Unit 1 Flashcards
What is apraxia of speech?
neurologic disorder that reflects an impaired ability to plan or program movements for speech
What is dysarthria?
The collective name for a group of neurologic speech disorders that reflect abnormalities in strength, speed, range, steadiness, tone, or accuracy of speech movements
How are developmental motor speech disorders characterized?
Onset of the disorder is prior to language (before age 2)
What is an example of a developmental motor speech disorder?
CP- often caused by a stroke in utero or anoxia/hypoxia during birth
An acquired motor speech disorder is _______
after the onset of language
The central nervous system is comprised of the __________ and the ______________.
Brain and spinal cord
The peripheral nervous system is composed of…?
cranial, spinal, and the peripheral autonomic nerves
How many cranial nerves are in the PNS?
12
How many spinal nerves are in the PNS?
31
What is the purpose of peripheral autonomic nerves?
Carry sensory information from the peripheral organs to the brain
What is the purpose of cranial nerves?
The cranial nerves project from parts of the CNS within the skull and innervate many organs and muscles of the head, neck, thorax, and abdomen
What is the purpose of spinal nerves
Spinal nerves branch from the spinal chord and innervate most of the other muscles of the body: chest, arms, and legs
What protects the brain, brainstem, and cerebellum?
Skull
What supports and protects the spinal cord?
The vertebrae
How many total vertebrae are there?
33
What are the 3 layers of meninges?
Dura mater, arachnoid, and pia mater
What are the 3 spaces between the meninges?
Epidural space, subdural space, subarachnoid space
Where is the epidural space?
Between the skull and the dura
Where is the subdural space?
Below the dura mater
Where is the subarachnoid space?
beneath the the arachnoid
Which space is filled with cerebral spinal fluid?
The subarachnoid space
Diseases capable of producing MSDs that involve the meninges and spaces stem from…?
infection, venous vascular disorders, hydrocephalus, or trauma w/ hemorrhage and edema
What are the 3 parts of a neuron (nerve cell)?
cell body, dendrites, and axon
Which part of the neuron is covered with myelin?
Axon
What are tracts?
Tracts are bundles of axons following similar path in the CNS
Grey matter consists of…?
Neurons and glial cells
What matter is composed of…?
myelinated axons
What occurs between the axon and another dendrite?
a synapse
3 different etiologies of neuronal loss
- Ischemia
- motor neuron diseases
- demyelinating diseases
What is ischemia?
A deprivation of oxygen- occurs during a stroke
What are motor neuron diseases?
Involve the degeneration of motor neurons: e.g., ALS
What are demyelinating diseases?
The myelin on the axons is attacked/broken down (e.g., MS)
Apraxia results from damage to the _________________.
The frontal lobe (Broca’s area, premotor cortex, supplementary motor area, primary motor cortex)
Damage to the primary motor cortex causes…
weakness or paraylsis to muscle groups on the contralateral side of the body
What will happen if dopamine levels are lowered?
muscular rigidity, tremor, gait, disturbances and difficulty initiating movement
What is a track?
A bundle of neurons that travel together for a specific function in the CNS
What is a nerve?
A bundle of neurons that travel together for a specific function in the PNS
5 steps in the basic expressive communication model
- Cognitve/conceptualization level
- Linguistic planning
- motor planning/programming
- speech production/performance
- feedback
What are three types of motor acts?
- Autonomic motor functions (e.g., heart beat)
- Reflexes, automatic responses to external stimuli (startle reflex)
- Voluntary motor acts
What type of motor speech disorder results in damage to planning/programming?
APRAXIA
Where is the SOL for acquired apraxia?
Broca’s area or surrounding area in the the left frontal lobe
Acquired apraxia often co-occurs w/ _________
aphasia
What are speech characteristics of apraxia?
Groping, better in short, automatic speech
What is childhood apraxia of speech?
A motor planning deficit, no lesion, often difficulty pregnancy/birth
What are speech characteristics of CAS?
groping, better short speech, early developing phonemes are in error
Where are Upper motor neurons?
STAY IN the CNS
What are upper motor neurons?
The neurons originate in the cerebral cortex and the neuron’s axons descend as part of the corticobulbar or corticospinal tracts to the cranial nerve nuclei in the brainstem or to the ventral horn of the spinal cord
What are the upper motor neurons part of?
Pyramidal and Extrapyramidal pathways
Where do upper motor neurons end?
at the cranial nerves and control circuits
What is the pyramidal activation pathway?
Long axons of either the corticospinal or corticobulbar tract with monosynaptic connections
Where does the synapse occur in the corticospinal tract?
spinal nerves
Where does the synapse occur in the corticobulbar tract?
cranial nerves at different levels of the brain stem
Why is the corticospinal tract important for speech?
Plays a role in respiration
Why is the corticobulbar tract important for speech production?
Controls all voluntary muscles for speech- controls what to move when
Each hemisphere’s uppon motor neuron pathway innervates ___________
Lower motor neurons on the opposite side of the body
Most of the upper motor neuron innervation of the cranial nerves is primarily __________.
BILATERAL
Which parts are not innervated bilaterally?
