Week 6 Vocabulary

Question 1

Congenital Deafness

Answer 1

Hearing loss from birth.

Question 2

Sign Language

Answer 2

A type of communication that relies on manual gestures and body language. This type of language is often used by individuals who are deaf or those who cannot speak.

Question 3

Pinna

Answer 3

The anatomical term for the outer ear.

Question 4

Tympanic Membrane

Answer 4

The anatomical term for the ear drum. Sound waves that enter the ear cause vibrations of the ear drum.

Question 5

Ossicles

Answer 5

The bones of the middle ear. They are the malleus that is connected to the tympanic membrane, the incus, and the stapes that pounds on the oval window of the cochlea.

Question 6

Cochlea

Answer 6

The organ of the inner ear containing sensory cells responsible for transducing sound waves into neural impulses that are sent to the brain through the vestibulocochlear nerve (Cranial Nerve VIII).

Question 7

Spiral Ganglion

Answer 7

The group of neuronal cell bodies that send information on sound to the brain. They receive their information from the inner hair cells of the cochlea.

Question 8

Cerumen

Answer 8

A fancy name for ear wax.

Question 9

Acceleration

Answer 9

The rate of change in velocity (speed) over time. This is what is sensed by our vestibulum.

Question 10

Linear Acceleration

Answer 10

Acceleration in one direction (i.e. up, down, forward, backward, etc). An important linear acceleration for balance is the force of gravity.

Question 11

Disequilibrium

Answer 11

This occurs when our ability to detect linear acceleration is impaired. This is the feeling of being off-balance.

Question 12

Angular Acceleration

Answer 12

The force we feel when our body or head turns in a circle. Examples would when you hold your friends’ hands and spin quickly in a circle.

Question 13

Vertigo

Answer 13

Occurs when our ability to detect angular acceleration is impaired. This is the feeling of your head, or the room, spinning.

Question 14

Vestibular System

Answer 14

The sensory system which allows us to balance.

Question 15

Vestibulum

Answer 15

The sensory organ of the vestibular system. It is located in the inner ear and connected to the cochlea, with which it shares a special fluid known as endolymph.

Question 16

Vestibulocochlear Nerve (Cranial Nerve VIII)

Answer 16

The cranial nerve that transmits both sound and balance information to the brain.

Question 17

Endolymph

Answer 17

The fluid that fills the inner ear (the cochlea and the vestibulum).

Question 18

Meniere’s Disease

Answer 18

A disease that affects the endolymph, or fluid of the inner ear. It can present with a combination of hearing impairment, tinitus, and vertigo.

Question 19

Tinitus

Answer 19

Ringing in the ear(s).

Question 20

Schwannoma

Answer 20

A benign tumor of the myelinating cells of the peripheral nervous system, Schwann cells. A common location for this type of tumor is near the vestibulocochlear nerve. This is known as an acoustic neuroma or vestibular schwannoma, and can present with hearing loss, tinitus, or balance problems.

Question 21

Amplitude

Answer 21

In regards to sound, this is the loudness of a sound. Higher amplitude sounds are perceived as being louder.

Question 22

Frequency

Answer 22

In regards to sound, this is the pitch of a sound. Higher frequency sounds are perceived as having a higher pitch.

Question 23

Resonant Frequency

Answer 23

The frequency at which something will naturally vibrate with an increased amplitude. The resonant frequency of the ear canal is in the range of human speech, which leads to an increased amplitude allowing us to better hear human speech relative to other sounds.

Question 24

Impedance Matching

Answer 24

This is the function of the middle ear. It allows sound information to be translated from an airborne medium (external ear) to a fluid medium (inside the cochlea). Importantly, the frequency (or pitch) is maintained in this translation.

Question 25

Oval Window

Answer 25

The membrane that is contacted by the stapes. This leads to a fluid pressure wave within the cochlea that is eventually detected and transducer to a neural impulse. Interestingly, the oval window is smaller than the tympanic membrane, which actually helps in amplifying sound.

Question 26

Tensor Tympani

Answer 26

A muscle that is activated during chewing, which tightens the tympanic membrane. This increases the frequency of sounds that enter the ear, helping us to separate external sounds from the sound of chewing.

Question 27

Stapedius

Answer 27

A muscle that is engaged in response to loud sounds. This pulls back on the stapes to dampen its impact on the oval window. This is a protective mechanism to minimize damage to the hair cells of the cochlea.

