FACEFACEWhich cranial nerves supply Which cranial nerves supply

sensory and motor functions of the face and sensory and motor functions of the face and associated structures (e.g. hard palate, teeth and associated structures (e.g. hard palate, teeth and

gums)?gums)?

SensorySensory from face (Think of a from face (Think of a face with teeth bared, and eyes face with teeth bared, and eyes and nares open flared): and nares open flared): Trigeminal nerve (V)Trigeminal nerve (V)• Cutaneous sensations from face Cutaneous sensations from face

(pain, temp., touch): Trigeminal (V)(pain, temp., touch): Trigeminal (V)– Proprioception from face: Facial (VII)Proprioception from face: Facial (VII)

• Touch from cornea of eye and nasal Touch from cornea of eye and nasal mucosa (V, ophthalmic branch)mucosa (V, ophthalmic branch)

• Teeth and gums: Trigeminal (V)Teeth and gums: Trigeminal (V)– Maxillary branch: upper teeth and gums, Maxillary branch: upper teeth and gums,

plus hard palateplus hard palate– Mandibular branch: lower teeth and gums, Mandibular branch: lower teeth and gums,

plus lower jaw and inside of cheekplus lower jaw and inside of cheek

• Skin of external ear and external Skin of external ear and external auditory canal: Vagus (X), with some auditory canal: Vagus (X), with some assistance by V, for tragusassistance by V, for tragus

VV

It is branches of V that are numbed by the dentist when you have dental work

Branching of VBranching of V

• V (Trigeminal): 3 V (Trigeminal): 3 branchesbranches– Ophthalmic: Ophthalmic: SensorySensory– Maxillary: Maxillary: SensorySensory– Mandibular: Mandibular: SensorySensory

(+(+motormotor of of mastication, which mastication, which we’ll study later)we’ll study later)

V

V

Testing Testing SensorySensory of V in of V in faceface

• Sensory of V (trigeminal): Sensory of V (trigeminal): With eyes closed, stroke…With eyes closed, stroke…– above eyebrows (tests above eyebrows (tests

ophthalmic branch)ophthalmic branch)– upper lip (tests maxillary upper lip (tests maxillary

branch)branch)– between lower lip and chin between lower lip and chin

(tests mandibular branch)(tests mandibular branch)

• If you touch the pinna or ear If you touch the pinna or ear canal you’re testing X (vagus). canal you’re testing X (vagus). V innervates only the tragusV innervates only the tragus

It is branches of V that are numbed by the dentist when you have dental work

Fibers cross

Upper face: Mostly contralateral,some ipsilateral

Fibers don’t cross

Lower face: Contralateral only

• Remember: Remember: – Bilateral UMN Bilateral UMN

innervation to the innervation to the upper faceupper face

– Unilateral UMN Unilateral UMN innervation innervation (contralateral) to the (contralateral) to the lower facelower face

– LMNs (facial nerve VII LMNs (facial nerve VII and its branches) and its branches) innervate the whole innervate the whole face on the same side face on the same side as the cranial nerveas the cranial nerve

MotorMotor innervation innervation to muscles of facial to muscles of facial expression: VII expression: VII (facial)(facial)

MotorMotor innervation to innervation to muscles of face: VII (facial)muscles of face: VII (facial)

• Notice how cranial Notice how cranial nerve VII (facial) nerve VII (facial) exits the cranium at exits the cranium at the the internalinternal acoustic acoustic meatus (one of the meatus (one of the foramina in the foramina in the cranium), which is cranium), which is intimately close to intimately close to the inner ear. It the inner ear. It exits here with VIII.exits here with VIII.

Branching of VIIBranching of VII• VII (Facial) VII (Facial)

branchesbranches– SVE to muscles of SVE to muscles of

facial expression facial expression (including (including muscles for tight muscles for tight closure of eye) in closure of eye) in yellowyellow

– GVE to lacrimal GVE to lacrimal glands, nasal glands, nasal mucosa and some mucosa and some salivary glands salivary glands ((redred) )

Note that VII also mediates

proprioception from face receptors (embedded in

muscles)

MotorMotor innervation to certain glands innervation to certain glands near/around face/mouthnear/around face/mouth

• Facial nerve (VII) also mediatesFacial nerve (VII) also mediates– Visceral innervation (in red) to Visceral innervation (in red) to

