Mechanics of Spinning Around (effects on inner ear)

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The discussion centers on the physiological effects of spinning and the resulting eye movements due to the vestibular system's response. When a person spins, the fluid in the inner ear moves, stimulating hair cells that send signals to the brain, causing involuntary eye movements known as nystagmus. Participants explore the mechanics of fluid dynamics in relation to spinning, questioning how fluid continues to move after stopping. Experiments with spinning water in a glass are suggested to illustrate these principles. The conversation also touches on how the brain processes conflicting sensory information from vision and balance after spinning, leading to sensations of dizziness or vertigo. The importance of understanding the vestibular system and its evolutionary aspects is highlighted, along with practical techniques dancers use to mitigate disorientation.
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Ear biomechanics
Suppose I stood up and spun around in a circle for about twenty seconds and stop.

Then, I ask my friend to look into my eyes (as I try to look into his).

He sees my eyes go back and forth and back and forth (and I cannot stop that).

I vaguely recall someone telling me there is a hair (or fiber) in my ear (somewhere) and when I spin, the turning fluid presses against the hair and sends signal to my brain to move my eyes.

But I do not understand how my spinning can cause the fluid to spin.

Could someone please explain what is happening?
 
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We usually try to answer questions at the level the question seems to be posed. A reasonable answer to this one involves anatomical vocabulary (a lot more than the question uses) - best I can do....
start here:
https://www.verywellhealth.com/vestibular-nerve-anatomy-5092724

Also "I vaguely recall" as a way for us to start answering is not helpful. If you have some kind of reference it usually helps us to give the best possible answer. Am guessing you are asking about recovering from dizziness, therefore I started at the beginning.
So --
Please read the link and come back with questions.

As to a column of fluid spinning try this experiment:

1. half glass of water + floating object - pea size or a wooden toothpick
2. spin the glass dead center on a lazy susan disc -
Lazy susan === those easy-to-rotate flat circular things that usually have lots of junk on them. They live on table tops often. (clear the junk off of it first)
3. what can you see after 10 quick turns and an immediate stop of the spin? Change the number of rotations....
 
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jim mcnamara said:
We usually try to answer questions at the level the question seems to be posed. A reasonable answer to this one involves anatomical vocabulary (a lot more than the question uses) - best I can do....
start here:
https://www.verywellhealth.com/vestibular-nerve-anatomy-5092724

Also "I vaguely recall" as a way for us to start answering is not helpful. If you have some kind of reference it usually helps us to give the best possible answer. Am guessing you are asking about recovering from dizziness, therefore I started at the beginning.
So --
Please read the link and come back with questions.

As to a column of fluid spinning try this experiment:

1. half glass of water + floating object - pea size or a wooden toothpick
2. spin the glass dead center on a lazy susan disc -
Lazy susan === those easy-to-rotate flat circular things that usually have lots of junk on them. They live on table tops often. (clear the junk off of it first)
3. what can you see after 10 quick turns and an immediate stop of the spin? Change the number of rotations....
IGNORE THIS POST: I figured it out.

Thank you!

I understand the document you linked.

However, you have zeroed onto precisely my question:

Yes, I spin the glass of water around its own axis. However, that does NOT apply here.

In my ear, the chamber of fluid is NOT spinning around its own axis. It is spinning around MY axis. So what makes the fluid continue to turn after I stop spinning?

In other words...

Fill a hollow torus with fluid. Put it dead center on the lazy Susan. Yes, the fluid in side will spin. Now put it on the edge (outer perimeter) of the lazy Susan. How does the fluid inside spin?
 
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Trying2Learn said:
Fill a hollow torus with fluid. Put it dead center on the lazy Susan. Yes, the fluid in side will spin. Now put it on the edge (outer perimeter) of the lazy Susan. How does the fluid inside spin?

Try the experiment yourself!
It doesn't even have to be a torus, a glass or shallow bowl of water with perhaps some scraps of paper floating in it so you can see any motion.

Let us know what you see so we can further assist you in your quest for Learning.

Cheers,
Tom
 
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Trying2Learn said:
Yes, I spin the glass of water around its own axis. However, that does NOT apply here.
Hang on. it is spinning around some axis and the lazy Susan experiment is attempting to get down to the basics. If you put the water at the edge of the lazy Susan, you will still get the effect plus the centrifugal force (in the frame of the glass) which will also cause the water to 'lean' slightly because it is orbiting as well as spinning.

Our sensory system has several shortcomings and they tend to be result of evolution and the fact that there are some sensations which we rarely experience - so why expend energy on infrequently used facilities? We are good at detecting changes accurately but we ignore long term sensations. We get used to static upwards forces from the floor (our weight force) but we notice subtle changes as we start to move up and down in a lift, for instance.

In the case of spinning, we have both visual and balance clues. After spinning, the visual clues reset to zero but the balance sensors take some time to reset. So that leads to confusion and nausea etc.. I have experienced Vertigo a couple of times in my life (also been fairly drunk). The sensations from the balance mechanism tells one thing; it makes you think the room should be rotating. The sensation from the vision tells you the room is stationary and you try to chase it with your eyes (irrationally).

We are always dealing with limited angles of rotation so we are good at sensing how much and how fast, up to one rotation, say. Dancers and skaters deal with the problem by 'spotting'. They fix their gaze on a stationary point so that, when they stop, there is less conflict between the two sensory inputs as their head 'thinks' it's been stationary for most of the time (both sensors).
 
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Thanks for the information, all. I did figure it out (and posted at the top), but thanks anyway for the additional information
 

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