Hearing Flashcards
True of False?
babies only begin to learn language after birth
False, they learn it before
Cycles per second of sound, perceived as pitch
Hertz (Hz)
Intensity of sound, perceived as loudness
Amplitude
Tone of a single frequency of vibration
Pure tone
Modulated pure tones with repetitions
Musical tone
Noise
Random sounds
Sound waves are distinguished by their _____ and _____
Amplitude
Frequency
What is the amplitude of sound measured in?
Decibels
What is the frequency of sound measured in?
Hertz (Hz)
What is the abbreviation for decibels?
dB
How does the brain decide which noise to ignore?
It determines what is and isn’t useful
Musical tone has a _____ pattern
discernable
Noise has _____ pattern
no
Auditory brain’s first task
discern what is noise and what is not
True or False?
Any complex sound is just simple sine waves added together.
True
Fourier transform analysis
Any complex sound is just simple sine waves added together
Elephants can hear _____ frequencies than humans do
Lower
Cats can hear _____ frequencies than humans do
Higher
Why do elephants hear lower frequencies?
They locate each other through stomps
Why do cats hear high frequencies?
To locate mice at ultrasonic range
True or False?
Mothers can hear frequencies no one else can.
True
Hearing range of humans
20-20,000 Hz
Most sensitive frequencies to human hearing
2,000-5,000 Hz
What are the three main parts of the ear?
Outer ear
Middle ear
Inner ear
What is the outer ear comprised of?
Pinna, ear canal, and tympanic membrane
What is another term for the pinna
Auricle
What is another term for the tympanic membrane
eardrum
What part of the ear is the Pinna in?
Outer ear
What part of the ear is the tympanic membrane in?
Outer ear
What is the middle ear comprised of?
Ossicles-Malleus, Incus, & Staples
What is the inner ear comprised of?
Cochlea and Semicircular canals
What does the external ear and ear canal do?
Collect low frequency sound waves
What connects the tympanic membrane to the oval window?
Ossicles
Why did human ears evolve?
To detect speech
Did vocal cords or auditory receptors of specific frequencies evolve first?
Vocal cords
True or false?
The eardrum is skin pulled over bones
True
Ossicles
Malleus
Incus
Stapes
What do the ossicles do?
Connect the eardrum to the oval window
Smallest bones in the body
Ossicles
The _____ _____ is the window to the cochlea
oval window
_____ muscles in the middle ear move the ossicles
two
When overactivated, muscles _____ to _____ loud sounds
stiffen
dampen
Two muscles in the _____ ear move the ossicles
middle
When the middle ear is overactivated, the bone is _____ ____ from the tympanic membrane
pulled away
Constant overactivation of muscles in middle ear causes _____
damage
What vibrates during step 1 of auditory transduction
air
eardrum
bone
oval window
endolymph fluid
endolymph
fluid inside body
Synonym for auditory nerve synapses in cochlea
cochlear nerve
where stapes meets cochlear duct
oval window
cochlear duct synonym
endolymph
_____ cells lie on the basilar membrane
hair
What are the two types of hair cells on the basilar membrane
inner
outer
What connects inner and outer hair cells
afferent nerve fibers
Where do hair cells lie
basilar membrane
Thin fibers (_____ _____) run across each hair cell’s stereocilia
tip links
Tip links are _____ gated
mechanically
What does it mean for tip links to be mechanically gated?
no graded potentials
hair-like, actin-based protrusions on the surface of sensory hair cells in the inner ear
stereocilia
Sound _____ the stereocilia on auditory hair cells
bends
What happens when the stereocilia on auditory hair cells are bent?
Ca2+ and K+ channels open
Vibration makes stereocilia _____, causing ion channels to _____
bend
open
When hair cells depolarize, there is a _____ influx at the ____ of the cell, resulting in a _____ release
calcium
base
glutamate
What does glutamate release into auditory hair cells cause
Action potential in cochlear nerve
Do hair cells have axons?
no
Do hair cells generate action potentials
no
Change of energy from one type to another
transduction
Bending stereocilia on _____ hair cells causes action potentials in the auditory nerve
inner
EXAM QUESTION
First place in a sound pathway with bilateral input
superior olive nucleus
The superior olive nucleus is the first place in sound pathway with _____ input
bilateral
What is a large reason that we have two ears
determine where sound is coming from
contralateral input determines….
what is it
bilateral input determines….
where it is
Where is the first place sound travels from the cochlea
cochlear nucleus
Where does sound travel after the cochlear nucleus
superior olive
Where does sound travel from the superior olive
inferior coliculus
Where does sound travel from the medial inferior colliculus
medial geniculate body
Where does sound travel from the medial geniculate body
auditory cortex
What is another term for an auditory neuron’s receptive field
preferred frequency
tuning curves
Auditory cells _____ in what frequency they fire to
specialize
True or False?some auditory cells are less picky about the frequency they fire to than others
true
Auditory cells with different preferred frequencies have _____ purposes
different
The auditory cortex is organized by _____
frequency
What is the saying for the frequency organization of the auditory cortex
high in the back
high inside
What is the analogy for the organization of frequencies in the auditory cortex
Party:
highest people are inside the bathroom or in the back passed out
What is frequency coding?
Neurons fire at the same rate as the sound frequency.
What does frequency coding explain?
How we hear low-pitched sounds.
Why can’t one neuron encode high frequencies?
It can’t fire fast enough.
What is the volley principle?
