Audiology

Basic Audiological Evaluation

HHI

Hearing Handicap Inventory

25 Item questionnaire completed by adult patients to assess the patient's perception of communication difficulties related to hearing

includes emotional and social situations

Audiology

Basic Audiological Evaluation

Hearing Threshold

lowest level at which the listener can detect a sound

- measured in dB HL

- behavioral response required

Audiology

Basic Audiological Evaluation

Humans are most sensitive to sound frequencies...

...between 1000 & 4000 Hz

Audiology

Basic Audiological Evaluation

ANT

Average Normal Threshold

set to 0 dB HL

reference point for normal hearing

Audiology

Basic Audiological Evaluation

Air Conduction Measurement

different pure-tone stimuli are transmitted through earphones, one ear at a time

- reflect the integrity of the total peripheral auditory mechanism

Audiology

Basic Audiological Evaluation

Sound Field Testing

Audiology

Basic Audiological Evaluation

Pure Tone Sequence

According to ASHA: 1000Hz, 2000Hz, 3000Hz, 4000Hz, 6000Hz, 8000Hz, retest 1000Hz (first ear only), 500Hz, 250Hz

test interoctaves such as 750Hz and 1500Hz only if there is a 20 dB or greater difference between thresholds at adjacent octave intervals

Audiology

Basic Audiological Evaluation

Bone Conduction Thresholds

- pure tones are transmitted via bone vibrator place on the mastoid process or forehead

- represent the sensitivity of the sensorineural system

- not ear specific unless masking is used 

Audiology

Basic Audiological Evaluation

Air Conduction Testing Vs. Bone Conduction

Bone Conduction only tests: 1000, 2000, 4000, 500, 250 Hz

Maximum intensity limit is lower

BC not usually done if AC thresholds are normal

Audiology

Basic Audiological Evaluation

Factors that Influence Threshold

proper maintenance and calibration of audiometer

- biological calibration done daily (audiologists screen themselves)

- electronic calibration done at least once yearly

earphone placement

- too loose: increase in low frequence thresholds

- standing waves: increase high frequency thresholds

Audiology

Basic Audiological Evaluation

Hearing Loss is Described in Terms of:

Degree

Type (conductive, sensorineural, mixed)

Configuration

Audiology

Basic Audiological Evaluation

Categories of Hearing Loss

-10 to 15 dB HL - normal

16 to 25 dB HL - slight hearing loss (WNL for adults)

26 to 40 dB HL - mild hearing loss

41 to 55 dB HL - moderate hearing loss

56 to 70 dB HL - moderately-severe hearing loss

71 to 90 dB HL - severe hearing loss

>91 dB HL - profound hearing loss

Audiology

Basic Audiological Evaluation

Degree of Hearing and Speech

Normal Limits - no significant difficulty with faint speech

Mild - difficulty only with faint speech

Moderate - frequent difficulties with normal speech

Moderately Severe - frequent difficulty with loud speech

Severe - can only understand shouted or amplified speech

Profound - usually cannot understand even amplified speech

Audiology

Basic Audiological Evaluation

Pure Tone Average

Audiology

Basic Audiological Evaluation

Type of Loss and Site of Dysfunction

Conductive Loss

Audiology

Basic Audiological Evaluation

Type of Loss and Site of Dysfunction

Sensorineural Loss

Audiology

Basic Audiological Evaluation

 Type of Loss and Site of Dysfunction

Mixed Loss

Audiology

Basic Audiological Evaluation

Air-Bone Gap

One or more bone conduction thresholds better than the air conduction threshold by more than 10 dB 

