# Why can't you hear stuff at the peak of a deep yawn? **URL:** \ **Category:** Factual Questions\ **Created:** [June 3, 2015, 3:15pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538 "2015-06-03T15:15:00Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [June 3, 2015, 3:15pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/1 "2015-06-03T15:15:00Z")
See subject. Just missed my favorite bit of Baby I Love You. ---
**Author:** ![Morgenstern](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@Morgenstern](https://boards.straightdope.com/u/Morgenstern)\ **Post date:** [June 3, 2015, 3:16pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/2 "2015-06-03T15:16:49Z")
> [@Leo\_Bloom](#): > > See subject. Just missed my favorite bit of Baby I Love You. \<3 to you too. Psssst. I can hear stuff. Am I not yawning correctly? ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [June 3, 2015, 4:49pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/3 "2015-06-03T16:49:57Z")
Because of the tensor tympani muscle: > **[Tensor tympani muscle](https://en.wikipedia.org/wiki/Tensor_tympani_muscle)** > > The tensor tympani is a muscle within the middle ear, located in the bony canal above the bony part of the auditory tube, and connects to the malleus bone. Its role is to dampen loud sounds, such as those produced from chewing, shouting, or thunder. Because its reaction time is not fast enough, the muscle cannot protect against hearing damage caused by sudden loud sounds, like explosions or gunshots. > The tensor tympani is a muscle that is present in the middle ear. It arises from the cartilagin... ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [June 3, 2015, 8:55pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/4 "2015-06-03T20:55:29Z")
Whew, asked and answered! Just to bring it on the table, here’s a relevant section of the Wik [text broken for clarity]; I hope I’m not bucking the long-cite rules): **Function** The tensor tympani acts to dampen the noise produced by chewing. When tensed, the muscle pulls the malleus medially, tensing the tympanic membrane and damping vibration in the ear ossicles and thereby reducing the perceived amplitude of sounds.[1] \*\*Voluntary control \*\*Contracting muscles produce vibration and sound.[3] Slow twitch fibers produce 10 to 30 contractions per second (equivalent to 10 to 30 Hz sound frequency). Fast twitch fibers produce 30 to 70 contractions per second (equivalent to 30 to 70 Hz sound frequency).[4] The vibration can be witnessed and felt by highly tensing one’s muscles, as when making a firm fist. The sound can be heard by pressing a highly tensed muscle against the ear, again a firm fist is a good example. The sound is usually described as a rumbling sound. A very small percentage of individuals can voluntarily produce this rumbling sound by contracting the tensor tympani muscle of the middle ear. The rumbling sound can also be heard when the neck or jaw muscles are highly tensed as when yawning deeply. This phenomenon is known since (at least) 1884 (cf : Tillaux Paul Jules, Traité d’Anatomie topographique avec applications à la chirurgie, Paris Asselin et Houzeau publishers (4°ed. 1884, p. 125 )). \*\*Involuntary Control \*\*Tympanic Reflex The tympanic reflex helps prevent damage to the inner ear by muffling the transmission of vibrations from the tympanic membrane to the oval window. The reflex has a response time of 40 miliseconds, not fast enough to protect the ear from sudden loud noises such as an explosion or gunshot. Thus, the reflex most likely developed to protect early humans from loud thunder claps which do not happen in a split second.[5] The reflex works by contracting the muscles of the inner ear, the tensor tympani and the stapedius. This pulls the manubrium of the malleolus inwards and tightens it. This tightening prevents the vibrations from disturbing the perilymph.[6] - off to put a fist in my ear \* ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [June 4, 2015, 2:40am UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/5 "2015-06-04T02:40:54Z")
> [@Machine\_Elf](#): > > Because of the tensor tympani muscle: > > [Tensor tympani muscle - Wikipedia](http://en.wikipedia.org/wiki/Tensor_tympani_muscle) Not neccessarily. It could also be due to the eustachian tube … It is known this is opened during swallowing by contraction of the tensor veli palatini and levator veli palatini, two muscles of the soft palate. It makes sense for the eustachian tube to be opened, so that the tympani cavity doesn’t experience pressure… I just notice that when I yawn I hear the flow of air through my throat area, which is obviously due to the Eustachian tube opening. This means that the hearing of the outside world would also be reduced, because the tympani cavity is not acting as a resonator (as much). Meanwhile I am also deaf to the outside because of the Tensory Tympani as someone else said… too. The function of yawning may be to interrupt hearing, to encourage the person to ignore noise stimulus , and sleep… One can close the eyes to block out visual stimulus … , yawning may well be the closing of the ears… One correlation is not always the one and only causation, the reason yawning developed as a habit or feature, is not necessarily due to the current result of yawning… ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [June 4, 2015, 2:06pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/6 "2015-06-04T14:06:32Z")
> [@Isilder](#): > > Not neccessarily. > It could also be due to the eustachian tube … > It is known this is opened during swallowing by contraction of the tensor veli palatini and levator veli palatini, two muscles of the soft palate. It makes sense for the eustachian tube to be opened, so that the tympani cavity doesn’t experience pressure… > > I just notice that when I yawn I hear the flow of air through my throat area, which is obviously due to the Eustachian tube opening. This means that the hearing of the outside world would also be reduced, because the tympani cavity is not acting as a resonator (as much). Meanwhile I am also deaf to the outside because of the Tensory Tympani as someone else said… too. From time to time my Eustachian tubes remain inexplicably open for a few minutes. I can hear just fine during these times, provided I don’t inhale or exhale too forcefully; that causes pressure fluctuations that stretch my eardrum uncomfortably. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [June 4, 2015, 2:32pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/7 "2015-06-04T14:32:36Z")
I’m pretty sure with me my narrow Eustachian tubes which are constantly clogging up and preventing me from hearing even when I’m not yawning are a big factor. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [June 4, 2015, 2:41pm UTC](https://boards.straightdope.com/t/why-cant-you-hear-stuff-at-the-peak-of-a-deep-yawn/721538/8 "2015-06-04T14:41:07Z")
Way to mix metaphors there, dude. The editor in me wants to change that to “…the _bottom_ of a deep yawn…” or '…the peak of a _high_ yawn…" , or something.