• lacrimal glands, lacrimal glands,

•nasal mucosa and nasal mucosa and

•some salivary glands: some salivary glands: Submandibular and sublingual Submandibular and sublingual (#2 and #3 below)(#2 and #3 below)

VII

Note that VII also innervates Note that VII also innervates stapedius musclestapedius muscle

• VII: Dampens vibrations of the VII: Dampens vibrations of the ossicles associated with loud noises ossicles associated with loud noises (stapedius muscle) (stapedius muscle)

• V: Dampens vibrations of the ossicles V: Dampens vibrations of the ossicles associated with the noise of chewing associated with the noise of chewing (tensor tympani)(tensor tympani)

FACEFACEClinical ApplicationsClinical Applications

Pathology of motor of face Pathology of motor of face (VII) (VII) • Motor of VIIMotor of VII– Upper motor neuron lesion, e.g. cerebral strokeUpper motor neuron lesion, e.g. cerebral stroke

•Complete involvement below eye, some involvement Complete involvement below eye, some involvement around eye, little difficulty with forehead and frontalis around eye, little difficulty with forehead and frontalis muscle. (Note: Only applies to voluntary movement, muscle. (Note: Only applies to voluntary movement, not emotionally initiated movements.) not emotionally initiated movements.)

– Lower motor neuron lesion: Moebius syndrome, Lower motor neuron lesion: Moebius syndrome, biilateral congenital atrophy of VIIbiilateral congenital atrophy of VII

– LMN lesion: Bell’s palsy, unilateral compression, viral LMN lesion: Bell’s palsy, unilateral compression, viral infect. infect.

•Paralysis of entire side of face ipsilateral to the site of Paralysis of entire side of face ipsilateral to the site of the compression or infectionthe compression or infection

•Problems with eyelid closingProblems with eyelid closing

•Drooping corner mouthDrooping corner mouth

•(Taste on anterior 2/3 of tongue affected)(Taste on anterior 2/3 of tongue affected)

•Poor production of tears, reduced salivationPoor production of tears, reduced salivation

Testing motor of VII in faceTesting motor of VII in face• Motor (voluntary) of VII (See pg. 156 of W&A)Motor (voluntary) of VII (See pg. 156 of W&A)

– Face at rest (look for asymetry)Face at rest (look for asymetry)– Wrinkle forehead and look upWrinkle forehead and look up– Close eyes as tightly as possibleClose eyes as tightly as possible– Smile, pucker, poutSmile, pucker, pout

• Whole side of face affected = _______ lesion on Whole side of face affected = _______ lesion on ipsilateral side, associated with _____________ ipsilateral side, associated with _____________ dysarthriadysarthria

• Lower face affected, with some weakness of Lower face affected, with some weakness of upper face = _________ lesion on contralateral upper face = _________ lesion on contralateral side, associated with ___________________ side, associated with ___________________ dysarthriadysarthria

TONGUETONGUEWhich cranial nerves supply Which cranial nerves supply

sensory and motor functions of the tongue?sensory and motor functions of the tongue?

Tongue, Sensory Tongue, MotorGeneral sensory (touch)

Anterior 2/3 of tongue:V, trigeminal nerve, mandibular branch

Special Sensory (taste)

Anterior 2/3 of tongue:VII, facial nerve

All tongue movement (All four intrinsic and all three extrinsic tongue muscles) XII (Hypoglossal)

General and special sensory (touch and taste)

Posterior 1/3 of tongue: IX, glossopharyngeal nerve

Tongue has sensation of two types (touch and taste) and is also able to move. Each of these functions is filled by different cranial nerves.

General General sensorysensory: Touch on : Touch on tonguetongue• V (Trigeminal), mandibular V (Trigeminal), mandibular

branchbranch– General sensory for General sensory for

anterior 2/3 of tongueanterior 2/3 of tongue

• IX (Glossopharyngeal)IX (Glossopharyngeal)– General sensory for General sensory for

posterior 1/3 of tongue. posterior 1/3 of tongue. Do you remember the other sensory functions of V? (think of face, gums, teeth, hard palate, jaw).

When the mandibular branch of V is damaged or anesthetized, what sensory functions would be affected?

Special Special sensorysensory: Taste on : Taste on tonguetongue• VII (Facial)VII (Facial)

– Special sensory for anterior Special sensory for anterior 2/3 of tongue, in 2/3 of tongue, in greengreen on on diagram to right.diagram to right.