Question 28

Hyperacusis

Answer 28

A condition where someone is very sensitive to sound. It may be caused by an impairment of the stapedius muscle, which would affect our ability to dampen loud sounds.

Question 29

Round Window

Answer 29

The second flexible membrane of the cochlea (the first being the oval window). Once the stapes hits the oval window, fluid moves in a wave through the cochlea. Without the round window, this fluid would hit an immovable end, resulting in a reduced ability to hear.

Question 30

Tonotopy

Answer 30

The distribution of frequency-responsive segments of the cochlea. Higher frequencies are detected at the base of the cochlea, and lower frequencies are detected at the apex of the cochlea.

Question 31

Cochlear Duct

Answer 31

The portion of the cochlea that contains the frequency-responsive membrane and the hair cells embedded within it.

Question 32

Cochlear Amplifier

Answer 32

This is the mechanism by which the cochlea allows us to distinguish extremely close frequencies. It is reliant on the membrane of the cochlear duct and the outer hair cells embedded within it. Different portions of the membrane have different resonant frequencies, which promotes outer hair cell motility in response to specific frequencies. This outer hair cell amplification of sound stimulates the inner hair cells, which supports frequency resolution.

Question 33

Outer Hair Cell

Answer 33

Motile cells of the cochlear duct that are innervated by the brain. They are a key cell for the close frequency resolution of the cochlea.

Question 34

Inner Hair Cell

Answer 34

Sensory cells of the cochlea that synapse with spiral ganglion neurons.

Question 35

Otoacoustic Emissions

Answer 35

Sounds generated by the inner ear in response to external sound. Used by doctors to diagnose hearing problems in babies who cannot signal to us that they cannot hear. Otoacoustic emission will only be heard if the external, middle, and inner ear are properly functioning.

Question 36

Presbycusis

Answer 36

Age-related hearing loss. This is due to the slow and gradual death of outer hair cells in response to loud sounds over time. High frequency hearing is the first to be affected.

Question 37

Conductive Hearing Loss

Answer 37

A hearing deficit due to a problem getting sound to the cochlea. This could be due to a build-up of cerumen, damage to the tympanic membrane, a middle ear infection, or otosclerosis. This can be detected with the Rinne test as sound being louder via bone conduction than air conduction.

Question 38

Sensorineural Hearing Loss

Answer 38

A hearing deficit due to a problem in the cochlea or neural transmission of sound. This type of hearing loss in one ear can be detected by the Weber test, which will present as the sound being louder in the impaired ear. The sound appears louder in the impaired ear because of the reduction in background noise detected by the impaired ear.

Question 39

Rinne Test

Answer 39

A hearing test performed by placing a tuning fork on the bone behind the ear, and then next to the ear. This test is useful for detecting conductive hearing loss, which presents with air-conducted sound as quieter than bone-conducted sound. It cannot detect sensorineural hearing loss.

Question 40

Weber Test

Answer 40

A hearing test performed by placing a tuning fork in the middle of the head, using only bone-conducted hearing. Normally, the sound will be equally loud in both ears. If a patient has sensorineural hearing loss in one ear, they will perceive the sound as louder in the healthy ear. If a patient has conductive hearing loss in one ear, they will perceive the sound as louder in the affected ear. This is because of the reduction in background noise detected by the ear with conductive hearing loss.

Question 41

Hearing Aid

Answer 41

A device that acts to amplify sound to improve the ability to hear. It specifically amplifies high frequency sounds, which are generally the first sounds lost in presbycusis.

Question 42

Cochlear Implant

Answer 42

A device that is implanted and can stimulate a few portions of the cochlea in response to sound. This device bypasses the external and middle ears.

Question 43

Prestin

Answer 43

A protein that acts as the molecular motor in outer hair cells.

Question 44

Otoferlin

Answer 44

An important component of the synapse between inner hair cells and spiral ganglion cells.

Question 45

Tectorial Membrane

Answer 45

The membrane within the cochlear duct in which outer hair cells are embedded.

Question 46

Usher Syndrome

Answer 46

A group of genetic disorders that cause deafness, vertigo, disequilibrium, and blindness. Although relatively rare, they are responsible for the majority of cases of deaf-blindness.

Question 47

Semantics

Answer 47

The meaning of the words and phrases we use in speech

Question 48

Prosody

Answer 48

This is the intonation placed on the words and phrases used in speech. We derive most of the meaning of what we say and hear from prosody. In fact, other animals can understand prosody, but pay no attention to semantics.