ICCD
2016
ICCD
Iowa Conference
on Communicative
Disorders
Cedar Falls, Iowa
[DIFFERENTIAL DIAGNOSIS OF
MOTOR SPEECH DISORDERS]
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
Motor Speech Disorders
The evolution of a classification system


Prior to the classification system first introduced by Darley, Aronson, & Brown
(1969), the dysarthrias were considered a single diagnosis.
 The implication was that this diagnosis had homogeneous features.
 Distinctions were made between dysarthria and aphasia, even dysarthria
and apraxia of speech.
Parallels
 Autism
 No longer really considered a unitary diagnosis
 Autism spectrum
•
Further definition
 Asberger’s Syndrome
Differential diagnosis


Evolution of a discipline
 A need to better understand and define clinical populations.
 Evaluation
 More accurate diagnosis
 Treatment
 Guide our treatment decisions
Darley, Aronson, & Brown
 Pivotal articles (1969)
 “Motor Speech Disorders” text (1975)
 Defined and identified the dysarthrias
 Initial sample = 212 patients
 Lesion site
 Perceptual characteristics
 Motor characteristics
Benefits & Drawbacks


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Assists with confirmation of lesion site
 Can rule out other potential diagnoses
Clinical “shorthand”
 Similar to aphasia syndromes
Guides treatment decisions
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 2
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016

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Understanding the underlying pathology results in selecting the appropriate
treatment
Reliability has been questioned
Corresponding lesion data
 Clinical knowledge
 Not confirmed empirically
Take home message…



Clinically useful
 Evolution continues
Our understanding of neuropathology will never be static
 New discoveries
 New procedures
For now, the system is a useful one that will continue to be refined
 Hyperkinetic
 Myriad of movement disorders
The Dysarthrias

“A collective name for a group of neurologic speech disorders resulting from
abnormalities in the strength, speed, range, steadiness, tone, or accuracy of
movements required for control of the respiratory, phonatory, resonatory,
articulatory, and prosodic aspects of speech production. The responsible
pathophysiologic disturbances are due to central or peripheral nervous system
abnormalities and most often reflect weakness; spasticity; incoordination;
involuntary movements; or excessive, reduced or variable muscle tone.”
(Duffy, 2013 p. 4)
Prevalence of MSD

Based on a sample > 14, 000 people referred for a speech/language evaluation at
Mayo Clinic from 1993-2008
 Other neurologic speech disorders - 0.4%
 Apraxia of Speech – 3.9%
 Nonaphasic cognitive-communication disorders – 16.8 %
 Aphasia – 25.8%
 Dysarthria – 53%
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 3
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
Definition revisited:
Key features of the dysarthrias
Neurologic basis
Disorder of movement
Categorized based on
Lesion
Physical characteristics (OME findings)
Speech characteristics
DYSARTHRIA
Lesion
Physical signs
Speech
FLACCID
SPASTIC
ATAXIC
HYPOKINETIC
HYPERKINETIC
MIXED
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 4
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
Flaccid Dysarthria
 Results from injury/damage to cranial and/or spinal nerves
Final common pathway
Lower motor neuron
 Reflexive, automatic, and voluntary activities are ALL affected when the lesion resides in
the FCP.
Can impact all subsystems of speech
 Primary characteristics can be traced to weakness
 Which of the Cranial and/or spinal nerves might be implicated?
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•
Etiologies
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Surgical
Nonsurgical
Neuropathies
Tumor/Neoplasm
Myasthenia gravis
Degenerative
Vascular
Anatomic malformation
Demyelinating
Other
Lesion analysis
• Trigeminal

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Innervation properties
Three branches (sensory)
Motor component
• Signs
Sensory loss
Jaw deviation (unilateral)
 Jaw may hang open (bilateral)
• How do you test?
• Speech signs
 Imprecision in connected speech
 Most affected with bilateral lesions

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• Facial
 Innervation properties
Sensory
 Motor
 Which would be most devastating to speech?
Signs
 Facial droop
 Drooling (possibly)
 Pocketing
Testing

•
•
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 5
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
• Speech signs
 Imprecision in connected speech


Related to facial weakness
What sounds would be most affected?
• Glossopharyngeal
 Innervation properties
Sensory
 Motor
 Signs
 Testing
 Speech signs

• Vagus
 Innervation properties
Sensory
 Motor
 Signs
 Velar signs
 Testing
 Speech signs
 Phonation
 Respiration
 Resonance

