Motor Speech Disorders Flashcards
Motor Speech Overview
Speech is a sensory and motor process
-Requires coordination of respiration, phonation, resonance, and articulation
Damage to the central (CNS) or peripheral (PNS) nervous systems can cause neurospeech disorders
- Apraxia
- Dysarthria
Cortex
- contains motor and sensory regions responsible for voluntary movement
Broca’s area
- Motor planning area for speech
Supplementary motor cortex
- Works with the premotor area to send motor planning info to the primary motor cortex
Premotor area
- Assists the motor strip in integrating and refining motor movements
Primary motor cortex (motor strip)
- Precentral gyrus located in frontal lobe (have this in left and right hemisphere)
- Homunculus
Cortical motor regions
involved in planning motor movements
Receive information on the motor ‘plans’ from cortical and subcortical structures
Important cortical motor regions:
- primary moto cortex (motor strip)
- premotor area
- supplementary motor cortex
- broca’s area
Direct Activation Pathway
Pyramidal tract
Upper motor neuron system-cortex, brainstem, & spinal cord
Divided into two tracts:
- Corticobulbar
- Corticospinal
Origin- cerebral cortex
Destination-cranial or spinal nerve nuclei
Function-voluntary, skilled movements
Indirect Activation Pathway
Extrapyramidal tract
Upper motor neuron system
Includes:
- Red nucleus-works with cortex for movement of upper limbs (midbrain)
- Reticular Nuclei-Postural set (pons & medulla)
- Vestibular nuclei-balance (floor of 4th ventricle-pons & medulla)
Origin- Cerebral cortex
Destination-Cranial and spinal nerve nuclei
Function-controls posture, tone, & movements supportive of voluntary movement
Control Circuits
Basal Ganglia & Cerebellum
Give their input to cortex
Cortex sends the information down the direct and indirect pathways
They do NOT talk to the lower motor neurons (cranial and spinal nerves)
Cerebellum
Functions:
Coordination
Planning
Maintenance of muscle tone
Basal Ganglia Functions:
Functions:
Helps cortex select the right motor plan
Inhibits unnecessary movements
Lower Motor Neurons
The workers
Origin-brainstem and spinal cord
Destination-Muscle
Functions-
Carry out voluntary movement commands sent from UMNs
Cranial nerves
12 pairs; 7 pairs involved in speech production
Provide motor and sensory information to the muscles of respiration, phonation, resonance, and articulation (face and neck)
Spinal nerves
31 pairs of spinal nerves
Provide motor and sensory information to the muscles of the body (NOT including face and neck)
Apraxia
Error in Motor Planning- Difficulty planning the motor movements for speech
Lesions: Left frontal lobe Left parietal lobe Parts of basal ganglia Insula
Causes: CNS degenerative diseases Trauma Tumor Stroke
More likely to co-occur with Broca’s Aphasia
Characteristics:
- Inconsistent articulatory errors
- Errors increase as word complexity and length increase
- Groping movements of the articulators
- Difficulty initiating speech
- Inaccurate syllable stress
- Slow rate of speech
Apraxia in adults is an acquired disorder
Childhood apraxia of speech is a developmental problem
Dysarthria
– a group of neuromotor speech disorders that result in muscle weakness or loss of muscle control
Site of lesion and respiratory, phonatory, resonance, and articulation characteristics
Flaccid Dysarthria
Site of lesion – lower motor neuron (LMN)
Resulting in muscle weakness or paralysis
Deficits may be seen in 1 or more speech subsystems:
- Respiration
- Reduced vital capacity (can’t take deep breath for speech)
- Shallowing breathing
- Phonation
- Breathy voice or aphonia
- Hoarse voice
- Reduced pitch or loudness
- Monotone & monoloudness
Resonance: Hypernasal
Articulation:
-Imprecise consonants – articulation errors
Associated diseases:
-Moebius syndrome – atypical development of brainstem
-Bell’s palsy – Facial nerve (VII) disorder
Guillian-Barre syndrome- viral infection causes muscle paralysis
-Myasthenia gravis – Loss of synapses resulting rapid weakening of muscles
-Muscular dystrophies – muscles affected by various diseases
Unilateral Upper Motor Neuron Dysarthria (UUMN)
Site of Lesion – Unilateral UMN damage
Cleft hemisphere damage- can co-occur with apraxia or aphasia
Right hemisphere damage- can co-occur with cognitive deficits or prosody deficits
Speech deficits are usually mild and temporary
Face & tongue weakness is on opposite side of lesion
Phonation:
- Harsh vocal quality
- Articulation
- Imprecise consonants
- Slow rate of speech
- Associated disorders:
- Trauma
- Stroke
Spastic Dysarthria
Site of lesion – Bilateral UMN damage
Phonation:
- Monopitch
- Low pitch
- Reduced stress
- Harsh vocal quality’ “strained-strangled”
- Monoloudness
- Articulation
- Imprecise consonants
- Slow rate of speech
- Effortful
- Jerky movements
Resonance:
Hypernasality
Associated diseases/disorders:
- Bilateral damage to UMNs
- Stroke
- Trauma
- Degenerative diseases
Ataxic Dysarthria
Site of lesion – Cerebellum
Articulation:
- Irregular articulatory breakdowns
- Phonation
- Inappropriate loudness
- Poor pitch control
- Drunken speech (Duffy, 2005)
Associated Diseases/Disorders:
- Cerebral palsy
- Degenerative diseases
- Friedrich’s ataxia
- Stroke
- Tumor
- Trauma
- Alcohol abuse
- Drug toxicity
Hyperkinetic Dysarthria
Site of lesion – basal ganglia
Reduced inhibitory control; results in hyperkinetic (too much) movements
Site of lesion – Cerebellum
Reduced coordination, timing, and rate of movements
