Audiology and Hearing Science Vocabulary

Flashcards testing terminology, anatomical structures, diagnostic tests, and acoustic concepts from the audiology lecture notes.

Audiology

The study of hearing.

Coined by Dr. Carhart and Dr. Canfield

What’s the profession of audiology?

Administer and conduct hearing screening programs

• Evaluate and treat hearing loss, tinnitus (sounds, specifically of a buzzing nature, perceived in the ear in the absence of an external

ringing or

stimulus)balance and related disorders

• Recommend and provide appropriate technology

• Provides audiological rehabilitation

Various roles of audiologist

Diagnostic evaluations (pedsgeriatric)

• Hearing aids

• Intraoperative monitoring

• Otoxicity (certain drugs that affect hearing loss)

• Hearing conservation

• Cochlear implants

• Auditory processing evaluations

• Telepractice/remote audiology

• Research

• Auditory training

• Deaf education

• Vestibular rehabilitation• Tinnitus rehabilitation

What’s the scope of practice in audiology?

Works primarily focuses on hearing, balance and tinnitus

Why does one become a audiologist?

Hearing care professionals are secured top spots in U.S. News and World Report

100 Best Jobs for 2025 recognized for their strong job prospects, wage potential and work life balance

• Job growth for audiology is expected to grow by 13% from 2019 to 2029 (much faster than the average for other occupations)

About 800 openings for audiologists are projected each year on average over the decade

Tinnitus

Sounds, specifically of a ringing or buzzing nature, perceived in the ear in the absence of an external stimulus.

Au.D.

Doctor of Audiology; the professional doctoral degree required for practicing audiologists in the U.S., consisting of a 4-year program with 2000 clinical hours/externship.

Ph.D. in Audiology

Doctor of Philosophy degree in audiology, which is generally research-focused.

Criteria in Audiology

1. Baccalaureate degree

2. Admission to a Au.D program (4 year program after earning bachelor

degree)

3. 4 year program with 2000 clinical hours/externship

4. Certification (CFY)

5. State Licensure

6. Continue education units (CEU’s)

____ of American Adults (37.5 million ages 18 and over) report some degree of hearing loss and trouble hearing

15%

The prevalence of hearing loss is _____

twice as common as diabetes or cancer

_____ is the strongest predictor of hearing loss among increasing once they reach _____

Age, 60

____ are almost twice likely as women to have hearing loss among 20-29

Men

Hearing loss in children

Ability to develop speech, language and social skills

• Earlier stages of hearing loss start getting services (the more likely they will

reach their full potential)

• They will get a hearing screening

Hearing loss in adults

Vocational issues

• Social and psychological influences

• All ages are affected like 60• Noise expourse, ototoxicity (certain drugs) genetics, pathologies, aging• Link to dementIs

Conductive Hearing Loss

caused by a pathology in the outer or middle ear that obstructs the physical transmission of sound to the cochlea.

• Sound has trouble conducting through the outer/middle ear

Example- earwax blockage, fluid in the middle, ear infection, problems with the ossicles and perforated eardrum

Sensorineural Hearing Loss

caused by damage to the inner ear/cochlea or auditory nerve pathways to the brain.

Examples-

• gaining

• Damage to the cochlear’s hair cells

• Noise expourse

Diseases

Sensory structures + neural pathway

Mixed Hearing Loss

caused by a combination of both conductive and sensorineural components. Both the outer/middle ear AND inner ear/auditory nerve

Outer ear

Pinna (helix and lobule)- The visible part of the ear that collects sound and directs it into the ear canal.

External Auditory meatus/canal (ear canal)- carries sound towards the eardrum

Tympanic membrane (eardrum)- vibrates when sound waves hit it

Middle Ear

Auditory ossicles- Three tiny bones in the middle ear—malleus, incus, and stapes transfer/amplify vibrations from the eardrum toward the inner ear.

