CSD 4301 Intro to Audiology Study Guide

Pinna or auricle

Funnels sound through ear canal.

Ear canal

Cartilaginous portion is closest to the pinna.

Mastoid process

It is located above the ear.

Eustachian tube

It connects the middle ear to the back of the throat.

what are the two fluids in the inner ear?

The two fluids are perilymph and endolymph.

Tectorial membrane

It is a gelatinous mass that is shaped like a flap.

Outer hair cells

There are 3 rows of ______ hair cells.

Inner hair cells

There is 1 row of ________ hair cells.

What produces oxygen and nutrients for the cochlea?

stria vascularis

Tonotopic organization

The basal end of the cochlea is fine-tuned to high frequencies and the apical end is fine-tuned to low frequencies.

Auditory cortex

It is found in the temporal lobe of the brain.

Proprioceptive system

provides somatic sensory info on body part positioning.

Vestibular system

It provides input for angular acceleration through semicircular canals.

Otolith organs

They include utricle and saccule.

Semicircular canals (SCC)

Input for angular acceleration in vestibular system.

Utriculosaccular mechanism

Input for linear acceleration in vestibular system.

VOR (Vestibulo-Ocular Reflex)

Stabilizes vision during head movement.

Relay stations

Transmit auditory information to the brain.

Cochlear nucleus

First relay station for auditory information.

Superior Olivary Complex (SOC)

Processes sound from both ears.

Lateral Lemniscus

Pathway for auditory information to midbrain.

Inferior Colliculus

Integrates auditory information before thalamus.

Medial Geniculate Body

Thalamic relay for auditory signals.

dBHL

Decibel Hearing Loss, used in audiological testing.

dBSPL

Decibel Sound Pressure Level, measures sound intensity.

dBSL

Decibel Sensation Level, indicates hearing threshold.

Dynamic range

Difference between softest and loudest sounds heard.

Misophonia

Negative emotions triggered by specific sounds.

UCL (Uncomfortable Loudness Level)

Measured threshold of discomfort to sound.

MCL (Most Comfortable Level)

Level of sound perceived as comfortable.

Hyperacusis

Increased sensitivity to loud sounds.

Frequency range sensitivity

Ear most sensitive between 250-8000 Hz.

Audiogram

Graphical representation of hearing ability.

Speech banana

Area on audiogram showing audible speech sounds.

Air conduction pathway

Sound travels through outer, middle, inner ear.

Bone conduction pathway

Sound transmitted through bones of the skull.

Air-bone gap (ABG)

A greater than 10 dB difference between air conduction and bone conduction results.

Air Conduction Frequencies

Test frequencies: 1000, 2000, 4000, 8000.

Bone Conduction Frequencies

Test frequencies: 1000, 2000, 4000, 8000.

When ABG is greater than 10 dB we....

Go back and test at 750 and 1500 Hz

Conductive Hearing Loss

AC- loss, BC- normal, ABG- present.

Sensorineural Hearing Loss

AC- normal, BC- loss, ABG- absent.

Mixed Hearing Loss

AC- loss, BC- loss, ABG- present.

Normal Hearing Range

Normal hearing is 0 dBHL to 25 dBHL.

Minimal Loss Range

Minimal loss is 15 dBHL to 30 dBHL and is only used for children.

Mild Loss Range

Mild= 30 dBHL to 40 dBHL.

Moderate Loss Range

Moderate= 41 dBHL to 55 dBHL.

Moderate-Severe Loss Range

Mod/sev= 56 dBHL to 70 dBHL.

Severe Loss Range

Severe= 71 dBHL to 90 dBHL.

Profound Loss Range

Profound= 91 dBHL and above.

Corner Audiogram

A corner audiogram means that the patient has only low frequency hearing.

Pure Tone Average (PTA)

Calculate PTA by averaging thresholds at 500 Hz, 1000 Hz, and 2000 Hz.

Symmetrical vs Asymmetrical Hearing Loss

If there is a greater than 10 dB difference, the hearing loss is asymmetrical at that frequency.

SRT Stimuli

Stimuli used are spondee picture cards.

SRT Instructions

Repeat the two-syllable words exactly as you hear them.

Familiarization in SRT

Play the whole word list before dropping dB's.

WRA Stimuli

Stimuli used are monosyllabic phonetically balanced word lists.

WRA Carrier Phrase

Carrier phrase is 'say the word'.

WRA Testing Level for Normal Hearing

Normal hearing is tested at 30 dBSL above SRT.

WRA Testing Level for Hearing Loss

Hearing loss is tested at 40 dBSL above SRT.

why would masking be used during audiological testing?

Masking is used to prevent cross hearing.

Late Onset Hearing Loss

Hearing loss that develops after early childhood.

Behavioral Observation Audiometry (BOA)

Testing method using behavioral responses to sounds.

Limitations of BOA

Not reliable for consistent hearing assessment.

Visual Reinforcement Audiometry (VRA)

Uses visual rewards for sound detection in children.

Play Audiometry

Engages children through play for hearing tests.

Speech Awareness Threshold (SAT)

Lowest level at which speech is detected.

Stimuli for SAT

Typically includes simple sounds like 'hiiiiii'.

SRT vs. SAT

SRT measures speech recognition; SAT measures awareness.

Picture Spondee Cards

Used for testing with two-syllable words.

WIPI/NuCHIPs

Picture books for speech recognition testing.

One Syllable Words

Used for testing if pictures are unknown.

Tympanometry

Tests middle ear function using air pressure.

Type A tympanogram

Indicates normal middle ear function or sensorineural loss

Otoacoustic Emissions (OAE)

Tests cochlear function using sound emissions.

Automated Brain Response (ABR)

Measures brain response to auditory stimuli.

Click Stimuli

Used in ABR testing for auditory response.

ASSR

Auditory steady-state response testing method.

Non-Organic Hearing Loss

Hearing loss without a biological cause.

Red Flags for Non-Organic Loss

Inconsistent SRT with pure tone audiometry.

Universal Newborn Hearing Screening

Mandated since 1999 for early detection.

1-3-6 Rule

Diagnose by 1 month, intervention by 6 months.

Otomycosis

Fungal infection in the ear canal.

Microtia

Congenital deformity of the outer ear.

Anotia

Absence of the external ear (pinna).

Stenosis

Extreme narrowing of the ear canal.

what are examples of foreign bodies

Objects like rocks or beads in the ear.

Atresia

Absence of the ear canal.

Glue Ear

Thick mucus buildup in the middle ear.

Middle Ear Infection

Infection of the middle ear lining.

Cholesteatoma

Pseudotumor formed by skin in the middle ear.

Mastoiditis

Infection of the mastoid bone.

Eustachian Tube Dysfunction

Blocked Eustachian tube causing middle ear pressure.

Otosclerosis

Spongy bone growth over stapes footplate.

TM Perforation

Hole in the tympanic membrane.

Tympanosclerosis

Calcium plaque buildup on the tympanic membrane.

Toxoplasmosis

Toxins in the bloodstream affecting hearing.

Zika

Virus transmitted by bugs causing hearing loss.

CMV

Viral disease leading to bilateral sensorineural loss.

Genetic Autosomal Recessive

Recessive gene causing hearing loss in offspring.