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The eardrums move when the eyes move

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Re: The eardrums move when the eyes move

#41
post #22
post #20

Earlier quoted context omitted.

That's one of the automatic functions of the tensor tympani muscle. It also does it when you talk, and as part of your startle reflex. Fun fact: some people have conscious control of this muscle and can voluntarily "screw up their ears" (at least that's what it feels like, it also makes a roaring/rushing sound) to dampen sounds.

What causes the rushing sound? Blood?

The 30-70Hz vibration of the muscle itself tensing, apparently, according to Wikipedia: https://en.wikipedia.org/wiki/Tensor_tympani_muscle#Voluntar...

Re: The eardrums move when the eyes move

#42

This makes me wonder ... um ... this might be TMI, but I'm wondering if anyone else has experienced a sudden "clearing" of the sense of smell when washing the perineum. Do we have olfactory cells down there that kind of cancel out our own scent? I'll start washing "downstairs" and experience a something analogous to clouds parting, but for smell. It's not the smell of the soap per-se, it's a sudden removal of some ki…

Never heard of it, but I have a weird one too: my left ear pops when I crack my upper back.

Re: The eardrums move when the eyes move

#45

About 5% of the nerves in the auditory nerve are efferent, and act to modulate the firing of the afferent nerves. Perhaps part of the modulation they achieve is to prevent us "hearing" our eyes move.

Ah, for example:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3343276/

"Historical evidence in-vivo suggests that a primary function of the EVS is to tune vestibular sensation to the interest and needs of the organism, for example by decreasing the sensitivity during large self-generated movements [30, 31], and adjusting the background discharge characteristics of afferents [6]."

Re: The eardrums move when the eyes move

#48
post #9

There is a medical condition where people can hear their own eye movements. > The bizarre phenomenon of being able to hear the sound of the eyeballs moving in their sockets (e.g. when reading in a quiet room) "like sandpaper on wood" is one of the more distinctive features of this condition and is almost exclusively associated with SCDS. https://en.m.wikipedia.org/wiki/Superior_canal_dehiscence_sy...

I personally experience this if I forget to take or try to stop taking duloxetine (also known as Cymbalta). It is one of the more annoying and frankly disconcerting withdrawal symptoms. Other fun symptoms consist of "brain zaps" where you suddenly feel like you've been shocked from within your head out of nowhere, anxiety, depression, panic attacks, sweating, and once I was watching TV and the only way I can describe the sensation is that it looked slowed down.

Re: The eardrums move when the eyes move

#50
interestingly the ear has recently been found to oscillate its follicles at frequencies which enhance what the brain wants to hear ... Hudspeth AJ http://dx.doi.org/10.1162/DAED_a_00316 ... science has barely scratched the surface of even the feeblest understanding of biophysics, what a great time to be alive
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