Speech (Motor speech disorders) Flashcards
Motor Speech Disorders:
A group of disorders that in adults are aquired following…
- Neurological event
- Neurological degenerative process
- structural change (ie surgery)
- > Divided into 2 categories:
1) Dysarthrias
2) Dyspraxia
Dysarthria
Difficulty producing clear speech (individual sounds or connected speech) because of damage affecting muscle tone/co-ordination.
*Dysarthria is a broad term for a range of acquired speech difficulties varying in presentation, dependant on cause.
Hypokinetic Dysarthria
Caused by basal ganglia impairment (often Parkinson’s, or Parkinsonianism)
Basal Ganglia
finetune motor movements. If not working properly, amplitude and range of movement decreased. Reduced feedback, so person may not sense it or can’t change it.
Hypokinetic Dysarthria symptoms:
Often with Parkinson’s/Parkinsonionism
- reduced volume
- Breathy, rough voice (dysphonia)
- reduced articulation (unclear, underarticulation)
- reduced intonation (monotone)
- difficulty with timing
- reduced feedback -> they don’t know they have an issue and/or can’t fix it.
- > sounds like mumbling
Hyperkinetic Dysarthria - causes:
Excess movement of speech aperatus: - Huntington’s, Tardive dyskenesia, Progressive supranuclear palsy, tourette’s, tremor, excess L-dopa.
*Basal ganglia origin
Hyperkinetic Dysarthria symptoms:
- Speech often normal, but with excess movement of jaw, tongue, face etc
- Whole body movements can affect control of respiration and phonation -> affects speech.
Spastic Dysarthria cause:
Bilateral upper motor neurone impairment (must be bilateral, because upper motor neurones inervate both sides).
- Not usually single stroke, except brainstem stroke or multiple strokes.
- maybe traumatic brain injury, CP, MND, tumours…
Spastic Dysarthria symptoms:
- High muscle tone (upper motor neurones receive proprioceptive feedback from muscle spindle fibres, and compensate accordingly. Damage interferes with this feedback - no compensation to relax muscles -> high tone)
- speech sounds tight and slow. Finely controlled movements affected.
- Phonation affected - speech sounds strained/strangled.
- Articulation slow, effortful, imprecise.
- prolonged phonemes, transitions
- Prosody affected because of slow change of transitions.
- May have hyperactive gag reflex.
- Increased emotional lability (laughing/crying at unexpected moment or out of proportion to the moment).
Unilateral Upper Motor Neuron Dysarthria causes:
- Stroke (cortial, subcortical, brainstem)
- Tumors
- surgical damage
Unilateral Upper Motor Neuron Dysarthria symptoms:
CN V, IX and X bilateral innervation (no shoudn’t be effect from single stroke affecting these upper motor neurons)
CN VII Bilateral innervation on upper side of face, but unilateral on lower
CN XII bilateral innervation except for genioglossus muscle (muscle of tongue protrusion).
so: generally respiration, phonation, resonance OK but phonemes at the front of the tongue are affected (/s/, interdentals, /t/ and with CN VII affected, possiblly with /f/ and /v/))
*saying: t-t-t-p-p-p more difficult than k-g (genioglossus) [slowed but not terrible - quite mild effect, slight distortion of some sounds. Good intelligibility].
BUT can see weakness of CN VII and XII so facial weakness and tongue deviation on protrusion.
Clues:
*Tongue deviation -> mild-moderate laminal distortion due to impaired genioglossus (s, +/- V th, t)
*Lower facial weakness -> mild labiodental distortion.
*sudden dysarthria (not progressive, not getting worse)
Dysarthria
Motor speech disorder due to disfunction at motor programming and execution level of speech output.
- can cause disterbance to all subsystems of speech including articulation, resonance, etc..
- 6 different types of dysarthria
Differential diagnosis of dysarthria:
- Case history, lesion site of neurological disturbance…
* Initial observations from the client –> (start creating hypothesis, then test the hypothesis)
Types of Dysarthria:
1) Flaccid Dysarthria (lower motor neurons affected)
2) Spastic Dysarthria (Bilateral upper motor neuron affected)
3) Ataxic Dysarthria (cerebellar lesion)
4) Hypokinetic Dysarthria (Basal Ganglia issue, typically with PD)
5) Hyperkinetic Dysarthria (Basal Ganglia issue)
5) Unilateral Upper Motor Neuron Dysarthria (One sided upper motor lesion)
7) Mixed Dysarthria (Damage at multiple levels)
Flaccid Dysarthria presentation:
- weakened reflexes
- weaker automatic and voluntary movements
- possible hypotonia
- possibly fasiculations of tongue or facial muscles
- hypernasality, breathyness, inhalation stridor, monopitch, mono-loudness
Spastic Dysarthria presentation:
Bilateral upper motor neurons affected:
- negative symptoms: loss of function: loss of skilled movement, effortful, strained or strangled sounding harsh speech with slow rate, maybe drooling and/or dysphagia. short vowel prolongation (evident on sustained ‘ahh’)
- Positive symptoms: hyperactivity of muscles, increased tone of muscles
- Positive Babinski sign (extension of toes instead of flexion)
- clonus
- snout reflex, jaw jerk
- psudo-bulbar affect: involuntary laughing or crying - struggle to control that.