- means there is a conductive component present

- may require a medical referral

Audiology

Basic Audiological Evaluation

Hearing Loss Configurations

flat 

sloping - high frequencies worse

rising - low frequencies worse

notched - specific frequency range worse

cookie bite - mid frequencies are worse

symmetrical/asymmetrical - between the two ears

bilateral/unilateral - both ears, or just one ear

Audiology
Inner Ear Anatomy

Cochlear Portion 

- end organ of hearing

- converts mechanical energy to hydraulic energy to neuroelectric energy

- essentially a transducer that changes energy from one type to another

Audiology 

Inner Ear Anatomy

Helicotrema

Audiology 

Inner Ear Anatomy

Scala Vestibuli

- separated from scala media by Reissner's Membrane

- receives stapes vibrations via the vestibule

- oval window separates it from the middle ear

- contains perilymph

Audiology 

Inner Ear Anatomy

Scala Tympani

Separated from scala media by Basilar Membrane

separated from the middle ear space by the round window

contains perilymph

Audiology 

Inner Ear Anatomy

Scala Media

aka cochlear duct

membranous labyrinth in the cochlea

filled with endolymph

separates perlymphatic space into scala vestibuli and scala tympani

continuous from base to apex

Audiology 

Inner Ear Anatomy

Modiolus

bone core and central pillar of the cochlea

cavities present throughout that contain the cell bodies of auditory nerve fibers

-collectively known as spiral ganglion

Audiology 

Inner Ear Anatomy

Basilar Membrane

- separates scala tympani from scala media

- supports organ of corti

- narrower and tenser at base, wider and looser at apex

Audiology 

Inner Ear Anatomy

Spiral Modiolar Artery

single source of blood supply to cochlea

if damaged, result is sudden hearing loss

Audiology 

Inner Ear Anatomy

Organ of Corti (spiral organ)

sensory end organ of hearing

on basilar membrane

contains sensory cells (inner and outer hair cells) and supporting cells

Audiology 

Inner Ear Anatomy

Inner Hair Cells

3000 to 3500 total

shallow, u-shaped stereocillia - allows more sensory nerve fibers to attach directly to the base

most afferent

fewer in number than outer hair cells, but more important for receiving and sending info to the brain

Audiology 

Inner Ear Anatomy

Outer Hair Cells

12,000 to 13,500

w or v-shaped stereocilia that make contact with tectorial membrane

more efference synapses

Audiology

Innter Ear Function

Transduction Process

stapes pushes in and out against perilymph

vibrations converted to hydraulic energy

traveling wave motion from base of cochlea to apex

vertical displacement at peak of traveling wave

shearing motion between tectorial and basilar membranes

bending of sterocilia on top of hair cells

release of neurotransmitter at base of hair cells

firing of auditory nerve fibers synapsing with hair cells

Audiology

Inner Ear Function

Place Theory

- best explains good high-frequency discrimination

- tonotopic organization - mapping of frequency of the sound wave to place of maximum activity within anatomic structure

- characteristics of basilar membrane determine where maximum amplitude for a particular frequency will occur

- high frequencies at base

- low frequencies at apex

Audiology

Inner Ear Function

Phase Locking

- best explains good low-frequency discrimination

- auditory nerve fibers fire in synchrony with each cycle of vibration

- nerve fibers limited to how fast they can fire (about 1000/second) so phase-locking mechanism works for low frequencies

Audiology

Middle Ear Anatomy

Laters of the Tympanic Membrane

Lateral Layer

epithelial

continuous with skin of external auditory canal

Audiology

Middle Ear Anatomy

Laters of the Tympanic Membrane

Medial Layer

mucous membrane

continous with mucosal lining of the middle ear space

Audiology

Middle Ear Anatomy

Laters of the Tympanic Membrane

Core or Middle Layer

sandwiched between other layers

not present through entire TM, but present through about 85% (Pars Tensa is area where Core is present, Pars Flaccida is area where it's not)

Audiology

Middle Ear Anatomy

Eustachian Tube

- connects middle ear to nasopharyngeal cavity

- osseous portion (in middle ear cavity) is always open

- cartilaginous portion (towards nasopharynx) normally closed

- opens during yawning, swallowing, chewing

- opened by the tensor veli palatini

Audiology

Middle Ear Anatomy

Eustachian Tube Function

equalization of air pressure

ventilation of the middle ear space

drainage of middle ear scretions

Audiology

Anatomy of the Hearing Mechanism

Peripheral Section and Central Section

peripheral: includes structures from the outer ear through the auditory nerve

central: begins at the cochlear nucleus and ends at the auditory centers of the cortex

"ear" refers to the entire peripheral auditory mechanism

Audiology

Anatomy of the Hearing Mechanism

Outer Ear Function

- funnels sound into the auditory system

- assists with front-back localization of sound

- provides enahancement of mid to high frequencies (2500-5500 Hz)

