4A: Auditory Disorders

Question 1

Sound pressure wave

Answer 1

Sound is a mechanical wave that results from the back and fourth vibration of the particles of the medium through which the sound wave a moving.

Question 2

frequency

Answer 2

low to high are associated with increases in the perceptual experience of pitch

Question 3

amplitude

Answer 3

from small to large are associated with increases in the perceptual experiences of loudness

Question 4

Audibility curve

Answer 4

a graph that depicts the relationship between the loudness of a pure tone, expressed in decibels, sound pressure level, and the frequency of the tone

Question 5

outer ear

Answer 5

includes the pinna and auditory canal and ends at the tympanic membrane.

Question 6

tympanic membrane

Answer 6

a thin membrane that separates the external ear from the middle ear whose functions is to transmit sound from the air to the ossicles inside the middle ear

Question 7

middle ear

Answer 7

from tympanic membrane to oval window; includes the ossicles and drains out the eustachian tube to the back of the throat

Question 8

ossicles

Answer 8

three smallest bones in the human body. Contained in the middle ear and serve to transmit and amplify sounds from the air to the fluid filled cochlea. The absence of the ossicles would cause moderate to severe hearing loss.

Question 9

malleus

Answer 9

the malleus or hammer is a hammer shaped small bone or ossicle of the middle ear which connects with the incus and is attached to the inner surface of the eardrum

Question 10

incus

Answer 10

the incus is a small bone or ossicle in the middle ear. It connects the malleus to the stapes.

Question 11

Stapes

Answer 11

small bone or ossicle in the middle ear which is attached to the incus and oval window; bottom of the stapes on the oval window is called the footplate.

Question 12

conductive hearing loss

Answer 12

mechanical hearing loss, resulting from blockage in the ear canal, a ruptured eardrum, or restriction of the movement of the tiny bones in the middle ear, which prevents sound vibrations being transferred to the cochlea.

Question 13

Otosclerosis

Answer 13

a form of conductive hearing loss,
a condition in which there is abnormal growth of bone in the middle ear which can result in hearing loss.

Question 14

Inner ear

Answer 14

from the oval window to auditory nerve; includes oval window, round window, cochlea, auditory nerve finers, and the semicircular canals of the vestibular system

Question 15

Cochlea

Answer 15

the coiled and channeled main structure of the inner ear, which contains three fluid filled canals that run along its entire convoluted length; the fluid filled canals are separated by membranes, one of which is the basilar membrane, on which thousands of hair cells are arranged and stimulated by the vibration of the stapes.

Question 16

Basilar membrane

Answer 16

within the cochlea of the inner ear is a stiff structural element that separates two liquid filled tubes that run along the coil of the cochlea, forming a base for the hair cells to transduce the sound waves in the cochlear fluid to electrochemical signals in the brain

Question 17

tonotopic organization

Answer 17

each section of the basilar membrane responds to a preferential frequency and the sections are organized from high to low

Question 18

inner hair cells

Answer 18

the sensory receptors of the auditory system located on the basilar membrane in the cochlea that convert sound waves to nerve signals by having their hair like stereocilia being physically moved by sounds waves in the cochlear fluid

Question 19

tectorial membrane

Answer 19

moves back and fourth with each cycle of sound, tilting the cilia and allowing electric current into the hair cell

Question 20

Stereocilia and Kinocilium

Answer 20

stereocilia are projections at the top of the hair cell that are attached to one another by structures which link the tips of one cilium to another
-kinocilium is one larger, more stable cilium to which the stereocilium attach the tips

Question 21

outer hair cells

Answer 21

hair like cells on basilar membrane that are involved in amplifying sounds and improving frequency selectivity

Question 22

organ of corti

Answer 22

organ in the inner ear of mammals that contains the hair cells

Question 23

sensorineural hearing loss

Answer 23

hearing loss caused by damage to the sensory cells and/or nerve fibers of the vestibulocochlear nerve, inner ear, or central processing centers of the brain

Question 24

cochlear implant

Answer 24

surgically implanted electronic device that provides sense of sound to a person who is profoundly deaf or severely hard of hearing. Most commonly, a cochlear implant is used when the hair cells of the patient are damaged with a genetic abnormally affecting action potentials.

Question 25

cochlear nucleus

Answer 25

a group of cell bodies in the lower section of the brainstem that receives the input from the auditory nerve fibers coming from the cochlea

Question 26

superior olive

Answer 26

a small group of cell bodies in the middle section of the brainstem involved in the localization of sound by determining differences in the timing and intensity level of neural responses from each ear for a particular sound

Question 27

medial superior olive

Answer 27

interaural time difference- the time difference of arrival of sounds between the ears

Question 28

lateral superior olive

Answer 28

interaural level difference- the difference of the intensity level of sounds between the ears

Question 29

Inferior colliculus

Answer 29

located just below the visual processing centers known as the superior colliculus. it contains neurons that are tonotopically organized and it likely integrated information regarding sound localization

Question 30

Medial geniculate nucleus

Answer 30

section of the thalamus that the auditory pathway connects through prior to reaching primary auditory cortex

Question 31

lateral sulcus

Answer 31

the lateral sulcus is the sulcus that divides the frontal and temporal lobes of the brain

Question 32

Primary auditory cortex

Answer 32

located within the lateral sulcus
-the main area of cortex which first processes auditory information in the brain, situated on the inferior surface of the lateral sulcus; contains core, belt, and parabelt subdivisions

Question 33

Superior temporal gyrus

Answer 33

the most superior gyrus in the temporal lobe, situated just below the lateral sulcus, on which is much of auditory cortex

Question 34

superior temporal sulcus

Answer 34

the most superior sulcus on the temporal lobe, situated just below the superior temporal gyrus

Question 35

tonotopy

Answer 35

is a cortical map of sound frequency (single tones)

Question 36

periodotopy

Answer 36

is a cortical map of sound time duration (periodicity)

Question 37

Cortical deafness

Answer 37

a rare form of sensorineural hearing loss caused by bilateral cortical lesions in the primary auditory cortex located in the temporal lobes of the brain. Patient is unable to hear sounds but has no apparent damage to the anatomy of the ear, which can be thought of as the combination of auditory verbal agnosia and auditory agnosia.

Question 38

Auditory agnosia

Answer 38

a rare form of agnosia that manifests itself primarily on the inability to recognize or differentiate between sounds. It is not a defect of the ear or hearing but rather a neurological inability of the brain to process sound meaning.

Question 39

Pure word deafness

Answer 39

the selective inability to comprehend the spoken word, in the absence of aphasia or defective basic hearing. Perception of environmental sounds and other complex, non-speech sounds is generally normal. Pure word deafness is caused by bilateral damage to temporal lobes

Question 40

non verbal auditory agnosia

Answer 40

selective impairment in nonverbal auditory comprehension, in the absence of verbal comprehension deficits, other aphasias, or defective basic hearing; may arise from lesions in/near Wernicke’s area

Question 41

Amusia

Answer 41

the selective inability to recognize musical tones or to reproduce them. Amusia can be congenital (at birth) or acquired sometime later in life (from brain damage)

Question 42

Word meaning deafness

Answer 42

a comprehension deficit specific to the auditory modality; written comprehension is impaired.