Human ear - structure & working | Sound | Physics | Khan Academy

00:07:35
https://www.youtube.com/watch?v=98-6WfdumZY

Résumé

TLDRDeze video legt uit hoe het menselijke gehoor functioneert. Geluidsgolven worden door de oorschelp opgevangen en via de gehoorgang naar het trommelvlies geleid. Het trommelvlies, dat zeer gevoelig is voor trillingen, begint te trillen, wat de drie kleinste botjes in het middenoor, de ossicles, activeert. Deze ossicles versterken de trillingen voordat ze naar het binnenoor gaan, waar de cochlea de trillingen omzet in elektrische signalen. Deze signalen worden via de auditieve zenuwen naar de hersenen gestuurd, waar ze worden geïnterpreteerd als geluid. Het gehele proces, van luchttrillingen tot het ervaren van geluid, is fascinerend.

A retenir

  • 👂 Geluidsgolven worden opgevangen door de oorschelp.
  • 🔊 Het trommelvlies trilt bij geluidstrillingen.
  • 🔗 De ossicles versterken en transporteren geluidstrillingen.
  • 🌊 Trillingen worden moeilijker overgedragen in vloeistof dan in lucht.
  • 🚀 Ossicles verhogen druk van geluidsgolven met 20x.
  • 🐚 De cochlea zet trillingen om in elektrische signalen.
  • 🧠 Hersenen interpreteren de elektrische signalen als geluid.
  • 🔉 Verschillende cellen in de cochlea onderscheiden frequenties.

Chronologie

  • 00:00:00 - 00:07:35

    De video bespreekt hoe geluid wordt waargenomen, beginnend met hoe luidsprekers geluidsgolven creëren door luchtdeeltjes te laten vibreren. Wanneer deze luchtmoleculen in de buurt van onze oren vibreren, ervaren we geluid. De structuur van het oor, bestaande uit het buitenoor, middenoor en binnenoor, wordt uitgelegd. Het buitenoor, met de oorschelp, verzamelt geluidsgolven en geleidt deze naar de gehoorgang en het trommelvlies, dat vibreert als reactie op geluid. Dit leidt tot het middenoor, waar de drie kleinste botten, de gehoorbeentjes (hamer, aambeeld en stijgbeugel), de vibraties doorgeven en de druk van de geluidsgolven verhogen, wat noodzakelijk is omdat het binnenoor vloeistof bevat. De video benadrukt dat de stijgbeugel de druk van het geluid 20 keer verhoogt. Tot slot legt het de rol van het slakkenhuis in het binnenoor uit, waar de vibraties worden omgezet in elektrische signalen die naar de hersenen worden gestuurd voor interpretatie als geluid.

Carte mentale

Vidéo Q&R

  • Wat doet de oorschelp?

    De oorschelp verzamelt geluidsgolven en leidt ze naar de gehoorgang.

  • Hoe trillingen worden versterkt?

    De ossicles in het middenoor versterken de trillingen voordat ze het binnenoor bereiken.

  • Wat doet de cochlea?

    De cochlea zet trillingen om in elektrische signalen die naar de hersenen worden verzonden.

  • Waarom is het moeilijker om te bewegen in water dan in lucht?

    De ossicles vergroten de druk van het geluid ongeveer 20 keer.

  • Wat doet het binnenoor?

    Het binnenoor bevat vloeistof die de geluidstrillingen omzet in elektrische signalen.

  • Waarom heeft ons gehoor verschillende frequenties?

    De cellen in de cochlea zijn gevoelig voor verschillen in frequentie, waardoor we verschillende geluiden kunnen horen.