• IX (Glossopharyngeal)IX (Glossopharyngeal)– Special sensory for posterior Special sensory for posterior

1/3 of tongue. 1/3 of tongue.

Remember these women who have VII (facial nerve) involvement? They’ll also have problems with taste on the ____________________ of tongue.

Do you remember the cranial nerve of smell (I)? It works with VII and IX (taste).

Clinical testing of Clinical testing of sensorysensory functions of tonguefunctions of tongue

• Swab dipped in flavored solution Swab dipped in flavored solution • Tests taste (function of special sensory branch of Tests taste (function of special sensory branch of

VII)VII)

• Tests touch (function of mandibular branch, general Tests touch (function of mandibular branch, general sensory, of V)sensory, of V)

Motor Motor functions of tongue, functions of tongue, Hypoglossal (XII)Hypoglossal (XII)

• Motor input to muscles Motor input to muscles thatthat– Change the tongue’s Change the tongue’s

shapeshape

•Shorten, narrow, Shorten, narrow, elongate, flatten elongate, flatten and make concaveand make concave

– Move the tongue Move the tongue through spacethrough space

•Protrude, draw Protrude, draw tongue up and tongue up and back, retract and back, retract and depressdepress

Testing tongue movement (looking Testing tongue movement (looking for injury of c.n. XII, i.e., LMN)for injury of c.n. XII, i.e., LMN)

• ProtrudeProtrude tongue (deviation to side of injured tongue (deviation to side of injured cranial nerve (LMN); protrusion of stronger side cranial nerve (LMN); protrusion of stronger side overcomes weaker)overcomes weaker)– Freely and against resistanceFreely and against resistance

• LateralizeLateralize tongue to corners of mouth or to internal tongue to corners of mouth or to internal cheek (inability to lateralize on side of injured cranial cheek (inability to lateralize on side of injured cranial nerve, e.g. XII damaged on R nerve, e.g. XII damaged on R can’t lateralize to R) can’t lateralize to R)– Freely and against resistanceFreely and against resistance

• Elevate tongue while you hold chin downElevate tongue while you hold chin down

• Look for involuntary movements (facsiculations, Look for involuntary movements (facsiculations, fibrillation) and wasting away (atrophy) of the tonguefibrillation) and wasting away (atrophy) of the tongue– Fasciculations are Fasciculations are smallsmall muscle twitches, which look muscle twitches, which look

like little, moving dimpling of tongue; moving like little, moving dimpling of tongue; moving corrugationscorrugations

– Fibrillation looks like a fast tremorFibrillation looks like a fast tremor

Clinical presentation of Clinical presentation of tongue in different tongue in different dysarthriasdysarthrias• Flaccid dysarthria: Look for atrophy, changes Flaccid dysarthria: Look for atrophy, changes

in functional ability and involuntary movement in functional ability and involuntary movement of tongue as described on previous slideof tongue as described on previous slide

• Spastic dysarthria: Articulation is imprecise Spastic dysarthria: Articulation is imprecise and distorted because muscles are too tightand distorted because muscles are too tight

• Ataxic dysarthria: Articulation is sometimes Ataxic dysarthria: Articulation is sometimes precise, sometimes not, due to discoordinationprecise, sometimes not, due to discoordination

• Hyperkinetic dysarthria: Tongue may move Hyperkinetic dysarthria: Tongue may move involuntarilyinvoluntarily

LOWER JAWLOWER JAWWhich cranial nerves supply Which cranial nerves supply

muscles used for movements of mandible muscles used for movements of mandible (for speaking and eating?)(for speaking and eating?)

