Dysarthria and Motor Speech Disorders Flashcards Preview

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Flashcards in Dysarthria and Motor Speech Disorders Deck (44)
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1
Q

Motor speech disorders

A

Resulting from neurological impairments affecting the motor planning, programming or execution of speech

2
Q

Apraxia of Speech

A

Impacts the retrieval, activation and sequencing of motor plans for speech

3
Q

Dysarthria

A

Impacts the execution of movements for speech

4
Q

Motor Skills involved in Speech Production

A
Phonation - phonatory system
Resonation - velar-pharyngeal system
Articulation - articulatory system
Respiration - respiratory system
Controlled by the cerebral cortex (primary motor cortex), other control centres (cerebellum, basal ganglia)
5
Q

3 Levels of the Motor System

A

Strategy - cerebral cortex and basal ganglia
Tactics - Motor cortex and cerebellum
Execution - brainstem and spinal cord

6
Q

Use of sensory info

A

important for determining starting position of the muscles

Sensory info during = important for adapting planning and execution of movement

7
Q

Frontal lobes in Motor Planning

A

Prefrontal Cortex - planning of movements
Premotor cortex - organises motor sequences
Primary motor cortex - produces specific movements

8
Q

Motor Cortex Representation

A

Part of the body to be moved
Spatial location where the movement is directed
Movement’s function

9
Q

Corticospinal motor pathway

A

(30% of fibres)
- travels from cortex to spine
- controls voluntary movements of the skeletal muscles
- activates spinal motor neurons
Originate from the upper 2/3 of PMC, premotor cortex, sensory cortex

10
Q

Corticobulbar motor pathway

A

(70% of fibres)
- travels from cortex to brainstem
- controls the facial and associated muscles
- activates cranial nerve nuclei in brainstem (UMN)
Originate from the lower 1/3 of the PMC and adjacent area
Controls the skeletal muscles of head and face via cranial nerve

11
Q

Corticospinal Tract

A

Motor cortex - contralateral organisation to output and input
Majority of corticospinal axons cross midline in the medulla to innervate contralateral spinal output nuclei

12
Q

Upper Motor Neuron Damage

A

Weakness, increased tone, hyperreflexia (overactive reflexes)

13
Q

Lower Motor Neuron Damage

A

Flaccidity, severe weakness, atrophy of muscle, hyporeflexia (underactive/absent), fasciculations (twitch)

14
Q

Cranial Nerve Nuclei

A

Found in the brainstem
Can be connected to several related nerves
LMN nuclei - innervated by the UMN of the corticobulbar tracts
Majority receive bilateral innervation (safety)
- Both L and R nerves in pair are innervated by crainal nerves in L and R hem; except lower facial nerve (VII), hypoglossal nerve (XII)

15
Q

Cranial Nerves Specific for Speech/Swallowing

A
CN V - Trigeminal 
CN VII - Facial 
CN IX - Glossopharyngeal 
CN X - Vagus
CN XII - Hypoglossal
16
Q

Testing Muscle Function

A
Symmetry 
Muscle bulk (signs of wasting, atrophy) 
Muscle tone
- hypotonia 
- hypertonia 
Muscle strength
Reflexes - hyper/hyporeflexia 
Coordination
17
Q

Ipsilateral

A

innervates the same side

18
Q

Contralateral

A

Innervates the opposite side

19
Q

Unilateral

A

Innervates one side only

20
Q

Bilateral

A

Innervates both sides

21
Q

Decussation - Corticospinal tract

A

Majority decussate midline in medulla to innervate contralateral spinal output nuclei
Become two lateral corticospinal tracts to innervate contralateral side
Nerves that don’t cross = anterior corticospinal tracts, innervate ipsilateral side

22
Q

Decussation - Corticobulbar Tract

A

Do no decussate
except:
CN I - optic nerve & CN IV - trocholear
CN VII - facial & CN XII - hypoglossal

23
Q

Basal Ganglia

A

Collection of subcortical nuclei within forebrain
Receives input from cortex (neocortex, limbic cortex), midbrain (substatia nigra)
Sends output to motor cortex and substantia nigra