- protects middle ear against for objects, temperature changes, etc

Screening and Threshold

Joint Committee on Infant Hearing

EHDI

Early Hearing Detection and Intervention

- infants' hearing screen before discharge from the hospital, or prior to one month of age

- hearing impairment diagnosed by three months of age

- child is in an intervention program by six months of age

Screening and Threshold

Screening Infants

ABR

Auditory Brainstem Response

- assesses function of auditory system up to level of auditory brainstem

Screening and Threshold

Screening Infants

OAE

Otoacoustic Emissions

assesses outer hair cell function

typically absent with sensorineural loss of 30-40 dB HL and higher

can also be affected by middle ear dysfunction

Screening and Threshold

School Age Children

What grade levels are screened?

first and third

sometimes fifth, seventh and ninth

Screening and Threshold

Screening School Age Children

Screening Protocol

screening level: 20 dB HL

frequencies: 1000, 2000, 4000 Hz

referral: if any one frequency is missed in either ear

- screening at 500 was discontinued because highly succeptible to background noise

Disorders

Classification of Disorders

Classified by:

etiology

onset

site of lesion

Disorders

Disorders of the Outer Ear

Anotia

Disorders

Disorders of the Outer Ear

Microtia

deformity of the pinna - abnormally small, absence of landmarks

congenital

Disorders

Disorders of the Outer Ear

Cauliflower Ear

acquired

partially deformed pinna due to repeated injury

Disorders

External Auditory Canal Disorders

Atresia

congenital

complete or parital absence or closure of the external auditory canal

Disorders

Ear Canal Disorders

Impacted Cerumen

acquired

occurs when cerumen completely blocks the ear canal

risk factors: consistent use of ear plugs, hearing aids, q-tips; presence of congenital stenosis or foreign object

best treated by prevention

Disorders

Ear Canal Disorders

External Otitis - Acute

acquired

aka "swimmer's ear"

inflammation of the skin of the external auditory canal

often bacterial infection related to excessive water exposure

symptoms: itching, swelling, discharge, pain

Disorders

Ear Canal Disorders

External Otitis

Chronic

acquired

can result from bacterial or fungal infection, skin condition, allergy, chronic drainage from middle ear infection

treated weith aeration of ear canal, antibiotic ear drops, debris clearance

Disorders

Middle Ear Disorders

Tympanic Membrane Perforation

trauma or disease process

likely to cause hearing loss

most recover spontaneously

surgical repair (myringoplasty) sometimes necessary

Disorders

Middle Ear Disorders

Tympanosclerosis

calcium deposits formed on TM (aka scarring of the TM)

typically associated with chronic otitis media or trauma to TM

Disorders

Middle Ear Disorders

Otitis Media

infection of the middle ear space

acute (sudden, lasts 0-3 weeks, occurs with fever, nasal congestion, inability to sleep, pain) or chronic (longer than three months)

Disorders

Middle Ear Disorders

Otitis Media

Serous

Disorders

Middle Ear Disorders

Otitis Media

Suppurative, purulent

Disorders

Middle Ear Disorders

Otitis Media

Mucoid

Disorders

Middle Ear Disorders

Otitis Media High-risk Factors

- very young children

- day care or multiple children living at home

- hispanic or native american

- cleft palate

- down syndrome

-suppressed immune system

- second-hand smoke

Disorders

Middle Ear Disorders

Otitis Media Treatment

- resolves naturally, treat symptoms

antibiotics

pressure equalization (venilation tubes)

Disorders

Middle Ear Disorders

Otitis Media

Potential Medical Complications

erosion of ossicles

erosion into labyrinth (fistula)

erosion and exposure of facial nerve

mastoiditis

cholesteatoma

meningitis, encephalitis

Disorders

Middle Ear Disorders

Cholesteatoma

"pseudo tumor" arising from skin cells trapped in the middle ear behind the tympanic membrane

primarily acquired, but can be congenital

symptoms: drainage, ear aches, feeling of pressure, hearing loss - occasionally dizziness or facial muscle weakness

intervention: controlling otitis media, surgery for removal, middle ear reconstruction