Eustachian Tube- helps equalize pressure and drain fluid from the middle ear (example- when you’re on a airplane and your ears “pop” the tub is involved and problems cause conductive hearing loss)

Inner Ear

the important structure of hearing

Cochlea- the cochlea contains structures that convert mechanical vibrations into neural signals

Vestibular nerve (eight cranial nerve) and cochlear nerve

Semicircular canals- lateral and anterior

Auditory/cochlear nerve- carries hearing information from the cochlea towards the brain (cochlea to the cochlear nerve to the brain)

dB SPL

Decibels Sound Pressure Level;

physical sound level measurement

calibrated in sound level meter devices.

20 Pa in air

Measures sound physically

Doesn’t use the audiogram/audiometer

For 0dB, reference physical pressure

For the higher number, more physical sound pressure

dB HL

Decibels Hearing Level (hearing sensitivity)

Average normal hearing threshold (measures hearing thresholds)

used in audiometers to compare a person's hearing threshold against a standardized reference for normal hearing.

Approx normal hearing threshold

Tells us how a person’s hearing threshold compares with a standardized reference for normal hearing

More sound needed to hear = poorer sensitivity

0dB HL does not mean silence

20 Pa

Standardized normal hearing reference

Air-Conduction Pathway

Sound pathway passing through the entire auditory system (outer/middle ear): tested by air conduction (testes the entire hearing pathway where the instrument is held in front of ear and moves through the air into the ear and conducted towards the brain)

Gives us the degree of hearing loss (diagnostic value)

• air makes the tympanic membrane vibrate

• The MIS move

• Cochlea gets stimulated

Bone-Conduction Pathway

Directly stimulates the cochlea of inner ear through the mastoid bone

Bypasses outer/middle ear

Tested by bone conduction (a bone oscillator is placed against the skull and sound wave vibrations travels through the skull to the cochlea /to the auditory nerve to the brain)

Gives us type of hearing loss

directly stimulates the cochlea through the mastoid bone bypasses outer and middle and goes to the cochlea

Physical characteristics

Intensity and frequency

• things you physically measure

Physical strength or amplitude of sound pressure

Physical rate of vibration

Psychoacoustic characteristics

Loudness and pitch

• how we perceive a sound

The subjective psychological of frequency and intensity

What is sound?

Generated by pressure wave vibrations carried through medium of air

What are pressure wave vibrations consisted of what alternating phases?

Compressions (high pressure) and rare fractions (low pressure)

These are referred as sinusoids

Frequency

Hertz- Hz

Number of times per second a cycle occurs measured in units of cycles per second or waves per second

Related to pitch

Higher frequency- ?

higher pitch

Low frequency- ?

low pitch

Intensity

Unit- decibels dB

The amount of sound energy per unit of area

A physical characteristic of sound

Loudness

Unit- Phons

The subjective experience as contrasted with the purely physical force of intensity.

The perception of intensity

What is Amplitude?

• How large or tall a wave is. The height/size of the wave.

The maximum displacement moved on a sound wave measured from its point of equilibrium. (Resting/middle position)

Relates to intensity/loudness

DOESN’T DETERMINE PITCH

Bigger amplitude =?

Greater intensity and generally perceived as louder

Smaller amplitude=?

Lower intensity and perceived as softer

Wavelength

The distance from one point on a wave to the same point on the next cycle.

Peak to peak

Phase

where the wave is in its cycle.

The relationship in time between two tones of the same frequency,

Time

How the wave changes over time

What is the Weber Test

When you strike a tuning fork, the sound moves to both ears and should be heard equally (localization)

If the patient has sensorineural hearing loss, they won’t hear it in the ear that has sensorineural hearing loss which means it localizes the good ear

Example- if your right ear can’t hear it, it’s the sensorineural one and your left ear is the good one.

How is the Weber Test performed?

Place the base of a struck tuning fork on the bridge (midline) forehead, nose or teeth. (Can be activated by flicking it between your fingers or tapping your knee)

Always important to explain the test clearly to the patient and how it’s done

If there is no lateralization (sound coming from a specific direction) of sound in a normal test-

(Weber Test Results)

sound is heard in both ears and normal hearing

If there is unilateral conductive loss, ?

(Weber Test Results)

Sound lateralizes towards the affected (bad) ear

If there is unilateral sensorineural loss, ?

