Hairs that hear?
These chatty cells are responsible for sending signals to the brain for the actual process of hearing.
What are Inner Hair Cells?
Expanded answer: Outer hair cells are responsible for cochlear amplification through its electromotile response.
This location on the basilar membrane is thick and narrow (stiff), making it the location that responds to higher frequencies.
What is its base?
Expanded answer: The basilar membrane is thick and narrow at its base and wide and thin at its apex. This makes higher frequencies more responsive at the base and lower frequencies more responsive at the apex.
This nerve is responsible for transmitting auditory and vestibular information to the brain.
What is CN VIII?
These emissions show that we are active participants in hearing.
What are otoacoustic emissions?
Expanded answer: It was thought that we were passive participants in hearing, but our inner ears produces sounds that are caused by the movement of OHCs.
The auditory pathology that causes Carhart's notch.
What is otosclerosis?
Expanded answer: Otosclerosis causes abnormal bone growth in the middle ear. This tends to fix the stapes in place, preventing it from vibrating properly and transmitting sounds to the inner ear.
Carhart's notch is a distinctive feature in the audiogram that shows a dip in bone conduction thresholds around 2000 Hz.
These "dancing queens" boost the response of the basilar membrane due to their unique response to stimulus.
Who are the Outer Hair Cells?
Expanded answer: The outer hair cells physically change shape in response to stimulus at their characteristic frequency which moves the fluid in the cochlea. A protein called prestin is attributed to OHC motility.
This misnomer is the term that is used to describe the way vibrations travel across the basilar membrane.
What is a travelling wave?
Expanded answer: With a string, if you cause a bit of vibration at one end you will see it vibrate to the other end in the same way the entire time. This is not how the basilar membrane works.
This part of a neuron is responsible for receiving signals from other cells.
What are dendrites?
The downside to using this mode of hearing sound in a clinical setting is that it is hard to isolate one ear, which means there will be no ear specific information.
What is bone conduction?
The two types of professionals you would refer a patient to for suspected pathology of the outer or
middle ear.
What is an audiologist and an otolaryngologist (ENT)?
Expanded answer: An audiologist would be needed to evaluate the degree of impairment and an ENT to offer rehabilitation in the form of surgery or other types of rehabilitation that an audiologist cannot perform.
This process causes hair cells to respond quickly to sounds.
What is depolarization?
Expanded answer: Depolarization is a change in electrical potential existing between the inside and outside environments. In the cochlea, this happens as the negatively charged hair cells are flooded with positively charged endolymph.
This theory says that the more spikes a sound induces, the higher the intensity of the sound.
What is temporal theory?
Expanded answer: Place theory says that louder sounds respond to different places in the cochlea.
This type of frequency information is at the core of CN VIII.
What is the lowest frequencies?
Expanded answer: CN VIII is is tonotopically organized, meaning the lowest frequency information is at the core and as we move out from the core, the frequencies get higher and higher.
The advantage of using this kind of otoacoustic emission testing is that it is quick and is a passive form of testing.
What is Transient Evoked OAEs?
Expanded answer: The downside is that we cannot get any specific frequencies tested, but it does give us good information on the health of the OHCs in the cochlea.
Damage to this part of the cochlea would result in difficulty in hearing in places with background noises, also known as auditory processing difficulties.
What is Inner Hair Cells?
Loss of these cells can result in a loss of frequency selectivity and sensitivity.
What are Outer Hair Cells?
This theory says if you have damage to the basilar membrane at the area that best responds to 2000 Hz, you would have hearing loss at 2000 Hz.
What is place theory?
Expanded: Place theory says when a neuron in a specific place is activated, the brain would identify that as a specific frequency.
This cranial nerve can make it feel like you need to cough when you stick a q-tip in your ear?
Evoked OAEs cannot give us information on this part of the hearing process.
A flat hearing loss pattern is seen in patients with age related hearing loss due to a breakdown in this essential inner ear function.
What is endocochlear potential?
Expanded answer: This is known as metabolic hearing loss. This kind of hearing loss can be easier to fix as there is no mechanical failure of the anatomy of the ear, rather the volume just needs to be turned up a bit (can be bypassed with hearing aids).
Uh-oh, this neurotransmitter released in response to loud sounds is toxic to the hair cells in our cochlea.
What is glutamate?
Expanded answer: this can cause the synapses in the hair cells to die
The issue with this theory is that it ignores tonotopic organization and one neuron cannot keep up with the firing rate of high frequency sounds.
What is temporal or phase locking theory?
Expanded answer: Temporal theory says that cells will fire at the same pattern as incoming sound, so a 1000 Hz sound would vibrate 1000 times per second and the neuron would fire 1000 times in a second to communicate that frequency to the brain.
These type of neurons originate within the body and take information up to the brain.
What is afferent neurons?
This equation can find the primary distortion product frequency.
What is 2f1-f2?
You should use this term when referring to children who have never had the ability to hear before rather than using the term hearing loss.
What is hearing impaired?
Expanded answer: Because there was no hearing to begin with, hearing loss is not a good way to refer to these children's situations.