Sensory Motor

Muscles of mastication

Trigeminal V(proprioception from jaw)

Trigeminal V, mandibular branch (movement of jaw)

You have to be able to move mandible (lower jaw) for chewing (mastication) and speaking, and sense how jaw is positioned

Jaw movement, V (Trigeminal, Jaw movement, V (Trigeminal, mandibular branch)mandibular branch)

• Motor input to muscles thatMotor input to muscles that– Close and open the jawClose and open the jaw– Move the jaw laterally (grinding Move the jaw laterally (grinding

and lateral movements)and lateral movements)

Pathology of motor VPathology of motor V• Motor of V (trigeminal): Lower motor Motor of V (trigeminal): Lower motor

neuron lesion of mandibular branchneuron lesion of mandibular branch– Flaccid paresis or paralysis of the ipsilateral Flaccid paresis or paralysis of the ipsilateral

muscles of masticationmuscles of mastication– Slight deviation of jaw to the same side as Slight deviation of jaw to the same side as

the damaged LMN the damaged LMN

• Unilateral upper motor neuron disease Unilateral upper motor neuron disease unlikely to affect function, because of unlikely to affect function, because of bilateral innervationbilateral innervation– Transitory or mild paresis (i.e., slight or Transitory or mild paresis (i.e., slight or

partial paralysis)partial paralysis)

Testing motor of V (LMN damage)Testing motor of V (LMN damage)• Motor of V (trigeminal): Mandibular Motor of V (trigeminal): Mandibular

branch branch – Palpate area of masseter as patients bites Palpate area of masseter as patients bites

down as hard as possible, then relaxesdown as hard as possible, then relaxes• Feel for bulk of the muscleFeel for bulk of the muscle

– Look for atrophy of the temporal muscle: Look for atrophy of the temporal muscle: Shrunken area at the temple of the face?Shrunken area at the temple of the face?

– Jaw closing while you hold chin down and Jaw closing while you hold chin down and forehead in placeforehead in place• Ask patient to bite down hard against resistance Ask patient to bite down hard against resistance

of your handof your hand

– Jaw opening with resistance under chinJaw opening with resistance under chin– Ask patient to move jaw side to sideAsk patient to move jaw side to side– Ask client to articulate phonemes that Ask client to articulate phonemes that

require jaw movement (e.g. bilabials)require jaw movement (e.g. bilabials)

SOFT PALATESOFT PALATEWhich cranial nerves supply Which cranial nerves supply

muscles used for movements of soft palate, muscles used for movements of soft palate, used for controlling nasality, and for keeping food out of used for controlling nasality, and for keeping food out of

nasal passages when swallowing?nasal passages when swallowing?

Sensory MotorSoft palate

IX (Glossopharyngeal)

V (Trigeminal), flatten and tenseX (Vagus) most innervation of soft palate

Soft palate has sensation, and is also able to move. Each of these functions is filled by different cranial nerves.

SensorySensory innervation of soft innervation of soft palatepalate• Glossopharyngeal (IX) Mediates Glossopharyngeal (IX) Mediates

sensation fromsensation from– Soft palateSoft palate– Posterior 1/3 of tonguePosterior 1/3 of tongue– Tonsils and faucial pillarsTonsils and faucial pillars– Pharynx (which we’ll see in Pharynx (which we’ll see in

upcoming slides)upcoming slides)

• IX also mediates sensation from IX also mediates sensation from the middle ear (tympanic cavity the middle ear (tympanic cavity and Eustachian tube)and Eustachian tube)

MotorMotor innervation of soft innervation of soft palatepalate• Vagus (X) Vagus (X)

– Provides primary Provides primary innervation to soft palateinnervation to soft palate

• V (Trigeminal)V (Trigeminal)– Partially responsible for Partially responsible for

flattening and tensing of flattening and tensing of soft palatesoft palate

– Opens Eustachian tubeOpens Eustachian tube– (Remember that it also (Remember that it also

innervates jaw muscles)innervates jaw muscles)

Clinical testing of Clinical testing of movement of soft palatemovement of soft palate• Motor (V & X): Soft palate should Motor (V & X): Soft palate should

– raise symmetrically on raise symmetrically on repeated production of /a/.repeated production of /a/.

– Raise sufficiently so that no Raise sufficiently so that no nasality is heard on oral soundsnasality is heard on oral sounds

– Raise completely and Raise completely and symmetrically as part of gag reflex symmetrically as part of gag reflex •Do this test only if speech is Do this test only if speech is

hypernasal and no movement is seen hypernasal and no movement is seen on repeated /a/on repeated /a/

Clinical presentation for Clinical presentation for dysarthria of soft palatedysarthria of soft palate• Flaccid dysarthria: Consistently hypernasal, Flaccid dysarthria: Consistently hypernasal,

because soft palate cannot lift at all, or lifts because soft palate cannot lift at all, or lifts only on one side (see previous slide)only on one side (see previous slide)