Disorders

Middle Ear Disorders

Otosclerosis

abnormal spongy bone deposits in middle ear

prevalence: most common cause of serious hearing loss in young adulthood

1 in 5-10 Anglo women

hereditary 

onset in 20s to early 40s

progressive, often bilateral

treatment: surgical (stapedectomy) or hearing aids

Disorders

Middle Ear Disorders

Ossicular Disarticulation

typically acquired

separation of ossicular chain due to trauma or disease

can be partial or complete

80% have erosion of incudo-stapedial joint, which is weakest part of ossicular chain

Syndromes

Treacher Collins Syndrome

-very small jaw; cleft palate common

- eyes slant downwards, away from nose

- coloboma (notch or cleft) on lower lid

- abnormal or almost completely missing pinnas

-atresia or stenosis of external auditory canal

malformed or missing ossicles

- underdeveloped cheek bones

-large mouth, often with dental abnormalities

Syndromes

Treacher Collins Syndrome

Continued

- autosomal dominant inheritance

(more than 1/2 of cases are fresh mutations)

- typically conductive hearing loss with mild to moderately severe degree, and a rising or flat configuration

- inner ear structures typically normal, but in rare cases, sensorineural component present

Disorders

Sensorineural Disorders

Genetic Hearing Loss 

Types of Inheritance

autosomal dominant inheritance - 20% of genetic hearing loss incidences

autosomal recessive inheritance - majority (80%) of all genetic hearing loss incidences

x-linked inheritance - passed from mother to son - rare, only 2-3% of genetic hearing loss incidences

Disorders

Sensorineural Disorders

Autosomal Dominant Inheritance

- gene for HL exists on one of the non-sex-determining chromosome pairs

- if HL gene inherited from either parent, hearing loss is demonstrated. 

- 50% chance of child inheriting hearing loss

Syndromes

Waardenburg's Syndrome

- may have absence of Organ of Corti and atrophy of spiral ganglion

- white forelock

-iris bicolor (heterochromia)

- facial abnormalities

- Autosomal Dominant Syndrome

Disorders

Sensorineural Disorders

Autosomal Recessive Inheritance

- gene must be present in both parents to cause hearing impariment

- 25% chance of any child inheriting hearing loss

- 50% chance child will carry HL gene

Syndromes

Usher's Syndrome

congenital deafness

progressive loss of vision (retinitis pigmentosa) that leads to eventual blindness

Syndromes

Pendred's Syndrome

goiter - hyper active thyroid

profound deafness

often has enlarge vestibular aqueduct syndrome

Syndromes

Enlarged Vestibular Aqueduct Syndrome

- most commonly identified inner ear bony malformation in children with sensorineural hearing loss of unknown origin

- more often bilateral

- associated with other inner ear abnormalities

- sensorineural hearing loss at birth or onset in childhood

- often progressive, sometimes suddenly, and reported after minor head injuries

recessive genetic disorder

children with EVAS sometimes become CI candidates

Disorders

Congenital Infections

TORCHeS

Toxoplasmosis: caused by parasite transmitted to child via placenta

Rubella - maternal contracted; earlier infection increases risk of HL; possibly accompanied by heart/kidney defects; bilateral, severe to profound hearing loss

Cytomegalovirus - most common viral disease known to cause hearing loss; over 50% of symptomatic children will have HL

Herpes Simplex Virus - sexually transmitted, passed to fetus in utero, most infected infants have complications

Syphilis - transmitted in utero, may manifest up to 60 years later, if it activates before 10 years of age, HL often profound and bilateral with sudden onset

Disorders

Sensorineural Disorders

Early Risk Factors

hyperbilirubinemia

trauma at birth

medication taken or drug abuse during pregnancy

low birth weight

Disoders

Sensorineural Disorders

Postnatal Infections

Bacterial Meningitis

leading cause of acquired childhood severe sensorineural hearing loss

can affect cochlea, auditory nerve, CANS

up to 30% of cases have hearing loss

Disoders

Sensorineural Disorders

Postnatal Infections

Mumps and Measels

Disorders

Sensorineural Disorders

Ototoxic Medications

Disorders

Sensorineural Disorders

Meniere's Disease

excess fluid in inner ear

progressive or fluctuating, low frequency hearing loss

episodic vertigo

tinnitus, feeling of fullness in ear

bilateral or unilateral (more often unilateral)

treated with low sodium diets, diuretics, sedatives, vestibular suppressants, endolymphatic shunt surgery, destruction of the labyrinth/cutting of auditory nerve

