9
$\begingroup$

When I yawn I can't hear anything happening around me. I also feel some kind of muscles inside my head contract and hear a faint hum, but it is not loud enough to explain not hearing other sounds. I can force those muscles to contract even without yawning and it produces the same effect of humming and no other sound, so I suppose they cause this effect, but how?

What really happens? What muscles do I feel?

$\endgroup$
  • $\begingroup$ There may be some clues here. it sounds as if you may have some voluntary control over the opening of your Eustachian tubes as described in the article. $\endgroup$ – Alan Boyd Jan 20 '13 at 14:09
7
$\begingroup$

It is related to Eustachian tube. It links the back of throat and the middle ear and allows air pressure to equalize in the middle ear. When you yawn air pressure goes up in this and it bends the ear drum and causes impair hearing (notice, just impair and not stop). Yawning also helps to open Eustachian tube.

$\endgroup$
  • 1
    $\begingroup$ This answer contradicts itself. You are correct in saying that yawning opens the Eustachian tube, and it does this precisely to keep the pressures equalised - so why would yawning 'bend' the ear drum when the tube is open? (This is the same effect that you experience in an aeroplane during landing - anything that you can do to open the tube, including yawning, will restore impaired hearing caused by pressure changes. $\endgroup$ – Alan Boyd Jan 21 '13 at 14:04
  • $\begingroup$ Function of Eustachian tube is equalization of pressure. But yawning create pressure in Eustachian tube and cause bend. $\endgroup$ – MySky Jan 21 '13 at 20:53
0
$\begingroup$

Yawning increases pressure in eustachian tube because it takes place during inspiratory phase of respiration, so pushes Ear drum on the outer side

$\endgroup$
  • 3
    $\begingroup$ Welcome to Biology SE! I think this is a great answer, but could you elaborate a bit more? For example, why would a (more or less) static pressure difference affect frequency analysis in the kilo-Hertz domain? Also, a reference would be nice, or a picture, a website... $\endgroup$ – AliceD Mar 25 '15 at 12:27
  • 1
    $\begingroup$ Plus, it may not add anything to the existing answers in its current form. Please elaborate. $\endgroup$ – AliceD Mar 25 '15 at 12:28

Not the answer you're looking for? Browse other questions tagged or ask your own question.