• Spastic dysarthria: Consistently hypernasal, Spastic dysarthria: Consistently hypernasal, muscles can’t reach posterior pharynxmuscles can’t reach posterior pharynx

• Ataxic dysarthria: Occasional, inconsistent Ataxic dysarthria: Occasional, inconsistent hypernasality; can’t coordinate timing of hypernasality; can’t coordinate timing of palate liftingpalate lifting

PHARYNXPHARYNXWhich cranial nerves supply Which cranial nerves supply

muscles used for sensation in, and movements of, muscles used for sensation in, and movements of, pharynx, pharynx,

important for swallowing and gag reflex?important for swallowing and gag reflex?

Sensory MotorPharynx

IX (Glossopharyngeal)

IX (Glossopharyngeal) lateral dilation + some elevation

X (Vagus)constrictors

Pharynx has sensation, and is also able to move. Each of these functions is filled by different cranial nerves.

SensorySensory innervation of innervation of pharynxpharynx• Glossopharyngeal (IX) Glossopharyngeal (IX)

Mediates sensation fromMediates sensation from– Soft palateSoft palate– Posterior 1/3 of tonguePosterior 1/3 of tongue– Tonsils and faucial pillarsTonsils and faucial pillars

– PharynxPharynx

Motor Motor innervation of innervation of pharynxpharynx• IX, glossopharyngealIX, glossopharyngeal

– Lateral dilation and some Lateral dilation and some elevation of pharynx via elevation of pharynx via stylopharygeus muscle (#1)stylopharygeus muscle (#1)

•Helps clear pharynxHelps clear pharynx– Visceral motor innervation Visceral motor innervation

of parotid gland (#1 on of parotid gland (#1 on right)right)

• X, vagus, pharyngeal branchX, vagus, pharyngeal branch– Pharyngeal constrictors: Pharyngeal constrictors:

moves bolus of food toward moves bolus of food toward esophagusesophagus• Remember that X also Remember that X also

innervates most muscles of innervates most muscles of soft palatesoft palate

Note: damage to the innervation of the parotid would result in EXCESSIVE salivation

Phases of Phases of swallow swallow require the require the use of both:use of both:• Afferent Afferent

(sensory) neural (sensory) neural pathways from pathways from pharynx pharynx – Stimulation of IX Stimulation of IX

initiates the initiates the swallowswallow

• Efferent (motor) Efferent (motor) neural pathways neural pathways to pharynx to pharynx – X provides motor X provides motor

innervation to the innervation to the pharyngeal pharyngeal constrictors, to constrictors, to move the bolus move the bolus downdown

Testing sensory and motor of Testing sensory and motor of pharynx pharynx • Gag reflex (sensation precedes motor activity)Gag reflex (sensation precedes motor activity)– Sensory portion of reflex Sensory portion of reflex

•Glossopharyngeal (IX)Glossopharyngeal (IX)

– Motor portion of reflex: Gag responseMotor portion of reflex: Gag response•Glossopharyngeal (IX): Elevation and dilation of Glossopharyngeal (IX): Elevation and dilation of

pharynx; lifting of soft palate pharynx; lifting of soft palate

•Vagus (X): Contraction of the pharyngeal Vagus (X): Contraction of the pharyngeal muscles, muscles,

– If no gag response, ask “Did you feel the If no gag response, ask “Did you feel the touch/poke?” If answer is yes, then just touch/poke?” If answer is yes, then just motor portion of gag is involved (X). motor portion of gag is involved (X).

(Think of the last time you had a test for strep ….)

LARYNXLARYNXWhich cranial nerves supply Which cranial nerves supply

muscles used for sensation in, and movements of, muscles used for sensation in, and movements of, larynx, larynx,

important for voicing and important for voicing and for protection of airway when swallowing?for protection of airway when swallowing?

