Auditory + Vestibular system - Basta Flashcards
What are 3 evolutionary advantages of hearing?
- early detection of enemies
- detection of prey
- complex communication bw group members
What is detected by the auditory sense if we hear a sound?
-fast local pressure changes
What does the frequency of a sound represent?
pitch (due to wavelength)
What does the amplitude/intensity of a sound represent?
loudness
What is a ‘beat’?
- an overlay between 2 frequencies
- have areas where 2 waves are in phase, constructive interference –> hear sound
- have areas where 2 waves are not in phase, destructive interference –> do not hear a sound
What hearing organs are unique to insects?
- Johnston organ –> detects pressure changes in the enviro
- Tympanal organ –> part of the development of the true tympanic membrane
Which of the following are true?
Hearing in amphibians…
A. involves the Johnston organ
B. involves a hearing organ and a vestibular organ
C. involves a hearing organ only
D. involves a cochlea
E. involves a perilymphatic space high in Na+, and an Endolymphatic space high in K+
B. involves a hearing organ and a vestibular organ
D. involves a cochlea
E. involves a perilymphatic space high in Na+, and an Endolymphatic space high in K+
Birds have a scala media, a scala vestibuli, and an oval window.
A. true
B. false
A. true
Mammals have…
A. an external ear canal B. a middle ear C. a Tympanic membrane D. a cochlea and a vestibular organ E. all of the above
E. all of the above
What is the hearing range for speech (in dB) and why is it important?
0-20dB
-important because this range is the area of best hearing
What are the bones of the middle ear and which one is the second space of amplification?
- malleus
- incus
- stapes –> the second space of amplification. Is connected to the oval window - cochlea
What are the components of the organ of corti?
- Scala tympani
- Scala vestibuli
- Scala media
- Stria vascularis
The outer hair cell is involved in activating APs while the inner hair cell is involved in amplification.
A. true
B. false
B. false
The outer hair cell is actually involved in amplification while the inner hair cell is involved in activating APs .
Select the true statements.
In outer hair cells…
A. a contracted cell –> depolarization
B. a contracted cell –> hyperpolarization
C. an elongated cell –> depolarization
D. an elongated cell –> hyperpolarization
E. the function is to amplify mechanical signals
A. a contracted cell –> depolarization
D. an elongated cell –> hyperpolarization
E. the function is to amplify mechanical signals
In damage due to hearing loss, the outer hair cells are the first to be damaged, and the sound must be much louder to get the same sensation as in a normal hearing patient. What shift in dB does this damage cause?
a shift of around 40 dB
In diagnostics…
A. if you’re using bone conduction, the sound is transmitted via the middle ear
B. if you’re using air conduction, the sound is transmitted via the middle ear
C. if you’re using bone conduction, the sound is not transmitted via the middle ear, only via bones –> cochlea
D. if you’re using air conduction, the sound is not transmitted via the middle ear, only via bones –> cochlea
B. if you’re using air conduction, the sound is transmitted via the middle ear
C. if you’re using bone conduction, the sound is not transmitted via the middle ear, only via bones –> cochlea
What is correct about mechanical-electrical transduction in inner hair cells?
A. mvmt to the right = depolarization B. mvmt to the left = hyperpolarization C. depolarization decreases frequency D. hyperpolarization is inhibitory E. all of the above
A. mvmt to the right = depolarization
B. mvmt to the left = hyperpolarization
D. hyperpolarization is inhibitory
What is an electro-cochlear-gram useful for and what does it measure?
- can be used to check different phases of the auditory system (depolarization vs. AP)
- cochlear microphonics (CM)
- -> when hair cells are depolarized, can check if depolarization is happening properly
- can check neurons, see if they respond to the sound