Ataxic Dysarthria presentation:
Due to cerebellar lesion.
- “Drunk speech”
- Broad/wide stance/gait
- abnormal eye movement
- May exhibit hypotonia
- Often normal OMA but maybe abnormal bite marks on tongue or inside of cheeks.
- incoordination and reduced muscle tone resulting in slowness and inaccuracy in force, range and timing of speech movements –> irregular articulatory breakdowns cause ‘drunk’ sounding speech. Varying pitch and loudness, possible hypernasality.
- examine sustained ‘Ahh’ (looking for irregularities in pitch and loudness) - won’t be the same twice.
- finger to nose - won’t quite get there.
Hypokinetic Dysarthria presentation:
[if Parkinsons: *resting tremor, rigidity, bradykinesia (slow movement), loss of postural reflexes (maintaining posture, balance, fluidity of movement)
- Reduced loudness
- reduced pitch range
- short rushes of speech at an accelarated rate
- sometimes inappropriate repetative movements and repetative silences
Hyperkinetic Dysarthria presentation:
[often seen with movement disorders ie Huntington’s, Tourettes…]
- Abnormal rhythmic or irregular/unpredictable rapid or slow involuntary movements superimposed onto and interfere with speech.
- May have loudness variability (maybe in sustained ‘Ahhh’)
- maybe unpredictable articulatory breakdown.
Unilateral Upper Motor Neuron Dysarthria presentation:
- Contralateral hemiplegia or hemiparesis
- Contralateral lingual weakness
- maybe harsh, strained voice that may sound hoarse, but never breathy
- some imprecise consonants, maybe irregular articulatory breakdowns, slow rate
Speech disorders that may be confused with dysarthria:
*Apraxia of speech
*stuttering
BUT…–>Dysarthria will always be cause by a lesion somewhere
(Flowchart) Function: Ideas
Domain: Cognition
Possible Disorders?
- Dementia
- Confusion
- Developmental Delay
(Flowchart)
Function: Sounds, words, grammar
Domain: Language
Possible Disorders:?
- Aphasia
* Language delay
(Flowchart)
Function: Motor Plan
Domain: [Speech] Motor Planning
Possible Disorders:?
- Acquired Apraxia
* Developmental Apraxia
(Flowchart)
Function: Speech Movements
Domain: Speech Execution
Possible Disorders: ?
*Dysarthria
Speech motor planning (motor programming):
Translating linguistic code into speech units. Moving from abstract components into actual speech.
Motor execution:
The process whereby the motor plan results in motor movements (ie. muscle contractions). So motor plan must first be good, to get good execution. And muscles must also behave to get final good execution.
What are the 5 ‘subsystems’ of speech relating to different levels of physiological, anatomical and neurological involvement?
- Respiration
- Phonation
- Resonance
- Articulation
- Prosody
Role of Respiration in Speech:
Provides the subglottic air pressure that is needed to set the vocal folds into vibration.
Phonation:
The production of voice phonemes through vocal fold vibrations in the larynx.
Resonance:
The proper placement of oral or nasal tonality onto phonemes during speech.
Articulation:
The shaping of the vocal airstream into phonemes.
Prosody:
The melody of speech…In most instances, prosody conveys meaning within an utterance through the use of stress and intonation.
What areas does the Association Cortex feed into?
- Basal Ganglia
* Cerebellum
Basal Ganglia (role in motor speech)
Plans and programmes postural, supportive components of motor activity.
Cerebellum and Thalamus (role in motor speech)
Integrates and coordinates the execution of smooth, directed movements.
Extra-pyramidal system (indirect pathway):
Indirect pathway. Mediates involuntary (subconscious) movement - tone, posture… provides essential base for voluntary movements.
Pyramidal (direct pathway) system:
Voluntary movements
All higher systems must go through the Lower motor neuron system to make things move. The lower motor neurons are…?
Cranial and spinal nerves.
Upper motor neurons originate in the motor region of the brain stem. They…
carry information from brain centres that control the muscles of the body, but they can’t leave the CNS, so they synapse with the lower motor neurons which interface with muscle fibres.