Hearing, Ear Anatomy, and Auditory Disorders

Vocabulary practice flashcards covering ear anatomy, the physiology of hearing, common auditory pathologies, and hearing assistive technologies.

Audiologist

A healthcare professional who specializes in the treatment and evaluation of patients with hearing loss and related auditory disorders.

Pitch

A perceptual characteristic of sound determined by frequency, or how rapidly sound waves vibrate each second, measured in Hertz ($\text{Hz}$).

Sound Intensity

The amount of energy in a sound wave, determined by its amplitude and commonly referred to as loudness.

Outer Ear

The visible external region of the ear, comprising the pinna and external auditory canal, responsible for collecting and funneling sound waves toward the tympanic membrane.

Pinna

The only visible outer structure of the ear; shaped like a funnel to assist in capturing and directing sound waves into the external auditory canal.

Tympanic Membrane

A thin layer of tissue—also called the eardrum—that vibrates when struck by sound waves from the outer ear and transmits those vibrations to the ossicles.

Middle Ear

The air-filled cavity extending from the tympanic membrane to the oval window that receives sound waves from the outer ear and converts them into mechanical vibrations.

Ossicles

A chain of three tiny bones in the middle ear—the malleus (hammer), incus (anvil), and stapes (stirrup)—that form a bridge transmitting vibrations from the eardrum to the oval window.

Malleus

The first ossicle in the middle ear chain, commonly known as the hammer, which connects directly to the tympanic membrane to receive incoming vibrations.

Incus

The intermediate middle ear bone, commonly known as the anvil, positioned between the malleus and the stapes.

Stapes

The innermost ossicle of the middle ear, commonly known as the stirrup, which attaches to the oval window to transfer mechanical vibrations to the inner ear fluid.

Eustachian Tube

A narrow canal connecting the middle ear to the nasopharynx that equalizes air pressure between the middle ear cavity and the outside atmosphere.

Inner Ear

The innermost region of the ear consisting of the vestibule, semicircular canals, and cochlea, responsible for hearing transduction and maintaining equilibrium.

Semicircular Canals

Three tiny, fluid-filled inner ear loops lined with sensory hair cells that detect head movement to help maintain balance and equilibrium.

Cochlea

A snail-shell-shaped organ within the inner ear containing perilymph fluid and approximately $24{,}000$ microscopic hair fibers that convert mechanical vibrations into electrical nerve impulses.

Perilymph

The specialized fluid contained inside the cochlea that transmits mechanical sound vibrations across the partitioned membranes to stimulate auditory hair cells.

Presbycusis

Age-related sensorineural hearing loss caused by the natural aging of the human auditory system, typically affecting mid- to high-frequency sounds.

Meniere's Disease

An inner ear disorder associated with fluid volume changes inside the labyrinth, characterized by episodes of severe vertigo, imbalance, nausea, and low-frequency sensorineural hearing loss.

Labyrinthitis

Inflammation of the inner ear labyrinth, frequently arising after an upper respiratory viral infection, causing vertigo, dizziness, and sensorineural hearing impairment.

Otosclerosis

A hereditary middle ear condition characterized by abnormal spongy bone growth around the ossicles, resulting in progressive conductive hearing loss.

Chronic Otitis Media

Long-term or recurrent inflammation and infection of the middle ear space, often linked to Eustachian tube dysfunction and capable of causing conductive hearing loss.

Tinnitus

The perception of internal ringing, buzzing, or hissing sounds in the ears without an external auditory stimulus.

FM System

A frequency modulation hearing assistive technology where a speaker talks into a microphone transmitter and the listener receives amplified sound through a personal receiver.

Infrared System

An assistive listening system that converts audio into light waves to transmit sound across a room to a compatible receiver, useful for speech comprehension in theaters and TV viewing.

Induction Loop System

An assistive listening setup that broadcasts an audio signal directly into a hearing aid via an electromagnetic field, minimizing ambient background noise.

Completely-in-Canal (CIC) Hearing Aid

A miniature, custom-molded hearing device seated entirely within the ear canal, utilizing the pinna's natural anatomy to direct and amplify sound for mild to moderate hearing loss.

In-the-Ear (ITE) Hearing Aid

A custom-fitted hearing aid housed in a single casing that fills the bowl (concha) of the outer ear, suitable for mild to severe hearing impairments.

Behind-the-Ear (BTE) Hearing Aid

A versatile hearing aid design where the main electronic case hooks over the top of the ear and channels sound through a tube into an earpiece, suited for all ages and hearing loss levels.

Open-Fit Hearing Aid

A behind-the-ear style featuring a narrow tube that leaves the ear canal mostly unblocked, allowing natural entry of low frequencies while amplifying high frequencies.

Cochlear Implant

An electronic medical device surgically placed to bypass damaged cochlear structures and stimulate the auditory nerve directly, designed for severe to profound sensorineural hearing loss.