PSYC 230 UIUC EXAM 2025 QUESTIONS WITH ANSWERS
GUARANTEE A+
✔✔Stapes (stirrups) - ✔✔Vibrates against oval window creating pressure waves leading
to transduction by hair cells on basilar membrane in cochlea
✔✔Inner ear - ✔✔functions: transduce sound into a neural signal
✔✔Cochlea - ✔✔Snail-shaped structure of the inner ear that houses the hair cells that
transduce sound into a neural signal.
✔✔Tympanic canal - ✔✔One of three fluid-filled chambers in the cochlea. Vibrations
travel down it.
✔✔Middle canal - ✔✔One of three fluid-filled passages in the cochlea. In between the
tympanic and vestibular canals.
✔✔Vestibular canal - ✔✔One of the 3 fluid filled chambers of the Cochlea. Vibrations
travel down it, but not the tympanic canal.
✔✔Reissner's membrane - ✔✔A thin sheath of tissue separating the vestibular and
middle canals in the cochlea.
✔✔Basilar membrane - ✔✔Composed of fibers, like the base that contains the very
important cells involved in transduction. Contains the organ of corti.
✔✔Tectorial membrane - ✔✔a gelatinous flap, attached on one end, that extends into
the middle canal of the ear
✔✔Organ of corti - ✔✔Center part of the cochlea, containing hair cells, canals, and
membranes
✔✔Hair cells - ✔✔receptor cells for hearing found in the cochlea
✔✔Stereocilia - ✔✔hairlike extensions on the tips of hair cells in the cochlea that initiate
the release of neurotransmitters when they are flexed
✔✔Inner hair cells - ✔✔Convey almost all info about sound waves to the brain
✔✔Outer hair cells - ✔✔Receive information from the brain (using efferent fibers). When
they're stiffer, can help surpress noise and when less stiff, can help tune to a given
frequency.
, ✔✔Small amplitude sounds - ✔✔Small displacements along the cochlea, the tectorial
membrane will shear across the organ of corti less forcefully, and hair cells will bend to
a smaller degree.
✔✔Large amplitude sounds - ✔✔Large displacements along the cochlea. Tectorial
membrane will shear across the organ of corti more forcefully, hair cells will bend to a
large degree.
✔✔How and where is frequency coded? - ✔✔Frequency is coded along the basilar
membrane through different amounts of displacement
✔✔Place code theory - ✔✔Different locations along the basilar membrane respond to
different frequencies. A sound of a particular frequency will maximally displace the
basilar membrane at a specific location.
✔✔Characteristic frequency - ✔✔The frequency to which any particular location on the
basilar membrane responds best.
✔✔Temporal code theory - ✔✔Frequency representation occurs because of a match
between sound frequency and the firing rates of the auditory nerve. For example, if the
nerve fires 500 times in a second, that equals 500 Hz.
✔✔tuning curve for an auditory nerve fiber - ✔✔1. Find the lowest point on the curve
2. Read the frequency (kHz = Hz x 1000)
3. In this example, this neuron responds very strongly to a 10,000 Hz frequency(when
the sound is very faint)
4. This neuron's response will signal the brain that the frequency of the sound is 10,000
Hz
5. This is the neuron's characteristic frequency
6. The rest of the red curve has higher values on the Y-axis, meaning that higher
intensities of sounds are needed to observe a response higher than baseline from that
neuron
✔✔Brain anatomy and the pathway of hearing - ✔✔Auditory nerve fibers make the 8
cranial nerves.
✔✔Function of cochlear nucleus - ✔✔Serves as a lateral inhibition function (sharpen a
particular frequency by inhibiting the response to nearby frequencies.
✔✔Function of trapezoid body - ✔✔Important for determining the direction of sound.
✔✔Function of superior olive - ✔✔Receives information from both ears, critical for
sound localization.
✔✔Inferior colliculus - ✔✔a midbrain nucleus in the auditory pathway
GUARANTEE A+
✔✔Stapes (stirrups) - ✔✔Vibrates against oval window creating pressure waves leading
to transduction by hair cells on basilar membrane in cochlea
✔✔Inner ear - ✔✔functions: transduce sound into a neural signal
✔✔Cochlea - ✔✔Snail-shaped structure of the inner ear that houses the hair cells that
transduce sound into a neural signal.
✔✔Tympanic canal - ✔✔One of three fluid-filled chambers in the cochlea. Vibrations
travel down it.
✔✔Middle canal - ✔✔One of three fluid-filled passages in the cochlea. In between the
tympanic and vestibular canals.
✔✔Vestibular canal - ✔✔One of the 3 fluid filled chambers of the Cochlea. Vibrations
travel down it, but not the tympanic canal.
✔✔Reissner's membrane - ✔✔A thin sheath of tissue separating the vestibular and
middle canals in the cochlea.
✔✔Basilar membrane - ✔✔Composed of fibers, like the base that contains the very
important cells involved in transduction. Contains the organ of corti.
✔✔Tectorial membrane - ✔✔a gelatinous flap, attached on one end, that extends into
the middle canal of the ear
✔✔Organ of corti - ✔✔Center part of the cochlea, containing hair cells, canals, and
membranes
✔✔Hair cells - ✔✔receptor cells for hearing found in the cochlea
✔✔Stereocilia - ✔✔hairlike extensions on the tips of hair cells in the cochlea that initiate
the release of neurotransmitters when they are flexed
✔✔Inner hair cells - ✔✔Convey almost all info about sound waves to the brain
✔✔Outer hair cells - ✔✔Receive information from the brain (using efferent fibers). When
they're stiffer, can help surpress noise and when less stiff, can help tune to a given
frequency.
, ✔✔Small amplitude sounds - ✔✔Small displacements along the cochlea, the tectorial
membrane will shear across the organ of corti less forcefully, and hair cells will bend to
a smaller degree.
✔✔Large amplitude sounds - ✔✔Large displacements along the cochlea. Tectorial
membrane will shear across the organ of corti more forcefully, hair cells will bend to a
large degree.
✔✔How and where is frequency coded? - ✔✔Frequency is coded along the basilar
membrane through different amounts of displacement
✔✔Place code theory - ✔✔Different locations along the basilar membrane respond to
different frequencies. A sound of a particular frequency will maximally displace the
basilar membrane at a specific location.
✔✔Characteristic frequency - ✔✔The frequency to which any particular location on the
basilar membrane responds best.
✔✔Temporal code theory - ✔✔Frequency representation occurs because of a match
between sound frequency and the firing rates of the auditory nerve. For example, if the
nerve fires 500 times in a second, that equals 500 Hz.
✔✔tuning curve for an auditory nerve fiber - ✔✔1. Find the lowest point on the curve
2. Read the frequency (kHz = Hz x 1000)
3. In this example, this neuron responds very strongly to a 10,000 Hz frequency(when
the sound is very faint)
4. This neuron's response will signal the brain that the frequency of the sound is 10,000
Hz
5. This is the neuron's characteristic frequency
6. The rest of the red curve has higher values on the Y-axis, meaning that higher
intensities of sounds are needed to observe a response higher than baseline from that
neuron
✔✔Brain anatomy and the pathway of hearing - ✔✔Auditory nerve fibers make the 8
cranial nerves.
✔✔Function of cochlear nucleus - ✔✔Serves as a lateral inhibition function (sharpen a
particular frequency by inhibiting the response to nearby frequencies.
✔✔Function of trapezoid body - ✔✔Important for determining the direction of sound.
✔✔Function of superior olive - ✔✔Receives information from both ears, critical for
sound localization.
✔✔Inferior colliculus - ✔✔a midbrain nucleus in the auditory pathway
