Hypokinetic Dysarthria Flashcards
What is Hypokinetic Dysarthria caused by?
Damage in the basal ganglia that reduces production of dopamine from the basal ganglia control circuit.
What does Hypokinetic Dysarthria impact?
Voice
Articulation
Prosody
Rate
Rhythm
Intonation
Stress
(VAPRRIS)
Results in what?
Reduced range of motion and control of volitional motions
What is the Basal Banglia Control Circuit?
Motor relay nuclei responsible for smooth, precise muscle activity
What is it composed of?
Striatum
- Caudate nucleus
- Putamen
Lenticular nuclei
- Putamen
- Globus Pallidus (Internus and Externus)
Subthalamic Nucleus
Substantia Nigra
What are the 4 Basal Ganglia motor functions?
- Regulate the duration of a selected action
- Decide whether another action is of enough importance and value to interrupt the existing action
- Choose when to terminate the current action
- Some movement scaling through timing changes (mostly cerebellar circuit)
What are the two pathways of the Basal Ganglia?
Direct & Indirect
Stop and go commands are controlled by..
Neurotransmitters
Glutamate is
Excitatory
GABA is
Inhibitory
Dopamine modulates which path is
Active
Excites direct pathway and inhibits indirect pathway
Direct Pathway or “ “
GO
Activation of the direct pathway (high dopamine)….
Blocks inhibition
This releases the thalamus and motor cortex to proceed with the motor plan
When this pathway is overactive, what type of movement occurs?
Unintentional
Indirect Pathway or “ “
STOP
Activation of the indirect pathway (low dopamine)…
Inhibits thalamus
This stops excitation of the motor areas and inhibits actions
When this pathway is overactive movement size and duration is
Reduced
What is the one word for Hypokinetic Dysarthria?
REDUCED
**Rushes of speech sounds like “shivering” in the DDKs at a rapid pace
GALLOPING (Horse is HYPO)
What are some Non-Speech symptoms?
- Unilateral Tremor (excess movement from “go”)
- Rigidity of muscles and joints (reduced movement from “stop”)
- Bradykinesia (slowness of movement)
- Facial masking and reduced blink frequency
- Hypokinesia – Reduced volitional movement range
- Reduced gesturing during speech
- Micrographia- consistently small and abnormally small handwriting
- Gait and arm swing
- Festinating gait
- Postural instability
What are some Speech symptoms?
- Dysphonia - hoarseness, breathiness, and/or tremulousness
- Monopitch
- Monoloudness
- Reduced stress
- Variable rate with short rushes of speech
- Consonant and vowel imprecision
- Reduced range of movement of articulators
- Neurogenic Stuttering (acquired onset of repeated phonemes)
What is the most common Etiology?
Parkinson’s Disease
Incidence: 50 per 100,000 people over age 50
Slowly progressive in most cases
Life expectancy after diagnosis ~ 15 years
~40% develop dementia
~90% develop dysarthria
~80% develop dysphagia
Depression is common
Other Etiologies
Vascular Parkinsonism (basal ganglia stroke)
Toxicity due to antipsychotics and other medications
Chronic Traumatic Encephalopathy
Infection (postencephalitic parkinsonism)
- West Nile, HIV (Progressive Multifocal Leukoencephalopathy)
What are some Non-Speech Treatments
Levadopa/Carbidopa for Parkinson’s Disease
- Supplements dopamine produced by the body
- Can result in tardive dyskinesia, dystonia
- Motor function has peaks and troughs as body metabolizes
Deep Brain Stimulation
- Insertion of electrode into the basal ganglia (usually subthalamic nucleus or globus palladus)
- Electrical stimulation acts as substitute for missing dopamine neurotransmitters
- Voltage, firing rate, etc. are adjusted to maximize benefit for the patient
What are some Respiration treatments?
Expiratory Muscle Strength Trainer (EMST)
- Main effect on muscles of exhalation
- Available to purchase publicly ~$50
- Pt blows into device fitted with one-way spring-loaded pressure release valve
- When pressure target is met, valve opens
- 5 sets of 5 breaths, 5 days per week
Inspiratory Muscle Strength Trainer (IMST)
- Main effect for diaphragm
- Be careful with patients who have other additional lung conditions
What are some Speech treatments?
Lee Silverman Voice Treatment
- High-intensity vocal effort with many repetitions
- Focus on increasing sensory awareness of loudness and effort
- Must be certified in LSVT to offer the program
Parkinson Voice Project
Pacing boards for self pacing of rate
Tapping or using a metronome to keep rate and rhythm consistent
Delayed Auditory Feedback (DAF) for neurogenic stutter has shown mixed results
What is the motor function of the Basal Ganglia?
Regulate the duration of a selected action
Decide whether another action is of enough importance and value to interrupt the existing action
Choose when to terminate the current action
Some movement scaling through timing changes (mostly cerebellar circuit)
HYPOKINETIC CHART
—–>
RESPIRATION
- Reduced loudness
- Reduced phrase length
PHONATION
- Hoarsness
- Vocal tremor (occasionally)
- Breathiness (occasionally)
- Decreased pitch range
RESONANCE
- Hypernasality
ARTICULATION
- SHORT RUSHES OF SPEECH with reduced range of motion
PROSODY
- Monotone (flat speech because of facial masking)
- Irregular rate/rhythm caused by the rushes of speech
NON SPEECH
- Facial masking
- Rigid movements (joints locked up), tremors
NEUROANATOMY
- Basal Ganglia damage