Neurons take turns firing to match high sound frequencies.
How does the volley principle work?
Each neuron fires occasionally, but together they match the sound’s frequency.
When is the volley principle used?
For sounds too fast for single neurons to follow each cycle.
__% of the brain is allocated to frequency coding
10
What is phase locking?
Neurons fire at the same phase of a sound wave.
What frequencies does the volley principle mainly refer to
low frequency
What provides limit in the number of responses for a sound wave
number of neurons
What is the first theory for how we hear pitch
frequency coding
What is the second theory as to how we hear pitch
place coding
What is place coding
each place on basilar membrane has a resonant frequency
in place coding, each place on the _____ membrane has a resonant frequency
basilar
What is the analogy for place coding
tuning a guitar
fat strings on the guitar are (low/high) pitched
low
skinny strings on a guitar are (low/high) pitched
high
Place and volley mechanisms act _____ to code frequency
together
Which theory of how we hear pitch is true for low frequencies
frequency coding
Low frequencies are coded by a frequency of _____ _____
nerve impulses
Which theory of how we hear pitch is true for high frequencies
place coding
High frequencies are coded by ____ along basilar membrane
place
Which theory of how we hear pitch is true for intermediate frequencies
both
Intermediate frequencies are coded through both _____ & _____ mechanisms
frequency
plate
Did we evolve the ability to localize or differentiate sound first?
localize
What are the two differences in the ears
intensity
latency
What is the latency difference between the ears
different arrival times for sounds
Can the brain tell which ear receives a sound first?
yes
What is the intensity difference between ears
different loudness at the two ears
accurate localization requires processing….
both intensity and latency differences
main sound localization nucleus
superior olive
For low frequency sounds, location is coded by _____ differences in the _____ _____
latency
superior olive
What does MSO stand for
medial superior olive
what does the medial superior olive compare
meeting times of sound between ears
The location of high frequency sounds is coded by _____ differences by the _____ _____ _____
intensity
lateral superior olive
Which superior olive compares loudness
lateral
Which superior olive compares meeting times/time difference
medial
The auditory cortex analyzes sounds in _____ streams
two
What are the two streams the auditory cortex uses to analyze sounds?
dorsal
ventral
What is the “Where” pathway of the auditory cortex
dorsal
What is the “What” pathway of the auditory cortex
ventral
Is it possible to shift an auditory cell’s receptive field?
yes
What shifts an auditory cell’s receptive field
learning a new language
Learning to listen to music
learning your baby’s voice
What are the three unconscious systems
sleep
limbic system
hypothalamus
True or False?
We have conscious and unconscious hearing
true
What are the three categories of deafness
conduction
central
sensorineural
disorders of outer or middle ear that prevent sounds from reaching the cochlea
conduction deafness
deafness caused by brain lesions, with complex results
central
Deafness from cochlea or auditory nerve lesions
sensorineural
Central hearing loss is ____
rare
Central hearing loss is associated with _____ _____
neurological disorders
What are the two types of central hearing loss
cortical deafness
Auditory hallucinations
What are the two types of cortical deafness in central hearing loss
pure word deafness
auditory agnosia
Which nervous system does central hearing loss affect?
central
fluent verbal output, impaired spoken language comprehension
pure word deafness
In pure word deafness, nonverbal sounds are _____ identified
correctly
Individuals with auditory agnosia have _____ pure tone hearing
normal
inability to recognize verbal or nonverbal sounds
auditory agnosia
What would an individual have if they cannot recognize a ringing telephone
auditory agnosia
Illusion of complex sound such as music or speech
auditory hallucinations
are auditory hallucinations present in schizophrenia?
yes
Auditory hallucinations may be caused by damage to the _____ _____ _____
second auditory cortex
auditory hallucinations can take place during a _____ _____ seizure
temporal lobe
The 25 year old man’s first symptoms of schizophrenia coincided with ….
breakup of a relationship with a woman
The 25-year old man with schizophrenia heard voices of….
people who were not present or had died
The voices the 25-year old schizophrenic man heart were ____ sentences of _____ directed to him
short
insults
What does SNHL stand for?
sensorineural hearing loss
dysfunction the cells or auditory nerve
sensorineural hearing loss
Individuals with SNHL have inappropriately ____ voices
loud
Individuals with SNHL have speech sounds ____
distorted
Individuals with SNHL struggle with _____ _____ making listening difficult
background noise
Viral infections such as _____ and _____ kill _____ auditory hair cells
measles
CMV
developing
What does NIHL stand for?
noise induced hearing loss
NIHL loss can be _____ or _____
sudden
gradual
What might cause sudden NIHL
explosion
The onset of NIHL is most often a _____ onset that goes _____
gradual
unnoticed
1 preventable cause of deafness
NIHL
__% of rock musicians are partially deaf
37
__% of classical musicians are partially deaf
52
age-related hearing loss
presbycusis
What percent of the population has tinnitus?
10
How many people in the US have tinnitus
40 million
How many people in the US are disabled due to the persistence/intensity of tinnitus
2.5 million
What often triggers tinnitus?
Damage to the cochlea.
What maintains chronic tinnitus?
The central nervous system (CNS).
What do outer hair cells do after hearing loss?
‘Turn up the volume’ via efferent input.
Why do outer hair cells amplify sound after damage
To compensate for inner hair cell loss.
Which brain areas contribute to tinnitus?
Auditory cortex, inferior colliculus, and cochlear nucleus.