Speech characteristics are variable
- Articulation
- Imprecise consonants
- Prolonged speech sounds or long pauses
Phonation:
- Harsh vocal quality
- Excessive loudness
- Monopitch
- Resonance
- Hypernasality
- Associated disorders/diseases:
- Huntington’s disease
- Dystonias
Movement disorders associated with hyperkinetic dysarthria
Tremor
- Resting
- Intention
Tics – rapid, repetitive, stereotyped, involuntary movements
-Can be suppressed for short periods of time
Can be movement (e.g., jumping or hitting) or vocal (e.g., screeching or barking)
Chorea – quick, random, involuntary writhing movements
- Can be anywhere on the body
- Interfere with voluntary movements
Dystonia – random involuntary movements
- Interfere with voluntary movements
- Movements are slow, sustained, and writhing
Hypokinetic Dysarthria
Site of lesion – basal ganglia
Associated disease:
Parkinson’s disease
Phonation:
- Reduced loudness
- Monopitch
- Hoarse voice
- Breathy voice
- Articulation
- Imprecise consonants
- Fast rate of speech- short rushes of speech
Hypokinetic Dyarthria Movement Disorders:
Bradykinesia – difficulty and/or slowness in initiating movements (including speech)
Akinesia – reduced movement (e.g., eye blinking, speech, head, and/or swallowing)
Microagraphia – small handwriting
Resting tremor – pill rolling and other parts of body
Mixed Dysarthria
Site of lesion – Damage to two or more divisions of the nervous system
- This type of dysarthria is relatively common
- Affects multiple components of the motor system for speech
- Results in a combination of two or more types of dysarthria
Associated Diseases/Disorders:
-Amyotrophic lateral sclerosis (ALS)- affects UMNs and LMNs
Can present with spastic-flaccid dysarthria
-Multiple sclerosis – diffuse demyelization
Can present with spastic, ataxic, or mixed dysarthria
Cerebral Palsy
3 major types of CP
Spastic CP – most common motor impairments in CP
-Associated with low birth weight, reduced oxygen and reduced blood flow in premature infants
4 profiles
Spastic hemiplegia
arm and leg on one side have weakness
Mild dysarthria
Spastic paraplegia
(rare)- weakness of both legs
No dysarthria
Spastic diplegia
weakness of all 4 extremities (legs weakest)
Respiratory muscles may be compromised
Spastic quadriplegia
- equal weakness in all 4 extremities
May affect respiratory, laryngeal, articulatory, and palatopharyngeal muscles
Children with bilateral corticobulbar damage
Spastic dysarthria (diplegia or quadriplegia)
Dyskinetic CP
- Associated with mother-child incompatible blood types
Characteristics:
Respiratory issues- result in pitch and loudness problems
Laryngeal dysfunction- difficulty closing vocal folds
Strained vocal quality, monopitch, hypernasality, and imprecise consonants
Ataxia CP
least common type of CP
Damage to cerebellum or cerebellar controls
Ataxic dysarthria
Mixed ataxic-spastic
Tracheostomy & Ventilation
Tracheostomy – an alternative means of respiration
A tube is placed in the larynx which allows the individual to breath (ASHA, n.d.)
A tracheostomy can be temporary or long-term
Reasons for a tracheostomy include damage, obstruction, or dysfunction of larynx such as laryngectomy, tracheomalacia, & laryngeal injury (John Hopkins Medicine, n.d.)
Ventilator – a machine that provides the gases needed for respiration
The ventilator is attached to the tracheostomy
Valves can be placed on a tracheostomy to allow the individual to speak (ASHA, n.d.)
Valves allow air to pass through the vocal folds and larynx
As long as a ventilator patient has a tracheostomy with a valve, they can speak (ASHA, n.d.)
Speech occurs on the expiratory cycle of the machine
Motor/Speech Disorder Assessment
Purpose is to assess:
Phonation, respiration, resonance, and articulation
Impact of motor speech disorder on quality of life
Differential diagnosis
Apraxia vs. dysarthria
Apraxia vs. aphasia
Dysarthria vs. aphasia
Water Glass Manometer
used to measure respiratory pressure for speech
Drinking glass filled with 12 cm of water
Straw is paper clipped to glass
Patient is asked to blow bubbles in the water
Must be able to sustain bubbles for 5 seconds with
straw at a given depth
Key Elemetrics Visi-Pitch
measures acoustic properties of voice signal including:
fundamental frequency (pitch) intensity (loudness) Hz and dB measurements
Videofluoroscopy
used to assess velopharynx (resonance)
Requires SLP and radiologist to interpret results
Apraxia Treatment
Goals: “facilitating the efficiency, effectiveness, and naturalness of communication by
Improving speech production and intelligibility” (ASHA, 2007)
When necessary, introducing augmentative-alternative communication (AAC) (ASHA, 2007)
Restorative treatment – re-establish motor plans for speech
- Typically drill based activities
- Activities are hierarchically structured
- Require adequate auditory comprehension and self-monitoring abilities
Compensatory treatment – compensate for persistent speech deficits
-AAC
Dysarthria Treatment
Treatment plans will be based on many factors including:
- Testing/assessment results
- Prognosis
- Communication environments and partners
- Health status
EARLY INTERVENTION IS KEY – for both children and adults
Medical treatment
- Pharmacology
- Surgery
Prosthetics
- Palatal lift
- AAC
Restorative treatments
- Drill – systematic and repetitive practice
- Feedback
- Self-monitor
Subsystems approach – improve the impaired subsystem
- Respiration
- Phonation
- Articulation
- Resonance
