Audition Flashcards
1 Flashcard
As you are clapping to one of you favorite podcasters after they finished their speech, you start to think about how clapping actually make sounds. As you are moving your hands closer towards each other, what is happening to the air molecules in between the two boundaries? What portion of this phenomenon is actually the direct production of clapping sounds?
As you are moving your hands closer to one another the air molecules are compressed due to increased compaction of the molecules. The sound production is a result of pressurized air molecules escaping from your hands as it moves from high to low concentration.
Sounds with bigger distances between the two peaks:
A. Have a greater amplitude
B. Decreased Frequency
C. Smaller Amplitude
D. Higher frequency
B. Decreased or Low Frequency/pitch. Sounds with decreased distances between the two peaks are higher in frequency or higher in pitch
Amplitudes are in regards to high the peaks are. Higher peaks/amplitudes create louder sounds and lower peaks create softer sounds
Are longer frequencies often associated with smaller amplitudes?
Amplitudes and frequencies of a wave are dependent of each other. Due to the physical relationship = Speed of wave (vW) = frequency*wavelength. With this relationship, the speed of sound is almost the same all the time, therefore with larger frequencies, the wavelength is smaller and with smaller frequencies, the amplitude is often larger
cnx.org
In physics there is a saying that long waves travel further. Can this statement be applied within the ear.
Yes, lower and longer waves (lower in frequency sound waves, have to travel further in the cochlea in order to be detected by the hair cells in the basilar membrane. This is due to Basilar Tuning.
After sound waves have past the superior oval window, where is its next destination of travel?
A. To the Ossicles
B. To the Round Window
C. Perilymph
D. To the Tympanic Membrane
C. Perilymph. The vibration from the ossicles are transmitted through the stapes to the perilymph (causing the fluid to move as a result)
The Pinna Funnels sound waves to …
To the external Acoustic meatus or the ear canal
True or false: The Tympanic membrane is directly connected to the malleus, therefore vibration of the eardrum leads to the vibration of the ossicles
True
The motion of fluid in the cochlea is directly related to what physical quantity? What has happened when the perilymph stops flowing?
The motion of the fluid is related to the energy of the sound wave. When the perilymph stops flowing, this means the sound is no longer being produced or the energy of the sound wave has dissipated.
Why doesn’t the fluid move back to the superior oval window as it is pushed to the round window?
There is a membrane in between the two canals (black line) that runs the length of the cochlea called the organ of corti
The organ of corti is composed of:
A. Basilar membrane and Tonotopic membrane
B. Tonotopic membrane and Tectorial Membrane
C. Tonotopic Membrane and Basilar Membrane
D. Basilar Membrane and Tectorial Membrane
Organ of corti made of two things:
Basilar membrane
Tectorial membrane
Differentiate the Auditory system from the pinna to the cochlea into structural categories
External/outer Ear - Pinna - Tympanic membrane
Middle Ear - Malleus -> stapes
Inner Ear - Cochlea and Semicircular canal
True or False. As the perilymph in the cochlea travels, it is able to travel in different directions in order to transduce the vibrational signals into electrical signals.
False, Perilymph travel is very unidirectional. Even as the organ of corti splits the cochlea into 2, The organ of corti prevents the fluid from flowing in all directions. (draw out the figure)
Because the travel of fluid in the cochlea is in one direction, what happens to the fluid once it reaches the tip of the cochlea?
The fluid runs into the round/circular window. The window bulges out but bounces back and causes the fluid to travel in the other direction. This motion of fluid movement continues until the energy of the sound wave has dissipated.
True/False. The Basilar Membrane transduces vibrational information into electrical signals because it is the structure able to capture all frequencies of waves.
False. Though the basilar membrane does contain fibers that move in specific to different cells, the basilar membrane does not have the capacity to transduce these signals. The hair cells fire of the organ of corti move when the basilar membrane fibers move them to translate the signal. This is possible as the organ of corti sits on top of the basilar membrane
Britannica.com
As the fluid in the cochlea flows, not only does it cause certain portions of the basilar membrane to vibrate, what also happens to transduce an electric signal?
A. It pushes up against the round window
B. The fluid flows in the organ of corti as well as on top and under as well.
C. The Endolymph’s travel is separate by the organ of corti
D. Th fluid stimulates the hair cells in the utricle
B. The Perilymph of the cochlea flows all around the cochlea as well to push the hair cells within the membrane to move.
A. this is true, but does not answer the Q
C. Perilymph is in the cochlea. And the separation doesn’t affect transduction but flow
D. The fluid of the auditory system doesn’t connect with the vestibular system
Hair cells of the organ of corti have bundles of hair cells on the most superior portion of the cell called:
A. Stereocilia
B. Cillia
C. Flagella
D. Kinocilium
D. the superior portion of the hair cell called the hair bundles are made of Filaments called Kinocilium (aka microvilli). Each kinocilia are connected to one another by a tip link to increase efficiency and effectiveness of activating the cell.
More often than not, an action potential in a cell occurs when a channel opens to allow ions to flow in. What type of channels are these in the hair cells of the organ of corti? How does the influx of these molecules affect the hair cells?
Potassium gated channels. Opening the channels allow K+ ions to flow in to not only depolarize the cell, but it also causes CA2+ channels in the hair cell to open up as well.