• Spinal Accessory
 Innervation properties
Motor
 Signs
 Shoulder weakness
 Testing
 Speech signs

• Hypoglossal
 Innervation properties
Motor
 Signs
 Tongue deviation
 Atrophy
 Testing
 Speech signs
 Imprecision with articulation
 Compensation with the mandible

• Spinal nerve lesions
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 6
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
 Damage to spinal nerves C-1 through C-5
 Primary damage to respiration

How does that interfere with speech?
 Signs
Rapid/shallow breathing
Exaggerated thoracic expansion
 Flaccid dysarthria related to isolated damage to spinal nerve lesions is rare


Primary Characteristics
• Weakness
• Hypotonia and reduced reflexes
• Fasciculations and fibrillations
Darley, Aronson & Brown (1969)
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Hypernasality
Articulatory Imprecision
Breathiness
Monopitch
VPI
Audible inspiration
Harsh vocal quality
Short phrases
Monoloudness
***********************************************************************************
Spastic Dysarthria
 Secondary to damage of the direct and indirect pathways of the CNS (UMN system)
 Direct pathway
 Pyramidal tract
 Corticobulbar tracts
 Interacts with cranial nerves
 Corticospinal tracts
 Interacts with spinal nerves
 Facilitatory action
 Leads to skilled discrete movements
 Indirect pathway
 Extramyramidal
 Regulates reflexes, maintains posture, tone
 Inhibatory nature
Clinical Characteristics
 Difficulty with fine, discrete movements
 Initially decreased tone
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 7
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016

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Weakness
Develops into increased tone, spasticity
 Those muscles utilized in fine movements most affected
Decreased reflexes initially, then more pronounced
Babinski sign
Oral motor reflexes
 Suck
 Snout
 Jaw jerk
Etiologies
 Vascular
 Brainstem stroke
 Bilateral effects
 Cerebral stroke can’t have the same impact, unless there is previous damage, or
perhaps midline shift/compression from a hemorrhagic stroke
 Lacunar infarcts
 Multi-infarct dementia
 Not a common problem with DAT
 Inflammatory
 Leukoencephalitis
 Degenerative disease
 Primary lateral sclerosis
 Traumatic Brain Injury
 Multiple Sclerosis
 Neoplasm
Oral Mechanism
 Dysphagia
 Drooling
 Pseudobulbar affect
 Normal jaw strength
 Facial movements may be slow then move into excess/extreme
 Hyperactive reflexes
Speech Characteristics
 Impairments noticed most by looking at muscle movement rather than isolated muscles
 •« speed
 •«range
 •«force
 •ªmuscle tone
Darley, Aronson, & Brown (1969a)
 Imprecise artic
 Monopitch
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 8
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
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•« stress
Harshness
Monoloudness
Low pitch
Slow rate
Hypernasality
Strained-strangled quality
Short phrases
Distorted vowels
Pitch breaks
Breathy quality
Excess and equal stress
***********************************************************************************
Ataxic Dysarthria
 Cerebellum
 Two cerebellar hemispheres
 Vermis
 Ipsilateral contribution
 Unlike the cerebral hemispheres which have contralateral contributions
 With median lesions, effects may be bilateral
How does the “circuit” function?
 The “circuit”
 Notice of movement-cerebral hemispheres
 Monitors the movement via feedback from the muscles/joints that conduct the
movement.
 Regulates movement in an ongoing fashion based on both ends of this circuit.
Clinical Characteristics
 Ataxic dysarthria typically manifests with diffuse cerebellar damage