Sensory Motor

Larynx

X (Vagus) X (Vagus)Intrinsic muscles of larynx

V (Trigeminal)VII (Facial)IX (Glossopharyngeal)

Extrinsic muscles of larynx Larynx has sensation, and laryngeal

muscles, intrinsic and extrinsic: Both sensory and motor functions help

us to protect airwayMotor functions help us to produce

voicing

SensorySensory innervation of larynx innervation of larynx• Vagus (X) Mediates Vagus (X) Mediates

sensation from sensation from larynxlarynx– Lets you know when Lets you know when

foreign body has foreign body has entered larynxentered larynx

– Senses pain, e.g. in Senses pain, e.g. in cases of laryngeal cases of laryngeal cancercancer

• X (Vagus)X (Vagus)– Sensory (lets you know when Sensory (lets you know when

foreign body is in larynx) foreign body is in larynx) – motor to intrinsic muscles of motor to intrinsic muscles of

larynx (changes voice)larynx (changes voice)

• Movements of whole larynx to Movements of whole larynx to protect airway:protect airway:– V (trigeminal): assists with superior and V (trigeminal): assists with superior and

anterior movement of larynxanterior movement of larynx– VII (facial) assists with superior and VII (facial) assists with superior and

posterior movement of larynxposterior movement of larynx– IX (glossopharyngeal): assists with IX (glossopharyngeal): assists with

elevation of larynxelevation of larynx

Laryngeal INNERVATION

X

• Laryngeal branches Laryngeal branches of vagus nerve (X)of vagus nerve (X)– Superior Superior

laryngeal laryngeal

•External External branchbranch

– Recurrent Recurrent laryngeal laryngeal

MotorMotor innervation of larynx innervation of larynx

Note X (vagus) Note X (vagus) and its branchesand its branches

• PharyngealPharyngeal

• Laryngeal (descends)Laryngeal (descends)– Superior laryngeal Superior laryngeal

(#1)(#1)

•Internal branchInternal branch

•External branchExternal branch– Recurrent laryngeal Recurrent laryngeal

(#6) (#6) Note how it Note how it descends considerably descends considerably below the larynx, and below the larynx, and then re-ascends.then re-ascends.

Recurrent laryngeal nerve is vulnerable in

heart and thyroid surgeries

Functions of each of the branches of Functions of each of the branches of laryngeal nerve (which itself is a branch of laryngeal nerve (which itself is a branch of X vagus)X vagus)• (Pharyngeal)(Pharyngeal)

• Laryngeal (descends)Laryngeal (descends)– Superior laryngeal (#1)Superior laryngeal (#1)

• Internal branch: Sensory Internal branch: Sensory above true vocal folds, above true vocal folds, including epiglottis and including epiglottis and base of tonguebase of tongue

•External branch: Motor to External branch: Motor to the cricothyroid muscle (for the cricothyroid muscle (for pitch changes)pitch changes)

– Recurrent laryngeal (#6): Recurrent laryngeal (#6):

•Sensory of true vocal folds Sensory of true vocal folds and below; and below;

•motor to most of the motor to most of the intrinsic muscles of the intrinsic muscles of the larynx, except cricothyroidlarynx, except cricothyroid

Recurrent laryngeal nerve is vulnerable in heart and

thyroid surgeries

Note:Note:• Vagus also supplies Vagus also supplies

afferent and efferent afferent and efferent visceral innervation, visceral innervation, e.g.e.g.– HeartHeart– Respiratory systemRespiratory system– Most of digestive Most of digestive

systemsystem

• Afferent innervation Afferent innervation and most efferent and most efferent visceral is not visceral is not appreciated at appreciated at conscious levelconscious level

Pathology at laryngeal levelPathology at laryngeal level• Silent aspiration of food into lungs when sensation is affected Silent aspiration of food into lungs when sensation is affected

– internal branch of superior laryngealinternal branch of superior laryngeal– recurrent laryngeal recurrent laryngeal

Test with modified barium swallowTest with modified barium swallow

• With damage to V, VII, IX, ability to move larynx up and under tongue for protection of With damage to V, VII, IX, ability to move larynx up and under tongue for protection of airway may be affectedairway may be affected

• Dysphonia /aphonia when motor functions of larynx are affected (X), via damage to the Dysphonia /aphonia when motor functions of larynx are affected (X), via damage to the – External branch of superior laryngeal, which will affect ability to change pitchExternal branch of superior laryngeal, which will affect ability to change pitch– Recurrent laryngeal branch of laryngeal of X, which will affect voice quality overallRecurrent laryngeal branch of laryngeal of X, which will affect voice quality overall

Test with laryngoscopy and clinical voice evaluationTest with laryngoscopy and clinical voice evaluation

