PNB Exam 4 Pt 2

conductive deafness

damage to middle or external ear (impairs all sound frequencies)

What happens when the stereocilia bend towards the kinocilium?

depolarization because K+ and Ca+ are allowed in

medial superior olive function

detectable time difference

tonotopic auditory cortex

different regions of your cortex respond to differing frequencies

Endocrine gland releases

effector hormones

sound coming in at 500 Hz with an intensity of 50 decibels vs sound coming in at 500 Hz with 150 decibels, coded

encoded at same location on cochlea, but action potentials change

cochlea filled with which liquids

endolymph (in Scala media) and paralymph (in scala vestibuli and scala tympani)

Goiter is caused from what?

enlargement of thyroid often due to over-secretion of TSH

when the stereocilia are displaced towards the kinocilium, what happens

hair cell depolarizes due to K and Ca influx

tonotopic definition

hair cells vary in their response to tone

when basilar membrane vibrates, what happens

hair cells vibrate and hit the tectorial membrane

endolymph, which surrounds ________, has really high _____ which allows for _____ to flow ____ to____

hair cells, K, K, out, in

Close to oval/round window is high or low frequency?

high

thicker part of the cochlea is high or low pitch

high

What's special about the endolymph?

high potassium low sodium

What happens when the stereocilia bend away from the kinocilium

hyperpolarization because no K+ and Ca+ come in

releasing hormone released from where

hypothalamus

is the stiff region of the cochlea near the round window or the apex? is it high or low pitch?

round window, high pitch

sound comes in at ________, high/low frequency pitch sounds.

round window, high,

sounds come out of cochlea via

scala tympani

sounds come into cochlea via

scala vestibular

cochlear hair cells are only located in the _______ media, with ______ K and ______ Na

scala, high, low

Goiter caused from which thyroidism

secondary hyperthyroidism because of overproduction of TSH or primary hypothyroidism which is not enough T3 and T4

Cretinism symptoms

short, disproportionate body, mental retardation

outer hair cells

shorten when depolarized, they increase amplitude and clarity of sound

scala media (endolymph) have extremely low concentrations of __________ and high concentrations of ___________

sodium, potassium

inner hair cell rests at ______ and endolymph rests at _______

-45, 80

an individual is perceiving two different sounds, one is 150 Hz and one is 1020 Hz. 1020 is perceived in cochlea where, 150 is perceived where

1020 is perceived at oval window, 150 perceived at apex

100 Hz or 1600 Hz sound is closer to the oval window?

1600 Hz

What is endolymph potential and perilymph potential and inner hair cell potential

80, 0, -45

organ of corti is located where?

cochlear duct/scala media

How does iodine enter the cell?

Na/I cotransporter

TSH purpose

TSH receptor activation stimulates all steps of thyroid hormone synthesis

primary nerves in ear synapse with second order where

cochlear nuclei

P blob

color

does damage to the middle ear (conductive deafness) harm all frequencies equally or specific frequencies?

all

Is amine, peptide, steroid hormone water or lipid soluble

amine is water, peptide is water, steroid is lipid

function of middle ear

amplify sound

stimulating hormone released from

anterior pituitary

inferior colliculi function

auditory reflexes

sound vibrates _______ which causes stereocilium to push against ________

basilar membrane, tectoral membrane

what changes from oval window to apex

basillar membrane thickness, not hair cells

What is Graves' disease?

body produces TSI which mimics TSH, symptoms of hyperthyroidism

organ of court located in _______ which is filled with fluid that has abnormally high ______

cochlear duct (scala media), K

when ______ enters stereocilia after the depolarization occurs, this leads to release of _______, triggers the ________ which transmits auditory information

calcium, neurotransmitter, cochlear nerve

function of the external ear

channel sound into the ear

if there's no vibration pushing the stereocilia into the tectoral membrane, gated ion channels are ______, K is/is not entering, membrane is ________

closed, is not, hyperpolarized

Anterolateral pathway sensations

coarse touch, temperature, pain

Where is endolymph located?

cochlea duct

if you have sensorineural deafness, you're damaging cells closer to the ________

cochlear base

two types of deafness

conductive deafness to middle or external ear (impairs all sound frequencies) and sensorineural which is damage to inner ear hair cells and impairs ability to hear some pitches more than others

What would happen with no middle ear

conductive deafness, can't take sound waves coming in and transmit them

superior olive is where what comes together, what is main function

convergence of both sides, sound localization

sensorineural deafness

damage to inner ear hair cells and impairs ability to hear some pitches more than others

Dorsal pathway sensations

fine touch, proprioception, vibration

cochlea is air or fluid filled?