Elaborate on the mechanism to allow gated channels in hair cells in the cochlea to open. What causes this opening?
Tip Links of different kinocilia are stretched as other kinocilia move. This stretching mechanically opens the gated potassium channels.
True/False - A single hair cell has one associated kinocilia to the cell to allow potassium influx to cause calcium channels to open.
False. There are many kinocilium associated with a single hair cell. Therefore a flood of K+ can come from all other kinocilium to induce calcium channels opening at the base of the hair cell.
Ultimately, what two ions in the cochlea are responsible for transducing a sound wave to an electrical wave.
A. K+ and Na+
B. Na+ and Ca2+
C. K+ and Ca2+
D. Na+ and Cl-
C. K+ and Ca2+
What happens when the hair cell fires an action potential?
It sends its signal onto its associated spiral ganglion cell. The spiral ganglion cell sends its signals through the auditory nerve in order to send signals up the brain
The retinal and spiral ganglion cell function in very similar ways. Like the retinal ganglion, does the spiral ganglion cells axons form the main nerve to to ascend into the brain?
No, while the retinal ganglion cell axons bundle as it exits the orbit to form the optic nerve, the Spiral ganglion cells axons synapse onto another cell that is part of the auditory nerve
Along with funneling sound waves into the external acoustic meatus, what other function does the auricle do? To what extent does it work?
It amplifies the sound wave by 2
Understanding that the pressure outside in the environment should be equal to the pressure within the ear canal, how does the different surface area between the auricle and the tympanic membrane affect the different forces on each respective structure?
The pinna is much larger in size compared to the tympanic membrane. Therefore if Pressure is equal to force over an area, and pressure was the same at both structures, then, the force of the pinna is much larger than the force at the tympanic membrane. This signifies a mechanical advantage.
Why is there so much amplification occurring through different structures of the auditory system?
From Physics, as a wave moves changes media, in particular in this scenario from air to fluid, energy is lost due to the resistance that exists at the boundary of this change
Therefore to transmit our signal without losing the signal or energy of the signal, have to amplify this energy because the signal will decrease as it changes from vibrational to fluid (at the cochlea)
Amplification at the Pinna is about 2 times and the ear drum amplification magnitude is….
About 15 times more than the external
Amplification of the sound wave at the ossicles…
A. 2
B. 15
C. 7
D. 3
D. 3. Amplification of the sound wave after the eardrums occurs 3 times more
The most amplification of the sound wave occurs at the ….
The Ear drum. It amplifies the signal by 15 times more
The total amplification of a sound wave you hear at country concert is:
A. 20
B. 19
C. 100
D. 90
D. 90 Auricle/Pinna (2) * Cochlea (15) * Ossicles (3) = 90
Amplification of a sound wave by 90 times from its external environment is equivalent to how many decibels?
This increase by 90 is equivalent to about 20 decibels only
Q - True/False - Endolymph circulates through the cochlea.
False, endolymph can be found in only one area of the body, the semicircular canals. Perilymph is found within the cochlea
Which of the following best describes the difference between endolymph and perilymph?
A. Endolymph is found in the vestibule, while perilymph is found in the cochlea.
B. Endolymph is found in the cochlea, while perilymph is found in the vestibule.
C. Endolymph is found in the membranous labyrinth, while perilymph is found in the bony labyrinth.
D. Endolymph is found in the bony labyrinth, while perilymph is found in the membranous labyrinth.
C. Endolymph is the potassium-rich fluid that bathes the hair cells of the inner ear, all of which are found within the membranous labyrinth. Perilymph is found in the space between the membranous labyrinth and the bony labyrinth. Both the membranous labyrinth and bony labyrinth contribute to the cochlea and the vestibule, eliminating choices (A) and (B)
What is the importance of the round window in the cochlea?
Fluid, unlike gases, are incompressible. Therefore without the window’s flexible characteristic permitting more space, the perilymph won’t be able to travel and sound won’t be processed efficiently or at all.
You are examining your mom’s fetus through an ultrasound and would like to see the correlation of a fetus’s heart rate to the voices both hers and a strangers (you). You recall an NHI article elaborated about fetal increase in heart rates with their mothers, yet see no signs of this on the monitor. What is one dysfunction the fetus might have regarding their cochlear windows that may be present in your child but not in the average fetus?
A dysfunction seen in this fetus regarding the auditory system, maybe due to a rigid cochlear window. A rigid membrane would cause the fluid to not propagate as much and lead a compromised hearing which may be the reason why the fetus doesn’t demonstrate the increase in heart rate after the mom talks.
True or False. The cochlea only contains perilymph while the labyrinth contains endolymph
False. The cochlea is know for containing perilymph, however the scala media contains endolymph while the scala vestibuli and scala tympani contain perilymph
(neuroscientificallychallenged.com)
True or False. Perilymph is also called Scarpa’s Fluid.
False, Endolymph is also called Scarpo’s Fluid after Antonio Scarpa. (wiki)
After the signals are transduced into an electrical signal in the hair cells of the organ of corti, where does the signal travel to? In what pathway?
Travels to the primary auditory cortex through the cochlear n/acoustic n/auditory n.