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
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 Any signs/symptoms from unilateral lesions tend to improve rapidly
Disordered gait
Truncal instability, titubation
Rotated head postures
Occular motor abnormalities
Ataxic dysarthria
Etiologies
 Degenerative Diseases
 Hereditary Ataxias
 Multiple Sclerosis
 Paroxysmal Ataxic Dysarthria
 Vascular Disorders
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 9
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
 Aneurysms
 AVMs
 Occlusion in the vertebrobasilar system
 Neoplasm
 Trauma
 Toxic/metabolic conditions
 Alcoholic cerebellar degeneration
 Severe malnutrition
 Vitamin deficiencies
 Pharmacological
 Antiseizure drugs
 Lithium
 Valium
 Hypothyroidism
 Normal Pressure Hydrocephalus
Oral Mechanism
 Most aspects of the OME can be entirely normal
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Size
Strength
Symmetry
Face, jaw, tongue, palate
Rest, and during sustained postures
Gag
Reflexive swallow
OME abnormalities
 Irregular AMRs
 Observe the regularity of movement of the tongue, lips, and jaw
 AMRs and connected speech
 Systemic problem
 Affects the entire system rather than isolated impairment from muscles/muscle
groups
Speech
 Imprecision with artic
 Irregular artic breakdown
 Distorted vowels
 Excess and/or equal stress
 Prolonged phonemes/pauses
 Slow rate
 Harshness
 Monopitch
 Monoloudness
 Reduced/irregular breathgroups
Darley, Aronson, & Brown 1969
 Artic imprecision
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 10
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
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Excess/equal stress
Irregular artic breakdowns
Distorted vowels
Harsh quality
Prolonged phonemes
Prolonged intervals
Monopitch
Monoloudness
Slow rate
Loudness variations
Voice tremor
***********************************************************************************
Hypokinetic Dysarthria
• Pathology of the basal ganglia control circuit
– Rigidity
– Reduced force/range
• Decreased mobility a/o range lead to the name “hypokinetic”
• The only dysarthria which has
“rapid” speech rate as one of the perceptual characteristics.
• Depletion or reduction of the neurotransmitter, dopamine.
• Parkinson’s disease that best reflects hypokinetic dysarthria.
• Basal Ganglia Control Circuit
– Functions
• Regulate muscle tone
• Movements that support goal directed activity
• Postural adjustments
• Adjust movements to the environment
• Assists in learning new movements
• Damage results in reduced movement a/o a failure to inhibit involuntary movement
• Hypokinetic dysarthria most reflects reduced movement
Clinical Characteristics
•
Resting tremor
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 11
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
•
•
–
–
–
–
4-7 Hz
Limbs
Pill-rolling
Jaw, lips, and tongue
Rigidity
– Resistance to passive stretch
– Decreased movement
Bradykinesia/Akinesia
– Slow movement
– Freezing
– Shuffling gait
– Micrographia
– Masked facies
– Reduction in:
• Arm movement while walking
• Gestures
• Blinking
• Head movement
• Swallowing frequency
• Loss of postural reflexes
– Reduced “righting” response
– Stooped posture
– Difficulty initiating movment
• While lying down
• Sitting to standing
Etiologies
• Damage to the basal ganglia
– Degenerative
– Vascular
– Traumatic
– Inflammatory
– Neoplastic
– Toxic
– Metabolic diseases
Oral Mechanism
• Immediate revealing features
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 12
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
– Masked facies
• Flat affect
– Respiratory signs
– Infrequent swallowing
• May result in drooling
– Size, strength, and symmetry may be normal
– AMRs may be slowly initiated a/o rapid and restricted in range
Speech Characteristics
• Monopitch
• Monoloudness
– Reduced intensity
– Breathy quality
• Reduced stress
• Short phrases
• Variable rate
• Short rushes of speech
• Imprecise consonants
***********************************************************************************
Hyperkinetic Dysarthria
• Another dysarthria type that manifests secondary to damage to the basal ganglia control
circuit
• May effect all or isolated speech subsystems.
• Involuntary movement is the hallmark feature
– Rhythmic
– Irregular
– Fast
– slow
Abnormal
• What constitutes abnormal?
• Involuntary movements when steadiness is expected
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 13
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
• Hyper-in this case does not mean fast
– Excessive, extra
• Many forms
• Classified based on speed and periodicity
Classification
• Dyskinesia
• Myoclonus
• Tics
• Chorea
• Ballism
• Athetosis
• Dystonia
• Spasm
• Tremor
Etiologies
• Degenerative
• Vascular
• Traumatic
• Inflammatory
• Toxic
• Metabolic disease
***********************************************************************************
Mixed Dysarthrias
• Mixed dysarthrias
– Combination of dysarthrias
• Two or more
• Diffuse damage
• Etiologies
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 14
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
– Degenerative
• ALS
• MS
• PSP
– Toxic metabolic
• Wilson’s disease
• Hepatocerebral degeneration
• Hypoxic encephalopathy
– Vascular Disorders
– Trauma
– Neoplasm
– Infectious diseases
***********************************************************************************
Apraxia of Speech
“A neurologic speech disorder that reflexts an impaired capacity to plan or program sensorimotor commands necessary for directing movements that result in honetically and prosodically
normal speech. It can occur in the absence of physiologic disturbances associated with the
dysarthrias and in the agsence of disturbance in any component of language.”
(Duffy, 2013, p. 4)
• Apraxia of speech is secondary to a disturbance of the motor programming system.
– Central impairment
– Can occur without muscle impairment
– Normal function is apparent
• High variability
• The motor speech programmer executes the motor movements/sequences necessary to
convey language
– Speech ‘vs’ Language
• Primarily left hemisphere lesions
– Motor speech area
– Brocca’s area
– Supplementary motor cortex
– Insula
• Variability in lesion locations
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 15
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
– Dronkers, 1993
Etiologies
• AOS is secondary to primarily focal lesions
– vascular
– Tumors
– Focal/discrete trauma
• Surgical
• Other
• Degenerative conditions
– Occasionally have focal effects
Clinical Characteristics
• May exhibit right sided weakness
– May also have sensory deficits
• Hyperactive reflexes
• Limb apraxia
• Concomitant aphasia
– Brocca’s type
• Can exist in a “pure” form
– Few documented cases
Assessment findings
• Oral mechanism
– May have rt. weakness
• May result in dysarthria that is not the same as AOS
– Nonverbal oral motor apraxia
• Difficulty performing oral tasks.
– Sequential AMRs
• Most sensitive task to the effects of AOS.
Specific Speech Characteristics
• Slow rate
• Prolonged consonants/vowels
• Many pauses
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 16
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
– Inter/intrasegmental
• Disruptions in prosody
• Equal stress
• Decreased pitch/intonation contours
• False starts
• Effortful/laborious speech
• Repetitions
***********************************************************************************
Factors that influence speech production
Injurious Falls
Walking
One-third of Americans aged 65+ fall each year.
Every 14 seconds, an older adult is treated in the E.R. for a fall, every 29 minutes an older adult
dies after a fall.
Annually, falls result in more than 2.4 million injuries in emergency departments, resulting in
over 772,000 hospitalizations and over 21,700 deaths.
In 2012, the costs related to falls was over $36 billion, with an expectation to reach over 59
billion annually by 2020.
Aging
Affects gait patterns
Change in skeletal structure
Reduced muscle mass/strength
Results in a higher incidence of neuropathology.
Often with deleterious cognitive and motor effects.
Increasing incidence of falls
Fear of falling
Multitasking
Bombarded today by competing stimuli
Cell phones
Talking or texting
Music
Environment
Walking while talking
Sharing tasks may become more difficult when systems become compromised.
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 17
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
Statement of the Problem