Disorders

Sensorineural Disorders

Noise Induced Hearing Loss

Almost always bilateral, but can be asymmetrical

affects frequencies between 3000 and 6000 Hz first

hair cells and other cochlear structures damaged or destroyed

dependent on intensity, spectrum of noise, duration of exposure, and individual resistance

Disorders

Sensorineural Disorders

Presbycusis

age-related hearing loss (50 years and older)

affects cochlea, but can also affect auditory nerve and CANS, eventually

high frequencies affected first

bilateral, symmetrical, typically mild to moderate hearing loss

Disorders

Retrocochlear Disorders

Acoustic Neuroma

poor word recognition

most commonly a tumor of the temporal bone

almost always unilateral

tinnitus and dizziness are common symptoms

affects high frequencies first

benign, slow-growing tumor compressing the nerve

Speech Audiometry

Speech Detection Threshold (SDT)

aka Speech Awareness Threshold

minimum hearing level at which an individual can just detect the presence of speech material

- should be consistent with the best pure tone threshold between 250 and 4000 (+ or - 5 dB)

Speech Audiometry

Speech Recognition Threshold

minimum hearing level for speech at which an individual can identify simple speech materials 50% of the time

should correspond to pure tone average with 10 dB

used as reference point to determine optimal presentation level for suprathreshold (+40 dB HL to SRT)

Speech Audiometry

Spondaic Words

two-syllable words with equal emphasis on each syllable

used in SRT

Speech Audiometry

Suprathreshold Performance

individual's ability to identify speech materials at intensity above threshold level

- at least 40 db SL above PTA or SRT

- present at high intensity to screen for retrocochlear pathology

Speech Audiometry

Rollover

abnormal performance intensity - performance decreases with increasing intensity of speech

- consistent with retrocochlear pathology

Auditory Nerve (8th Cranial Nerve)

Hair Cell Innervation

90-95% of afferent auditory nerve fibers synapse with inner hair cells

only 5% of afferent fibers synapse with outer hair cells

Auditory Nerve (8th Cranial Nerve)

Parts

Auditory Nerve (8th Cranial Nerve)

Connection to the Brainstem

enters at the cerebellopontine angle

ends at the cochlear nucleus

Auditory Central Nervous System

Major Nuclei

cochlear nucleus: beginning of auditory CNS; receives ipsilateral information only

superior olivary complex: in pons, medial and deep to cochlear nucleus. first level of CANS that receives info from both ears simultaneously. important in binaural processing; regulates stapedial muscle reflex

Inferior Colliculus: midbrain; important in binaurl processessing

Medial Geniculate Bodies: thalamus; last subcortical way station - all ascending fibers terminate in one of the medial geniculate bodies before information ascends to the cortex

Primary Auditory Cortex: cerebrum; final destination for ascending auditory nerve fibers; connects to Wernicke's

Aural Rehabilitation

Hearing Loss Effect on Speech Features

250-500 Hz

suprasegmental elements

consonant voicing

nasality

first formant information of high vowels

Aural Rehabilitation

Hearing Loss Effects on Speech

1000 Hz

all things lost affected at 250-500Hz, plus

manner of articulation cues

vowel formant information

some stop bursts

Aural Rehabilitation

Hearing Loss Effect on Speech

2000-4000 Hz

non-resonant consonants (fricatives, affricates, plosives)

differentiation of liquids (l,r)

second formants of front vowels

Aural Rehabilitation

Assistive Listening Devices

Hard Wired Systems

-less expensive

-good sound quality

-may have limited mobility

-external microphones coupled to hearing aid with direct audio input (DAI)

-"pocket talker"

Aural Rehabilitation

Assistive Listening Devices

Wireless Systems

-more expensive

-good sound quality

-better mobility

-possibility of interference

-sound picked up by external mic, electrical signal passed to transmitter, then to receiver

Aural Rehabilitation

Assisted Listening Devices

Types of Wireless Systems

- Inductive Loop System (relative low cost; requires functioning aid with strong telecoil; lack of portability)