fluid

P-interblob

form and depth

cochlear apex, low or high frequency

furthest, low frequency

if an individual has a mutation where their endolymph inside the Scala media is replaced with paralymph what happens following stereocilia bending towards kinocilia?

in paralymph, K concentration is low (mimics normal CSF/ESF), you wouldn't have extracellular K to enter, depolarization wouldn't occur when stereocilium are activated, wouldn't allow Ca to enter which means no NT released and no signal to auditory cortex

when the vibration pushes the stereocilia against the tectoral membrane into the kinocilia, gated ion channels are ______, K is/is not entering, membrane is _______

open, is, depolarized

Ending of amine hormones

ine and in

what is the primary sensory receptor of the ear

inner hair cells

frequency of action potentials increases is which type of coding

intensity coding

potassium flows _______ the hair cells because they rest at _______

into, -45

potassium flows ______ the hair cells and sodium flows ______ in the endolymph

into, out of

Enzymes add _______ to ________ to make __________ and _________

iodine, tyrosine, T3 and T4

Ending of steroid hormones

iol or one

What happens with Gs? (3)

ion channel activity via CNGs, gene transcription via CREs, phosphorylation via activation of protein kinase A

stereocilium on the hair cells which are graduated in size. largest one is ________. when they're pushed against the _______ from vibration of the basilar membrane, the stereo cilium bend towards the ________, which causes ________ gated _____ channels to open/close, ______ flows in/out hyperpolarizing/depolarizing membrane causing _______ gated _______ channels to open/close, ______ enters, and triggers vesicles to migrate towards active zone releasing _________ and activating ____________

kinocilium, tectoral membrane, kinocilium, mechanically, potassium, open, K, in, depolarizing, voltage, calcium, open, calcium, neurotransmitters, auditory neurons

Goiter is caused by excess or lack of iodine?

lack of iodine

lateral or medial superior olive is for frequencies above 3000 Hz

lateral

Is thyroxine (T3 & T4) lipid or water soluble

lipid

lipid or water soluble needs a carrier in the blood?

lipid needs a carrier

intensity coding key point

louder sound (higher amplitude) produces more action potentials

lateral superior olive function

loudness difference

Hypothyroidism (myxedema) symptoms

low BMR, feel "chilled", edema, lethargy, mental sluggishness

At the apex of the unrolled cochlea, is that high or low frequency?

low frequency

gate of ion channels in the stereocilia

mechanically gated

is lateral or medial superior olive for frequencies below 3000 Hz

medial

individual is presenting some sort of deafness. they can't hear anything - doesn't matter pitch or frequency - everything is muffled, this is damage to ______ and called _______

middle ear, conductive deafness

if you're extremely intense in the amplitude of sound waves coming iim you generate more/less action potentials

more

M pathway

movement

function of tympanic membrane

multiple muscles contract to protect middle ear and cochlea with loud sounds

Can water soluble hormones cross through the membrane

no

Do water soluble hormones need a transporter in the blood?

no

damage before superior olive is ok or no

no

do water soluble hormones need a transporter in the blood?

no

is damage of one side of the auditory cortex bad

no

When stereocilia bend away from kinocilium, lots of/no potassium enters, membrane is hyperpolarized/depolarized

no, hyper polarized

medial geniculate nucleus

part of the thalamus that filters and relays auditory information

Damage to V4 affects

perception of color

frequency and _____ are the same

pitch

frequency coding is based off of

pitch

activating hair cells is caused from shear force which opens _____ channels, when you're not hearing/no vibrations, there's no shear force so stereocilia are/are not pushing against kinocilium

potassium, are not

scala vestibuli and scala tympani (perilymph) have extremely low concentrations of __________ and high concentrations of ___________

potassium, sodium

inner hair cells

primary sensory receptors

Hypothalamus releases _______

releasing hormone

superior olive function

sound localization

______ opens potassium channels, _______ opens calcium channels

stress, voltage

once you get to _______, damage to one side won't matter so much in auditory system

superior olive

auditory cortex is tonotropic, what else is tonotropic?

the cochlea, interprets various frequencies at various locations

low frequency is sensed by thick end or thin end? near oval window or near apex?

thin, apex

Amine hormones

thyroxine (T3. T4), epinephrine, norepinephrine, dopamine, melatonin

hair cells are organized _____

tonotopically, hair cells are organized by tone

Anterior pituitary releases ________

tropic hormone

Ca channels are ________ gated in stereocilia

voltage gated

ADH function

water conservation

water or fat soluble hormones activate cAMP

water soluble

Do lipid soluble hormones need a transporter in the blood?

yes

is the auditory cortex plastic?

yes