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Injurious falls are a major medical concern.
Individuals with neurologic compromise may be at a greater risk.
There are known factors that contribute to fall risk.



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Physical decline
Cognitive decline
Pharmacological effects
Environmental factors
What other factors may be influential?

Cognitive load…
GAITRite™ System

Analysis of gait conducted using the GAITRite™ System



14’ portable carpet
16,128 embedded sensors to capture footfalls instantly
Measures include temporal and spatial parameters
Procedures
 Each of the groups completed the following:
 Montreal Cognitive Assessment
 Beck Depression Index
 Gait Measures

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

Baseline (walking, no talking)
Low load (counting by ones)
Medium load (subtracting by 3s)

Originating number varied/attempt
High load (alpha-numeric sequence)

D-7, E-8, F-9…
 Gait conditions were counterbalanced to account for order effect.
 Each walk was completed twice to control for learning

The average was used for analysis.
Dependent measures

Functional ambulation profile (FAP)
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 18
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016

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Ratio of step length to leg length to step time; FAP score is derived from a formula
that includes several critical gait parameters found to be highly related to fall risk.
(Nelson et. al, 1999)
Velocity

Centimeters/second
Stride length

Centimeters
Double support time

The percentage of time per ambulation cycle with both feet on the ground.
Parkinson and Healthy Elderly
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Twenty six participants with Parkinson Disease: Peak medication time

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Age: Mean = 67.44 (41-91)
Hoehn & Yahr Stage:
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22-Stage 2, 3-Stage 3, 1-Stage 4
Thirteen healthy elderly participants
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Age: Mean – 68.07
Matched for education level
No significant differences across groups

Stride length or Velocity

Data were collapsed and a condition effect was revealed Baseline > High load
A significant difference and interaction was revealed for Double Support


The healthy adult group significantly increased their Double Support time
The group with PD did not
High vs. Low Medication State
We recruited the same twenty six participants several months later. We asked that they be
within 30 minutes of their next medication administration. The same procedures were followed,
and we added the Functional Ambulation Profile (FAP) score as a predictor of fall risk.