(Weber Test Results)

Sound lateralizes to the better hearing ear

What is the Rinne Test

What position the ear is louder in

Position A- air or position b- bone

• comparing which one air/bone the patient can hear louder/longer

Explain how the test is done

Purpose- help determine whether there could be a conductive hearing loss

How is the rinne test performed?

placing the fork on the mastoid bone and then beside the auditory canal (ear canal)

The patient will indicate when the sound is no longer heard (if they hear it)

AC- tuning fork should always be held PERPENDICULAR to the external unit chatis. NEVER PLACE IT PARALLEL.

Positive Rinne Test Result?

The patient is able to hear the tuning fork after bone conduction fades

air conduction is heard longer or better than bone conduction (AC > BC)- the patient will hear the fork at the ear than the bone)

Normal hearing - AC>BC

Negative Rinne Result

conductive hearing loss where bone conduction is heard better than air conduction (BC > AC)- patient won’t hear the fork at the ear and the person should be able to hear the tuning fork through the bone.

Conductive- BC>AC

Threshold of Audibility

The softest or quietest sound a person can detect with normal hearing in a quiet environment under specific conditions.

The threshold varies depending on:

Measured in decibels

0 dB (decibels)

represents the average normal threshold for a pure tone. Adults would

normally have a normal hearing threshold up to 25 dB while children are up to

15dB or lower.

Human ears aren’t equally sensitive to all pitches

Sensitivity is highest between _____ and ___ where the threshold candrop below 0dB SPL

2000hZ and 5000hZ where the threshold candrop below 0dB SPL

Testing conditions- pure tone audiometer raising and lowering sound volume

in 5dB to find exact point of detection.

Humans are generally most sensitive to frequencies around the range important

for speech.

ANSI

American National Standards Institute;

an organization established to oversee the creation and use of guidelines that affect all centers of U.S. business. Includes acoustical devices like audiometers, construction equipment and etc. Also involved in accreditation of variety of programs.

ASHA

American Speech-Language and Hearing Association;

a professional organization representing speech, language, and hearing sciences professionals.

Equal Loudness Contour

describes how the subjective perception of loudness varies across frequencies and sound pressure levels.

Same dB doesn’t sound equally loud at every frequency

The graph consists of 13 contour curves of equal loudness, measured in phons,

from 0 phons to 120 phons in increments of ten. The curves are all roughly the

same shape, starting near each other at low frequency, decreasing and then

leveling out at middle frequencies, with a minimum for each curve at about 5000

hertz. The curves then rise irregularly toward higher frequencies.

A low-frequency sound may need to have more physical intensity than a mid-frequency sound for you to perceive both as equally loud.

Equal Loudness Contour (Graph outline)

The curves represent equal loudness as perceived by the average human ear (upper curves)

• Equal loudness in phons (loudness in phons)

• The ears is less sensitive to low frequencies and discrimination against lows gets steeper for softer

sounds (the middle)

• The maximum sensitivity region for human hearing is around 3-4kHz and is associated with the

resonance of the auditory canal (the lower)

• Curve for the average threshold of hearing (dotted curve line)

• Sound intensity in decibels doesn’t directly reflect the changes in the ear’s sensitivity with

frequency and with sound level (y-axis)

Audibility Curve

Standardized graph showing the quietest sound pressure level an average human ear can hear across different frequencies

Can show the limits of what humans can hear across different frequencies and intensities

Shows-

Frequencies humans can hear

How sensitive is at different frequencies

Minimum sound level needed to hear different frequencies

Characteristics of a Decibel

1. It involves a ratio

2. It utilizes a logarithm

3. Nonlinear

4. Expressed various reference levels where its specified

5. A relative unit of measure

a logarithmic unit used to express a ratio between two lengthy numbers of sound level/intensity/pressure

Cross Section of Cochlea

Anatomical structure showing the scala vestibuli, scala media, scala tympani, organ of Corti, tectorial membrane, basilar membrane, hair cells, and auditory nerve. Also inner hair cells and outer hair cells.