- Infrared System (concerts, personal TV devices; not coupled with personal hearing aid, must face emitter; interference from natural light possible)

- FM System (frequency modulated; helps overcome effects of background noise, competing conversations, distant speakers, improve listening in rooms with poor acoustics, reduces listening effort)

- Personal FM System (receiver plugs directly into sound processor and/or hearing aid; provides 15-20 dB SNR advantage; travels; small size)

Aural Rehabilitation

Cochlear Implants

CI Components

External

-microphone

-speech processor

-transmitter (coil)

Aural Rehabilitation

Cochlear Implants 

Cochlear Components 

Internal Components (implanted)

internal receiver - sends signal to electrodes

electrode array

Aural Rehabilitation

Cochlear Implant

Acitvation and Mapping

T-Levels

Aural Rehabilitation

Cochlear Implants

Activation and Mapping

C-Levels

Aural Rehabilitation

Cochlear Implants

Number of Channels

4 channels: optimal speech recognition in quiet

5 channels: more difficult sentences

12 channels: monosyllabic words in noise

16 channels: recognition of music

- Most patients get up to 8 channels due to frequency mismatch or missing neurons in cochlea

Aural Rehabilitation

Cochlear Implants

Candidacy

Adults

profound bilateral hearing loss

deafened after five years old

little to no benefit from hearing aids (<50% word recognition)

psychologically and motivationally suitable

Aural Rehabilitation

Cochlear Implants

Candidacy

Pediatric

- 12 months or older with profound hearing loss bilaterally

- 18 months or older with severe to profound bilateral hearing loss

- little/no benefit from hearing aids (requires 3-6 month trial with hearing aids)

- lack of progress in auditory skills

- medically cleared for surgery

- high motivation and appropriate expectations of family

- placement in education setting able and willing to provide concentrated auditory skill development program

Aural Rehabilitation

Cochlear Implants

Borderline Candidates

Additional Considerations

- child's spoken language

- progress in treatment

- social functioning

- academic functioning

- classroom comprehension

Aural Rehabilitation

Cochlear Implants

Auditory Function of Adult CI Users

- improved detection/awareness of sound

- improved recognition of environmental sounds

- enhanced speech reading abilities

- open-set speech recognition possible, particularly with visual cues

- average word in sentence recognition for postlingually deafened adults with new CIs after six months is 90%

Aural Rehabilitation

Cochlear Implants

Factors Affecting Performance

Adults

- duration of deafness (<10 years best, <15-20 is okay)

- cochlear anatomy

- prior hearing aid use

- spoken language

- family and friend support

- functioning auditory nerve

Aural Rehabilitation

Cochlear Implants

Pediatric Outcome Factors

- age of onset

- age at identification

- age of intervention (type and quality)

- age at implantation **

- motivation of family and child

- presence of additional disorders

children implanted <18mos with appropriate habilitation, family support, and school placement have best prognosis

Aural Rehabilitation

Cochlear Implants

Trends

- younger age/better outcomes

- more children with multiple disabilities being implanted

- numbers/proportion of children rising

- auditory approaches on the rise

- broader interest/acceptance

- trend toward implantation of children with better hearing

- surgical advances - ossified and malformed cochleas not always a contraindication for implantation

- binaural implantation (sequential or simultaneous)

Aural Rehabilitation

Functional Assessments

ELF: Early Listening Function (preschool)

LIFE: Listening Inventory for Education (school-age)

HHI: Hearing Handicap Inventory (adults)

Motor Speech Disorders

The Processing Model of Speech

ideation -> linguistic planning (word retrieval, phonological mapping, syntactic/grammatical ordering) -> motor planning/programming -> performance/execution -> feedback -> ideation

-loop that repeats itself

Motor Speech Disorders

Apraxia

Motor Speech Disorders

Dysarthria

Motor Speech Disorders

Motor Speech Disorders

Motor Speech Disorders

Neurologic and Etiologic Variables

age at onset

course (congenital, chronic, progressive, degenerative)

site of lesion

neurologic diagnosis

pathophysiology (weakness, spasticity, etc)

corical or peripheral

Motor Speech Disorders

Cranial Nerves Innervate All Speech Muscles Except...

