Ataxic Dysarthria Flashcards
What is Ataxic Dysarthria?
Distinct MSD produced by damage to the cerebellar control circuit.
Results in decreased coordination in the movement of the speech mechanism
Likely to affect all speech systems, but most easily perceived in articulation and prosody
** A decrease in coordination of movements
Where is the Cerebellum located specifically and has what?
Inferior to the occipital lobe and posterior to the brainstem
- Three cerebellar peduncle connections
- Four anatomic areas
What is the Cerebellum responsible for?
Responsible for balance, movement coordination and movement scaling
Each cerebellar hemisphere contributes to the control of voluntary movement on the..
IPSILATERAL SIDE
- Contain deep cerebellar nuclei for processing
What does the Vermis do in the Cerebellum?
Vermis assists with coordination of gait and posture, keeps center of balance
The motor cortex in the Cerebellum is what?
CONTRALATERAL
Flocculus and nodule (Flocculonodular lobe) assist with coordination of information from..
Vestibular system
- Influence eye movement
- Coordinate axial muscles for balance
What are the 3 Cerebellar Peduncles?
Inferior peduncle
Middle peduncle
Superior peduncle
What is the function of the Inferior Peduncle?
Receives sensory information about body position
Can provide emergency reflexive information to body
What is the function of the Middle Peduncle?
Takes input from cortex (e.g., motor plan) into cerebellum
Smooths and refines movements
Main output channel to superior CNS
Completes corticocerebellar control circuit
What word is Ataxic Dysarthria?
INCOORDINATION
Ataxic Dysarthria Info
Difficulty with motor EXECUTION resulting in impairments in control of the timing, force or coordination of movement
Any sign of weakness is due to miscalculation of the amount of force required
- These are NOT issues with final common pathway/flaccidity
Reduced range of motion is due to miscalculation of distance needed to move
- These are NOT issues with stopping/starting movements like basal ganglia
What are the Physical Clinical Characteristics?
Broad-based gait
- Difficulty with balance and center of gravity
Titubation
-Rocking/nodding of the head
Nystagmus
- Issues with cranial nerve VIII and floccular lobe in cerebellum
Dysmetria- the inability to control the distance, speed, and range of motion necessary to perform smoothly coordinated movements.
** You can’t complete movements from point to point. For example, it may be very difficult to grab an object with your fingers. You may underreach or overreach for the object you’re trying to grasp
Hypotonia without muscle atrophy
What are the Non-Speech Oral Characteristics?
Typically normal size, strength and symmetry of musculature
Normal gag reflex with no abnormal reflexes
Difficulty with coordinated, repetitive movements
- a.k.a. Dysdiadochokinesis (DDks)
- AMRs/SMRs, Tongue side-to-side, or Smile-pucker-smile of lips
What are the Common Speech Characteristics?
Irregular speech AMRs are a hallmark of ataxic dysarthria
Articulatory inaccuracy
- Imprecise consonants
- Irregular articulatory breakdowns
- Distorted vowels
Prosodic Excess
- Equal and excess stress – can be compensatory
- Prolonged phonemes and intervals between them creating slower rate
Phonatory/Respiratory
- Uncontrolled variations in pitch or loudness
AMRs and SMRs best way to look a diagnosis for ataxic dysarthria
Additional Speech Characteristics
Telescoping– Inconsistent breakdown of articulation in which a syllable or series of syllables are unpredictably run together
Voice tremor (around 3 Hz)
Intermittent mild hyponasality and hypernasality – due to timing errors between muscles of velum and rest of speech mechanism
What are the etiologies?
Friedreich’s ataxia
Hereditary Spinocerebellar Ataxias (SCAs)
Multiple Sclerosis affecting the cerebellar control circuits
Miller-Fisher syndrome
Cerebellar Stroke
Neoplasms
Traumatic brain injury
Toxicity
Normal Pressure Hydrocephalus
Infections
Friedreich’s ataxia
Progressive & hereditary (autosomal recessive)
Begins in early 20s, with a prevalance of ~2 per 100,000
Gait disturbance, dexterity impairments, dysarthria, visual disorders
Lifespan of around 20 years post-diagnosis
Hereditary Spinocerebellar Ataxias (SCAs)
Multiple subtypes, total prevalence ~ 4 per 100,000
Onset ranges across the lifespan
Miller-Fisher syndrome
Rare subtype of Guillain-Barre that shows signs of ataxia
Attacks the cerebellum
Same viral onset, autoimmune disease
Cerebellar Stroke
Superior cerebellar artery, Posterior-inferior cerebellar artery or Anterior-inferior cerebellar artery
Neoplasms
Cerebellar tumors may also put pressure on brainstem or cranial nerves as they exit
16% of metastatic brain tumors develop in the cerebellum
Toxicity
Alcohol abuse/poisoning
Lead or mercury poisoning
Excessive levels of certain prescription drugs, including some anticonvulsants
Normal Pressure Hydrocephalus
Enlarging of the ventricles from excess cerebrospinal fluid
Associated with TBI, hemorrhages, meningitis
Triad of progressive symptoms
- Gait disturbance
- Impaired cognitive function
- Urinary incontinence
Infections
Lyme Disease
Prion diseases
- Creutzfeld-Jakob Disease
- BSE (Mad Cow)
Treatment Notes
Strength training is not supported by evidence
Surgery and prosthetics are generally not used
Minimal evidence for pharmacological support
Behavioral treatments are the standard
** USE AMR’s TO TEST ATAXIA
Treatment Options
Rate reduction
Contrastive stress tasks
Phonetic placement
Minimal pairs
Intelligibility drills
ATAXIC CHART
—->
ATAXIC = TELESCOPING
- Sudden jerk movement (unintentional)
RESPIRATION
- Uncontrolled variations in loudness
- Explosive loudness
PHONATION
- Uncontrolled variations in pitch or loudness
RESONANCE (refers to the way airflow for speech is shaped as it passes through the pharynx (throat), oral (mouth) and nasal (nose) cavities)
- Intermittent mild hypernasality due to timing errors between muscles of the velum and rest of speech mechanism
ARTICULATION
- Articulatory imprecision
- Imprecise consonant
- Irregular articulatory breakdowns
- Distorted vowels
PRODOSY (pitch, loudness, duration of voice)
- Prosodic excess (big changes in loudness and pitch)
- Equal and excess stress- can be compensatory (scanning)
- Prolonged phonemes and intervals between them creating slower rate
NON SPEECH
- No atrophy or fasciculations
- NO MUSCLE TIGHTNESS
- NORMAL gag reflex with no abnormal reflexes
- Difficulty with coordinated repetitive movements aka AMRS/SMRs (tongue side to side, or smile pucker smile of lips)
NEUROANATOMY
- Control circuits (CEREBELLUM)