No differences between conditions or High/Low medication states
 Step velocity
 Step length
 Double support
 FAP
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 19
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016

Dopaminergic replacement medication did not alleviate the effect of cognitive load.
 These results were shared at the World Congress on Parkinson Disease in Paris
2009
Current Study

A double blind, randomized control study to investigate the effects of cognitive enhancing
medication on performance in individuals with Parkinson disease.


Participants were randomly assigned to a drug (Rasagiline vs. Placebo).

After 30 days, participants received an increased dose
 Participants receiving Rasagiline were given a higher dosage for the next 30 days.
 Participants receiving the placebo received additional placebo tablets.

Prior to taking the drug, baseline measures were collected on all experimental tasks
(Pre-treatment).
 Gait
 Additional measures
After 60 days, final data collection occurred (Post-treatment).
 Gait
 Additional measures
Walking while talking
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Individuals with neurological compromise are at an increased risk for falls during the
multitask of talking while walking.
Automatic speech doesn’t carry as great a risk.
Increased cognitive load will have deleterious effects especially in high fall risk conditions

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Low light
Descending stairs
Giving directions
Mental calculations
Tracking conditions
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Obstacles
Environmental variations
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 20
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
Cranial Nerve Information Sheet
Cranial Nerve
I – Olfactory
Type
Function
Sensory
Smell
II – Optic
Sensory
Vision
III - Oculomotor
Motor
Eye movement
IV - Trochlear
Motor
Eye movement (superior oblique)
Facial sensation – 3 branches
Sensory
V - Trigeminal
VI - Abducens

Opthalamic
 Maxillary
 Mandibular
Anterior tongue sensation
Motor
Muscles of mastication
Motor
Eye Movement - lateral rectus
Sensory
Taste - anterior 2/3 tongue
Motor
Facial expression
VII - Facial
Hearing
VIII - Vestibulocochlear
Sensory
Balance
Sensory
Pharyngeal sensation
Motor
Pharyngeal muscles
Sensory
Pharynx, larynx, esophagus
Motor
Muscles of palate, pharynx, and
larynx
Motor
Shoulder, head movement
IX - Glossopharyngeal
X - Vagus
XI- Spinal Accessory
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 21
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
XII - Hypoglossal
Motor
Tongue movement
For the purpose of screening, the functions listed above are the primary functions of the cranial nerves.
This is not meant to serve as an exhaustive list of cranial nerve functions.
© Stierwalt, J.A.G., (2003) Cranial Nerve Information Sheet
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Page 22
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
Cranial Nerve Screening
Cranial Nerve
Function
Screening Task
I – Olfactory
Sensory - Smell
odors
II – Optic
Sensory - Vision
vision chart/acuity
III- Oculomotor
Motor – Eye movement
"follow the moving finger"
IV - Trochlear
Motor – Eye movement
(superior oblique)
look at the nose
V - Trigeminal
Sensory - facial
sensation/anterior tongue
Have the individual close
their eyes: touch the face
Motor - muscles of
mastication
Palpate muscles that clench
the teeth
VI - Abducens
Motor - lateral rectus
look to the side
VII - Facial
Sensory - taste
sweet, sour, bitter, salt
Motor - facial expression
smile, raise the eyebrows
Sensory - hearing
a tuning fork
balance
look for vertigo
Sensory - pharynx
sensation
gag reflex
Motor – pharyngeal muscles
gag reflex
Sensory –pharynx, larynx,
esophagus
Check phonation
VIII Vestibulocochlear
IX - Glossopharyngeal
X - Vagus
Julie A.G. Stierwalt, Ph.D.
Mayo Clinic
Assess vocal quality
Page 23
Stierwalt: Differential Diagnosis of Motor Speech Disorders – April 8, 2016
Motor - muscles of palate,
pharynx, and larynx
XI- Spinal Accessory
Motor – Shoulder, head
movement
shoulder shrug and/or
turning the head to
resistance
XII - Hypoglossal
Motor - tongue movement
Assess tongue movement
© 2003 Julie A.G. Stierwalt, Ph.D.
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