Motor Speech Disorders

oligodendroglia

Motor Speech Disorders

schwann cells

Motor Speech Disoders

Localization

Focal

Motor Speech Disoders

Localization

Multifocal

Motor Speech Disorders

Localization

Diffuse

Motor Speech Disorders

Etiologic Categories

degenerative: gradual decline in neuronal function; chronic or progressive

inflammatory: reach peak; trademark is white blood cell output

toxic-metabolic: reaction to not processing something correctly; drugs, toxins, etc

neoplastic: neoplasms, tumors; invasion of spontaneous growth of tissue

traumatic disease: usually has an identifiable precipitating event; excluding subdural hematoma

Motor Speech Disorders

Final Common Pathway

1.peripheral mechanism that mediates all motor activity

2.last link in chain of events leading to movement

3.extrafusal fibers under direct control from LMNs

4.axon leaves brainstem or spinal cord in a nerve and travels to specific muscle 

5.axon may innervate several muscles, and each muscle fiber receives input from several alpha motor neurons

6. gamma motor neurons innervate intrafusal fibers crucial to maintaining muscle tone

7. GMNs strongly influenced by cerebellum, basal ganglia, indirect pathways to CNS

8. ALL tracts feed to final common pathway

Motor Speech Disorders

Final Common Pathway for Speech

Motor Speech Disorders

Nerves

Cranial Nerve #5 

Trigeminal

sensory: pain, thermal, and tactile sensation from face and forehead, mucous membranes of nose, mouth, teeth, gums, hard palate

motor: muscles of mastication, tensor tympani, tensor veli palatini

Motor Speech Disorders

Cranial Nerves

Cranial Nerve #7

Facial

motor: stapedius muscles, muscles of facial expression

sensory: submandibular and lacrimal glands; taste (anterior 2/3 of tongue)

Motor Speech Disorders

Cranial Nerves

Cranial Nerve #9

Glossopharyngeal

motor: stylopharyngeus muscle of pharynx

sensory: pharynx, tongue, eustachian tube

Motor Speech Disorders

Cranial Nerves

Cranial Nerve #10

Vagus

motor: soft palate, pharynx, larynx

sensory: same structures

superior and recurrent laryngeal nerves are responsible for ALL laryngeal motor activities

Motor Speech Disorders

Cranial Nerves

Cranial Nerve #10

Vagus Nerve Lesions

unilateral LMN damage of Vagus affects: resonance, voice quality, swallowing

bilateral LMN damage of Vagus affects: resonance, phonation, prosody, articulation, swallowing

Motor Speech Disorders

Cranial Nerves

Cranial Nerve #11

Spinal Accessory

Motor Speech Disorders

Cranial Nerves

Cranial Nerve #12

Hypoglossal

motor: all intrinsic and all but one extrinsic muscle of the tongue

sensory: taste and tactile information from the nucleus of the tractus solitarius and sensory trigeminal nucleus. important for: speech, chewing, sucking, swallowing

Motor Speech Disorders

Dysarthrias

Flaccid Dysarthria

Locus

Lower motor neurons

unilateral or bilateral

spinal or cranial nerves

Motor Speech Disorders

Dysarthrias

Flaccid Dysarthria

Primary Unique Deficit

Motor Speech Disorders

Dysarthrias

Flaccid Dysarthria

Distinguishing Speech Characteristics

Motor Speech Disorders

Dysarthrias

Flaccid Dysarthria

Confirmatory Signs

Motor Speech Disorders

Dysarthrias

Flaccid Dysarthria

Etiologies

Motor Speech Disorders

Dysarthrias

Flaccid Dysarthria

Symptom Clusters

phonatory: breathiness, short phrases, audible inspiration

resonatory: hypernasality, nasal emissions, imprecise consonants, short phrases

phonatory-prosodic insufficiency: harshness, monopitch, monoloudness

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Locus

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Primary Unique Deficit

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Distinguishing Speech Characteristics

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Confirmatory Signs

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Etiologies

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Symptom Clusters

Prosodic Excess: excess and equal stress, slow rate

Phonatory Insufficiency: reduced variability and ROM, short phrases, monopitch, monoloudness, reduced stress

Prosodic Insufficiency: harshness, strained stranged voice, short phrases, low pitch, pitch breaks, slow rate

