iClicker Module 3 & 4 Flashcards
Which of the following would be almost impossible without your vestibular system?
Driving your car
Playing sports
Reading a book
Dancing
All of the above
All of the above
“no” movement would be an example of…
Yaw
“circular head” movement would be an example of…
Roll
If you are traveling in a car with the cruise control set to 40 mph and your physics friend is sitting in the passenger seat- what would she say about your current acceleration?
There is no acceleration
What is the name of the fluid that is inside the semicircular circular canals?
Endolymph
This structure surrounds the cupula?
Ampulla
The baseline firing rate (no head movement) of a primary afferent is 100 spikes per second. If the current firing rate is 160 spikes per second, which of the following is true?
The head was _ (quickly or slowly) moved so that the hair cells were deflected _ (towards or away from) the Kinocilium
The head was quickly moved so that the hair cells were deflected towards the Kinocilium
The baseline firing rate (no head movement) of a primary afferent is 100 spikes per second. If the current firing rate is 90 spikes per second, which of the following is true?
The head was _ (quickly or slowly) moved so that the hair cells were deflected _ (towards or away from) the Kinocilium
The head was slowly moved so that the hair cells were deflected away from the Kinocilium
On an airplane, why don’t you feel like you are moving forward?
Vestibular system encodes acceleration not velocity
Which otolith would be activated when you start running?
Utricle
(horizontal)
Which otolith would be activated if you reached the end of the bungee cord?
Saccule
(vertical)
If you are spining on a bar stool in the dark… After 1 or 2 seconds you will think you are slowing down. After 30 seconds you will perceive that you are no longer rotating. WHY???
Hair cells respond to acceleration not the constant circular velocity
What would happen if you were abruptly stopped?
You would sense you are going in the opposite direction
True or False: The vestibular information influences other sensory systems?
True
Yes or No: Can you get dizzy in the absence of visual information?
Yes
If you were flying a plane, how do you whether you are accelerating or flying diagonally upward?
The vestibular response is different, so it isn’t a problem
Which symptoms would you associate with damage to the Vestibular system?
Vertigo/ dizziness
Imbalance
Visual disturbances
Nausea
If a tumor was found on the vestibulocochlear nerve- what would be the diagnosis?
Acoustic Neuroma
Which mechanoreceptor would be most important for finding a screw head slightly sticking out of a piece of wood (in the dark)?
Merkel Cell (SA I)
Which mechanoreceptor would be most important for noticing if the football is slipping out of your hands?
Meissner Corpuscule (FA I)
Which mechanoreceptor would be most important for getting ready to catch a ball?
Ruffini Ending (SA II)
Which mechanoreceptor would be most important to determine which type of sandpaper is more find?
Pacinian Corpuscle (FA II)
If the nerves connected to your Kinesthetic receptors was severed, which of the following could you still do in the dark?
Pat your head
Touch your nose
Touch your fingertips
Dance
None of these
None of these
Somatosensory information goes to the thalamus before the cortex. What is a prominent theory for why sensory information goes to the thalamus?
Thalamus plays a role in suppressing the bodies response to sensation during sleep
Which part of the somatosensory pathway is somatotopically organized?
All of them
-Spinal cord
-Medial Leminscus pathway
-Somatosensory cortex
True or False: Somatosensory map equally represents all regions of the body?
False
What is the name of the pathway that carries tactile information to the cortex?
Dorsal column- medial leminiscal pathway
-specially touch
Tactile sensation refers to …
Mechanical stimulation of the skin + pain, itch, and internal sensations
If you were to stick a stimulating electrode into the thumb region of the homunculus, what would happen?
You would feel a sensation in your thumb
What is the name of the receptor critical for perception of the position and movement of limbs in space?
Kinesthetia receptors
The axons of the neural fibers of somatosensory receptors differ in their thickness and the amount of myelin. How do you think that influences you perception?
Bigger => faster (higher conduction and because of the amount of myelin)
Which of the following intoxication syndrome causes your perception of hot and cold to be switched?
Ciguatera- caused by eating contaminated fish
What does it feel like when you get injured?
How might the A-delta and C fibers influence your perception?
Most of the time, you might feel an initial pressure (Big A-delta fibers; fast strong pressure or heat)
Then after slowly pain like a burn (C fibers; slower intense pressure or stimulation: hot, cold, chemical)
Why is it beneficial to sense pain?
List the 3 reasons
-To learn to avoid harmful things
-Protective of already injured body parts
-Localize injuries and take steps to fix it
Why does the body have a mechanism to decrease subjective pain?
In a dangerous situation
(chased by a bear, etc.)
How does the body reduce the feeling of pain?
The descending pain pathway modulates ascending pain pathway
What is the function of the PAG in reducing pain?
The PAG modulates ascending pain information indirectly through several hindbrain regions
Opioid Mechanism of Action: Opioid contribute to pain relief because..
Reduce synaptic transmission of pain signals to cortex
A chemist has modified the chemical structure of an opioid without influencing its potency. He wants
Very Lipophilic
This pathway carries mechanoreceptor information resulting from mechanoreceptor information resulting from Merkel cells
Dorsal column medial lemniscus pathway
-carries touch
A drug that blocks the action of a receptor is called a(n)
Antagonist
What are the 3 semicircular canals?
Superior (Anterior)
Posterior
Horizontal
You are shaking your head “no”. Which semicircular canal are you activating?
Horizontal canal
True or False: Firing rates increase or decrease depending on the amplitude and direction of your head movement.
True
You are a passenger in the car with your friend, Stompy. When the light turns green, he thinks he is starring in the fast and the furious. While your eyes are closed and head is perfectly stationary, you…
Information from your utricle
If you close your eyes and the car is traveling at a constant speed, can you tell how fast you are going?
No, you will not be able to tell
If someone was rotating on a bar stool with their eyes closed, when would they notice movement?
Anytime there is a change in velocity
(speeding up, stopping)
What is the name of the reflex that allows you to fixate your gaze on something while you turn your head
Vestibulo-ocular response
If you just left a cruise ship and was feeling like the earth was swaying underneath you- what would be the diagnosis?
Mal de Débarquement syndrome
(sickness of disembarking)
Which of the following mechanoreceptors are fast adapting?
Meissner corpuscle and Pacinian corpuscle
In the dark, someone places a pencil in your hand. Instinctually, your reposition your fingers so …
Ruffini ending
(finger position)
You are holding someone’s hand. As the person starts to fall, you feel their hands pulling away. Which mechanoreceptor is most responsible for this sensation.
Meissner corpuscle
In the dark, you reach up to feel your friends face. You estimate that they haven’t shaved in two days as it is rougher than unusual. Which mechanoreceptor is most responsible for this sensation?
Pacinian corpuscle
While watching the road, you are able to switch your car’s radio by feeling the bumps on each of the buttons. Which of the mechanoreceptor is most responsible for this sensation?
Merkel cell
What is the name of the mechanoreceptors that transduce pain information?
Nociceptor
How does the descending pain pathway help reduce the level of pain a person experiences?
The descending pain pathway modulates the ascending pain pathway
What is the function of the PAG in reducing pain?
The PAG modulates ascending pain information indirectly through several hindbrain regions
How do opioids reduce your perception of the pain?
Activate the descending pain pathway