Clinical presentation of Clinical presentation of dysarthria at the laryngeal dysarthria at the laryngeal levellevel• Flaccid dysarthria: Flaccid dysarthria: Voice becomes breathy, and phrases Voice becomes breathy, and phrases

short, ‘cause folds can’t close properly; food may be short, ‘cause folds can’t close properly; food may be aspirated (because glottis doesn’t close)aspirated (because glottis doesn’t close)

• Spastic dysarthria: Voice becomes harsh, strained-Spastic dysarthria: Voice becomes harsh, strained-strangled, with reduced range of stress and loudness, strangled, with reduced range of stress and loudness, ‘cause vocal muscles are too tight‘cause vocal muscles are too tight

• Ataxic dysarthria: A coarse tremor of the vocal folds; pitch Ataxic dysarthria: A coarse tremor of the vocal folds; pitch goes up and down. Air support is also uncoordinated, so goes up and down. Air support is also uncoordinated, so there is occasional excessive loudnessthere is occasional excessive loudness

• Hypokinetic dysarthria: Monopitch because vocal muscles Hypokinetic dysarthria: Monopitch because vocal muscles cannot initiate larger movements. Diaphragm does not cannot initiate larger movements. Diaphragm does not move fully, so voice is monoloud, with low intensitymove fully, so voice is monoloud, with low intensity

• Hyperkinetic dysarthia: Voice stoppages and breaks; Hyperkinetic dysarthia: Voice stoppages and breaks; excessive loudness variation from involuntary diaphragm excessive loudness variation from involuntary diaphragm mvmt.)mvmt.)

MUSCLES OF HEAD TURNING MUSCLES OF HEAD TURNING AND SHOULDER SHRUGGINGAND SHOULDER SHRUGGING

Which cranial nerves supply Which cranial nerves supply muscles used for head turning and shoulder shrugging, muscles used for head turning and shoulder shrugging,

important for visual scanning and communication?important for visual scanning and communication?

Sensory MotorHead/shoulders

-- (spinal cord innervates sensory from shoulders and back of head)

XI (Spinal accessory) moves head and shrugs shoulders

We need to turn head both to receive communication effectively and to shake our heads ‘no’

We need to shrug shoulders to communicate, and also to lift arm when communicating via pointing

XI: Accessory, spinal accessory

Connects at the spinal cord (spinal root of XI) and medulla (cranial root of XI)

Note XI (spinal accessory) and its two Note XI (spinal accessory) and its two rootsroots• Cranial root (from Cranial root (from

medulla)medulla)– Joints X (vagus) and is Joints X (vagus) and is

“accessory” to the “accessory” to the functions of Xfunctions of X

• Spinal (from spinal cord)Spinal (from spinal cord)– Muscles that turn, tilt Muscles that turn, tilt

and thrust head and thrust head forwardforward

– Muscle that shrugs Muscle that shrugs shouldersshoulders

A more careful look at the muscles that A more careful look at the muscles that turn head and shrug shouldersturn head and shrug shoulders

• Sternocleidomastoid (#1 on left) Sternocleidomastoid (#1 on left)

• Trapezius (trapezoidal surface muscle in Trapezius (trapezoidal surface muscle in picture on right)picture on right)

Pathology (example of Pathology (example of damage to right cranial damage to right cranial nerve XI)nerve XI)• Difficulty turning head Difficulty turning head

away fromaway from the side of the side of the injured nerve (right the injured nerve (right sternocleidomastoid sternocleidomastoid turns head to the left)turns head to the left)

• Drooping shoulder on Drooping shoulder on side of injured nerveside of injured nerve

• Difficulty with arm Difficulty with arm movements above the movements above the shoulder on the affected shoulder on the affected sideside

Testing XITesting XI• Head turningHead turning

– Turn headTurn head– Turn head to resistanceTurn head to resistance

• Shoulder shruggingShoulder shrugging– Shrug shouldersShrug shoulders– Shrug shoulders to resistanceShrug shoulders to resistance

• Lift arm above shoulderLift arm above shoulder

MINI SELF-TESTMINI SELF-TESTWhich cranial nerves exit the cranium together, and thus Which cranial nerves exit the cranium together, and thus

“pattern” when damaged? What functions do these “pattern” when damaged? What functions do these cranial nerves fill, and thus, what functions may be cranial nerves fill, and thus, what functions may be

simultaneously affected?simultaneously affected?