Articulatory-Resonatory Incompetence: imprecise consonants, hypernasality, distorted vowels

Motor Speech Disorders

Dysarthrias

Ataxic Dysarthria

Locus

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Primary Unique Deficit

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Distinguishing Speech Characteristics

irregular and transient articulatory breakdowns

irregular AMRs, excess and equal stress, excess and equal loudness, dysprosody, vowel distortions

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Confirmatory Signs

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Etiologies

anything that can damage the cerebellum

degenerateive disease, toxic metabolic disorders, neoplasms, vascular disease, trauma

Motor Speech Disorders

Dysarthrias

Spastic Dysarthria

Symptom Clusters

Articulatory: irregular breakdowns, imprecise consonants, vowel distortions

Prosody: excess/equal stress, prolonged phonemes and intervals, slow rate

Phonatory-Prosodic Insufficiency: harshness, monopitch, monoloudness, variable, sudden loudness

Motor Speech Disorders

Dysarthrias

Hypokinetic Dysarthria

Locus

Motor Speech Disorders

Dysarthrias

Hypokinetic Dysarthria

Primary Unique Deficit

Motor Speech Disorders

Dysarthrias

Hypokinetic Dysarthria

Distinguishing Speech Characteristics

Motor Speech Disorders

Dysarthrias

Hypokinetic Dysarthria

Etiologies

Motor Speech Disorders

Dysarthrias

Hypokinetic Dysarthria

Symtom Clusters

Motor Speech Disorders

Dysarthrias

Unilateral Upper Motor Neuron Disease

Locus

Motor Speech Disorders

Dysarthrias

Unilateral Upper Motor Neuron Disease

Primary Unique Deficit

Motor Speech Disorders

Dysarthrias

Unilateral Upper Motor Neuron Disease

Distinguishing Speech Characteristics

Motor Speech Disorders

Dysarthrias

Unilateral Upper Motor Neuron Disease

Confirmatory Signs

Motor Speech Disorders

Dysarthrias

Unilateral Upper Motor Neuron Disease

Etiologies

Motor Speech Disorders

Dysarthrias

Differential Diagnosis (Speech Characteristics)

flaccid: phonatory and resonatory abnormalities

spastic: slow rate, slow and regular AMRs, strained-strangled voice

ataxic: irregular articulatory breakdowns, irregular speech AMRs, dysprosody

Hypokinetic: monopitch/loudness, reduced stress and loudness, rapid rate, rapid and blurred AMRs

UUMN: mildness and nebulous speech characteristics

Motor Speech Disorders

Management

Key Words

Motor Speech Disorders

Management

Disability

Motor Speech Disorders

Management

Handicap

Motor Speech Disorder

Management

Five Areas of Management

Medical

Prosthetic

Behavioral

Augmentative

Counseling and Support

Motor Speech Disorders

Management

Motor Learning Principles

1. patient's understanding of management is crucial

2. improving speech requires speaking

3. motor learning includes: cognitive, associative, and autonomous stages

4. drill is essential

5. instruction improves performance

6. self-learning is valuable

7. feedback is essential to motor learning

8. specificity of training

9. consistent practice and variable practice have value

10. speed and accuracy are a trade off

Motor Speech Disorders

Managment

Speaker Oriented Treatments

Flaccid Dysarthria

treatments designed to improve strength or compensate for weakness

aimed at respiratory, laryngeal, resonatory and articulatory components of speech

Motor Speech Disorders

Managment

Speaker Oriented Treatments

Spastic Dysarthria

hyperadduction a problem, so relaxation techniques may be more appropriate here

management of pseudobulbar affect more common in spastic

Motor Speech Disorders

Managment

Speaker Oriented Treatments

Hypokinetic

similar to flaccid

surgical interventions to remove effects of movement disorders

some medications helpful to varying extents, and usually more effective on non-speech functions

LSVT (particularly for Parkinson's)

Motor Speech Disorders

Managment

Speaker Oriented Treatments

Ataxic Dysarthria

focus is behavior

activities centered on improving or compensating for motor control and coordination

modifying rate and prosody

modifying stress and loudness

Motor Speech Disorders

Managment

Speaker Oriented Treatments

Hyperkinetic