent hyponasality
How is the articulation system affected in Ataxic
Imprecise consonant production
Distorted vowels
Irregular articulatory breakdowns
Jerky speech
How is the prosodic system affected in Ataxic
Scanning speech
Equal and excess stress
Prolonged phonemes
Prolonged pause intervals
Monopitch
Monoloudness
Inappropriate silences
Short rushes of speech
Lesion site within basal ganglia or basal ganglia control circuit (extrapyramidal system) can result in?
Hypokinetic dysarthria
Hyperkinetic dysarthria
What is hypokinetic
Reduced movement
What causes in damage resulting in hypokinetic dysarthria
Reduction of dopamine (inhibitor) within nigra striatum, causing increased levels of acetycholine (excitatory)
Hypokinetic dysarthria is the only dysarthria that has….
Increased rate as a symptoms
Mainly one causative factor: Parkinsonism
What are the main speech systems affected in Hypokinetic
Phonation
Prosody
Articulation
What are additional characteristics you may see in hypokinetic
Fasciculations
Oral Tics
What is the key characteristic of hypokinetic dysarthria
Rigidity
Reduced ROM
Slow, but occasionally fast and repetitive movement
Causes of Hypokinetic
Parkinsonism- idiopathic parkinsons, neuroleptic-induced, and postencephalitic
Traumatic head injury
Toxic metal poisoning
Stroke
How is respiration affected in hypokinetic
often not affected, but can be:
Faster breathing rates
Reduced range of respiratory muscles
Shallow breath
Short breath cycles
How is phonation affected in hypokinetic
Harsh quality
Breathy quality
Aphonia
Low pitch
What is the least system affected in hyponasality
Resonance
You may have mild hypernasality
How is articulation affected in Hypokinetic
Imprecise consonants
Repeated phonemes
Palilalia
What is palilalia
Compulsive, increasingly rapid repetitions of word or phrase
How is prosody affected in hypokinetic
Monopitch
Reduced stress
Monoloudness
Inappropriate silences
Short rushes of speech (stop and go quality)
What is the key characteristic of hyperkinetic
Involuntary (increased) movement
What is the main speech system affected in hyperkinetic
Prosody and rate
Causes of hyperkinetic
Chorea
Myoclonus
Tic Disorder
Essential Tremor
Dystonia
What are 4 disorders where dystonia is present?
Spasmodic dysphonia
Spasmodic torticollis
Drug induced dystonia
Meige syndrome
What is chorea?
Random, involuntary movements of limbs, trunk, head, and neck
Will look like dance-like movements
Unpredictable, purposeless, jerky/abrupt movements appearing smooth and coordinated
How is respiration affected in chorea-hyperkinetic
Rapid, unexpected inhalations and exhalations
How is phonation impaired in chorea-hyperkinetic
Harsh quality
Excess loudness variations
Strained and strangled voice
Intermittent breathiness
Voice stoppages
How is resonance affected in chorea-hyperkinetic
Hypernasality
How is the articulation system affected in chorea-hyperkinetic
Imprecise consonant productions
Distorted vowels
Prolonged phonemes
How is prosody affected in chorea-hyperkinetic
Prolonged intervals between syllables and words
Variable speech rate
Monopitch
Monoloudness
Inappropriate silences
Explain myoclonus
Involuntary and brief contractions of whole, part, or groups of muslces simultaneously
Explain tic disorder
Rapid movement that can be controlled voluntarily for a time, but performed frequently due to compulsive desire to perform movement
What types of tics are there?
Motor tics- facial twitches, rapid blinks, grimaces, shoulder shrugging, squatting, hopping, hand gestures, etc.
Voice tics- throat clearing, grunting, barking, palilalia, shorting
How does stress affect tics
Stress can increase the frequency of tics
Tics can also evolve over time
What is essential tremor
Idiopathic, benign hyperkinetic movement disorder causing movements most often affecting the hands, arms, or head occurring during actions
Disappearing when at rest
What is the most common hyperkinetic movement disorder
Essential tremor
Explain dystonia
Hyperkinetic movement disorder of muscle tone, causing involuntary and prolonged muscle contractions interfering with normal movement or posture
Contractions during dystonia are characterized as…
Waxing and waning quality
Appearing and disappearing
How is respiration affected in dystonia-hyperkinetic
Not very impacted
How is phonation affected in dystonia-hyperkinetic
Harsh quality
Strained and strangled
Excess loudness variations
How is resonance affected in dystonia-hyperkinetic
Not very impacted
How is articulation affected in dystonia-hyperkinetic
Imprecise consonants
Distorted vowels
Irregular articulatory breakdowns
Prolonged phonemes
How is prosody affected in dystonia-hyperkinetic
Monopitch
Monoloudness
Inappropriate silences
Short phrases