Lower face and tongue
What will happen if there is unilateral upper motor neuron damage?
Reduction of skilled movements and possible weakness on the opposite side of the body
What results from unilateral UMN damage?
dysarthria
What are control circuits?
A circuit that loops infomration in various structures and sends information back to the cortex
What are 2 control circuits?
- Basal ganglia control circuit
2. cerebellar control circuit
Lower motor neurons are also called what?
Cranial nerves
What is the purpose of the cerebellar control circuit?
Uses feedback from periphery to give information back to the cortex for smooth, coordinated movement
What does the cerebellar control circuit coordinate?
fine motor movements, balance, regulates rate, range, direction, and force of movements
Damage to the cerebellar control circuit results in what?
Ataxic dysarthria “drunken” movements
Where does the indirect activation pathway originate and end?
originates- motor areas of the cortex
ends- cranial and spinal nerves
Indirect pathways are __________
Polysynaptic
What does the indirect activation system regulate?
Muscle tone, posture, suppresses unnecessary movements, supportive of voluntary movements, and reflex activities
What does the rubrospinal tract control?
muscle tone for posture
What does the reticulospinal tract control?
autonomic functions
What does the tectospinal tract control?
neck muscles
What does the vestibulospinal tract control?
balance
What does it mean when it says that extrapyramidal tract is inhibitory?
It stops unwanted, extra movements, stops extra reflexes, stops contractions
Damage to the indirect pathway can lead to:
Increased muscle tone, spasticity, and hyperactive gag reflex
What is the etiology of spastic dysarthria?
bilateral damage to direct and indirect pathway
Motor neurons that do not leave the CNS are called…
Upper motor neurons
Motor neurons that leave the CNS are called…
Lower motor neurons
What does the facial nerve innervate?
Upper and lower face
What does the hypoglossal nerve innervate?
Tongue
What does the vagus nerve innervate
Velum and larynx
What does the trigeminal nerve innervate?
jaw
Describe how information gets to the cranial nerves from the brain
- Corticobulbar tracts travel down and cross at the medulla
- In midbrain, corticobulbar fibers separate from corticospinal nerves
- Corticobulbar tracts synapse w/ cranial nerve nuclei on either side of the brainstem (left or right)
What is the purpose of LMN?
LMNs exit the brainstem and travel into the periphery to innervate the muscles
When do muscles atrophy?
LMN damage
Which cranial nerves receive unilateral innervation?
VII and XII (Facial and hypoglossal)
What motor functions does the trigeminal nerve (V) control?
mastication, jaw closing and lateralization
If there is unilateral LMN damage to the trigeminal nerve, what will be the result?
Weakness or paralysis of the jaw on the same side- the jaw may deviate toward affected side when opened
Bilateral damage to the trigeminal nerve would lead to…?
Difficulty raising/clossing the jaw resulting in significant problems with speech
What are the 2 branches of the facial nerve?
Upper face and lower face
The upper face recieves…
Bilateral UMN innervations
The lower face recieves…
Unilateral (contralateral) UMN innervations
What motor functions does the facial nerve control?
Lips (smiling, frowning), cheeks for plosives, closing eyes, forehead wrinkling, middle ear muscles
The glossopharyngeal CN 9 travels closely to which CN?
CN 10- Facial
What are the 3 branches of the vagus nerve X?
- Pharyngeal branch
- Superior laryngeal branch
- recurrent nerve branch
What does the pharyngeal branch innvervate?
Pharynx and velum
What does the superior laryngeal branch innervate?
Cricothyroid muscle of the larynx
What function of the larynx does the superior laryngeal branch serve?
Stretching the VF- pitch
The recurrent laryngeal nerve branch assists with what function of the larynx?
adduction and abduction
The hypoglossal nerve (CN XII) innervates what?
The tongue muscles
The hypoglossal CN XII receives ____________ innervation.
unilateral
Damage to the cerebellum will result in what?
Poor coordination
Damage to the basal ganglia will result in what?
too much movement, too little movement
What are 4 characteristics of upper motor neuron damage?
- spastic
- no atrophy
- increased reflexes
- no fasciculations
What are 4 characteristics of lower motor neuron damage?
- flaccid
- muscle atrophy
- absent reflexes
- fasciculations often present
3 types of nervous system disease
- focal
- multifocal
- diffuse
What is a focal nervous system disease?
Involves a single circumscribed area or a contiguous group of structures (e.g., left frontal lobe)
What is a multifocal nervous system disease?
involves more than one area or more than one group of structures
What is a diffuse nervous system disease?
involves roughly symmetric portions of the nervous system bilaterally (e.g., dementia)
Acute is…
Within minutes
Subacute…
within days (e.g., infections)
Chronic is…
within months (e.g., tumor)
Transient symptoms are…
When symptoms resolve completely
Improving symptoms are…
when severity is reduced but symptoms are not resolved
Progressive symptoms…
symptoms progress over time or new symptoms develop
Exacerbating-remitting symptoms…
symptoms develop, then resolve or improve, then recur
Stationary symptoms…
remain unchanged for an extended period of time
What are neoplastic diseases?
usually tumors