24
Q

Basal Ganglia Structure

A
  1. Caudate nucleus
  2. Putamen
  3. Globus Pallidua
    Subthalamic nucleus, substatia nigra and red nucleus are functionally related to BG
25
Q

Circuitry of Basal Ganglia

A

Caudate and putamen - major input nuclei to basal ganglia; integrates sensorimotor info
Caudate and putament connect with the substantia nigra
Substantia nigra and globus pallidus are the major output nuclei

26
Q

Volume hypothesis

A

Internal globus pallidus = volume dial

Projects into thalamus, projects into motor cortex

27
Q

Direct pathway into Basal Ganglia

A

Amplifies force of movement
Increases cortical activity
- can see abnormal, violent, involuntary movements
- hyperkinetic

28
Q

Indirect Pathway into Basal Ganglia

A

Reduces force of movement
Reduces cortical activity
- diminished, reduced, small, slow movements
- hypokinetic

29
Q

Basal Ganglia Function - Speech

A

Roles in speech execution and motor programming (between formulator and articulator)
Involved in the specification of individual movements
- sets force, range, rate of movement
- involved in specifying volume, speed, stress etc involved in motor program dependent on context/communicative intent

30
Q

Impairments - Basal Ganglia

A

Hyperkinetic symptoms - excessive involuntary movements (Huntington’s Disease)
Hypokinetic symptoms - paucity of movement (Parkinson’s Disease)

31
Q

Parkinson’s Disease - Symptoms

A

Motor tremors, rigidity, loss of balance/coordination, difficulty moving
Resting tremor
Bradykinesia (slowness in initiating/performing movement)
Reduced postural reflexes
Hypokinetic dysarthria
Decrease in non-verbal communication

32
Q

Parkinson’s Disease - Pathology

A

Destruction of neurons that produce dopamine in substatia nigra

33
Q

Parkinson’s Disease - Executive Function

A

20% will develop frank dementia
Often associated with Lewy Body dementia
Subtle cognitive impairments common (esp executive difficulties)

34
Q

Huntington’s Disease - Symptoms

A

Involuntary movements
- chorea (writhing of body, facial grimacing)
Cognitive decline
Psychiatric features

35
Q

Huntington’s Disease - Pathology

A

Cell loss in the caudate nucleus
- lesser degree in putament, globus pallidus and cortex
Autosomal dominant condition

36
Q

Huntington’s Disease - Speech

A

Hyperkinetic dysarthria - inappropriate silences, intermittent breathiness, hypernasality, loudness variations and imprecise articulations; lingual chorea (vocal tics)

37
Q

Huntington’s Disease - Cognitive and Language

A
Impaired delayed recall of info
Impaired memory
Poor cognitive flexibility and abstration
Impaired attention and concentration
Slowed thought process

Language difficulties could be a result of more general cognitive difficulties;
loss of convo initiative
reduced syntactic structure
reduced verbal fluency

38
Q

Cerebellum

A

Sequencing, timing, fine motor control of movement

39
Q

Cerebellar Lesions

A

Ataxia - uncoordinated and inaccurate movements

Dysmetria - overshoot/undershoot target

40
Q

Cerebellum Structure

A
Separated into two hemispheres by the vermis 
Lobes:
- Vestibulocerebellum
- Spinocerebellum
- Cerebrocerebellum
41
Q

Cerebellum - Motor Functions

A

Regulation of motor planning and control of movements (reaching and acquiring targets)
Refinement and amplification of movement online
Motor programming role - parameters for executrion

42
Q

Cerebellum - planning

A

Receives info from the motor cortex about intended movement
- determines order of muscular contractions, timing, ranges and force
- info from vestibular system to maintain posture, balance, refine movement
Info is sent back to primary motor cortex after modification

43
Q

Cerebellar Damage

A
Ipsilateral signs 
Incoordination of the limbs 
Ataxia 
Reduced fine motor control 
Wide based gait 
Dysarthria 
Difficulty performing rapid alternating movements
incoordination of thought
44
Q

Ataxia - Articulation

A

Breakdown in motor organisation and control

= slowness and inaccuracy in range, force, timing, direction of articulatory movements