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Sous-titres
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Défilement automatique:
  • 00:00:00
    [Music]
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    how are you listening to this music
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    right now
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    well you might know that your speakers
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    are creating sound and your ears are
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    listening to it but there's a lot more
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    going on over here
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    you see all your speakers are doing
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    right now is vibrating the particles of
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    the air close to it
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    then they vibrate the air molecules
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    close to them and so on and so forth
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    and we call this a sound wave
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    and eventually when the air molecules
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    close to your ears start vibrating we
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    hear sound
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    but how does something as boring
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    as air molecules going back and forth
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    make us experience something like this
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    [Music]
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    well
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    for that we need to look at our ear
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    carefully
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    i mean the entire structure of the year
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    so let's look at how the different parts
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    of the ear
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    work together to make us experience
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    sound
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    so our ear can be divided into three
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    parts
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    the outer ear
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    the middle ear
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    and the inner ear
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    the outer ear starts with the pinna
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    it's the part that you can see and touch
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    or in my case the part that my mom would
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    twist quite often
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    its job is to collect as much sound
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    waves as possible and channel it into
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    the auditory canal
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    the sound waves pass through the
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    auditory canal and eventually meet the
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    eardrum which is shown in green over
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    here
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    the eardrum is a transparent membrane
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    which is super sensitive to the
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    vibrations of the air so as the air
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    vibrates even the eardrum starts
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    vibrating just like the skin of a drum
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    and as you can see the eardrum also
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    separates
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    the outer ear
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    from the middle ear
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    this brings us to the middle ear
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    the middle ear consists of the three
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    tiniest bones of the human body and
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    they're together called
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    the ossicles
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    and they have pretty cool names they're
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    called the malleus
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    the incus
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    and stapes
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    and here's the actual picture of these
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    three bones
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    and because of their shapes they're also
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    commonly called as the hammer
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    the anvil
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    and the stirrup
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    steer up is where you rest your feet
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    when you're riding your horse
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    all right so as the eardrum vibrates you
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    can see the ossicles also start
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    vibrating transferring the vibrations
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    from the eardrums to the inner ear
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    now their main job is to increase or
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    amplify the pressure of the sound waves
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    when it reaches the inner ear
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    but why do we need to increase the
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    pressure of the sound waves
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    because as we will see the inner ear
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    consists of a liquid
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    not air
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    so the vibrations must transfer into a
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    liquid
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    and you might already know that
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    vibrating or moving particles of liquid
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    is much harder than moving particles of
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    air
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    which is why it's very easy for you to
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    swing your arms in the air but it's
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    pretty difficult to do that inside water
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    like say in a swimming pool
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    and so to set this liquid in vibration
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    the pressure has to be high enough
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    and in fact it turns out that our
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    ossicles increase the pressure of the
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    sound about 20 times
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    but how do they do that
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    well just take a look at the base of the
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    stapes
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    it has such a small area compared to
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    that of the eardrum
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    so when the force gets transmitted from
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    the eardrum to the stay piece it gets
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    concentrated in a very tiny
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    area and you might know when you
  • 00:04:29
    concentrate force in a very tiny area
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    you increase its pressure
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    and that brings us to the inner ear
  • 00:04:40
    the inner ear consists of a bony
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    structure which is shown in purple
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    now as you can see the top part of the
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    structure consists of three semicircular
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    rings
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    they help us in maintaining our balance
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    when walking or dancing or whatever we
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    do so they're not involved in hearing so
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    not so important for us
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    the part that's involved in hearing is
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    this snail-like structure this is called
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    the cochlea
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    what does it do
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    well although these bones have already
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    started dancing to the music nothing
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    gets heard until these vibrations are
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    converted to electricity and sent to our
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    brain
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    and that's exactly what the cochlear
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    does
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    now the cochlea is super complex and
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    it's also a little mysterious
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    even today there are certain things
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    about it we just don't know
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    and so we'll definitely not go into the
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    details but as mentioned earlier it
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    contains a liquid
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    and when the stirrup hits our cochlea
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    this liquid starts vibrating
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    and then there are some specialized
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    cells in the cochlea that convert these
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    vibrations
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    into electrical signals
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    and these electrical signals go through
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    the auditory nerves
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    all the way to your brain
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    where it gets finely interpreted as
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    sound
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    and the cells of your cochlea are
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    amazing
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    the electrical impulses that they
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    generate are super sensitive to how loud
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    the sound is or how feeble the sound is
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    whether it is high frequency or low
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    frequency
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    and as a result your brain can
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    differentiate the tiniest differences in
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    the sound and so you can understand
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    different letters or words or even
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    understand what i'm saying right now
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    or hear the different notes of this
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    music
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    and so to summarize the outer ear
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    collects the sound waves through the
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    pinna and directs them to the eardrums
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    the three optical bones of the middle
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    ear amplify these sound waves
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    transferring it into the cochlea
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    and the cochlea converts the back and
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    forth vibrations of the particles into
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    electrical signals and sends it to our
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    brain
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    and regardless of how many words i use
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    to describe what's going on
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    the very fact that the back and forth
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    movement of the air can be converted
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    into this amazing experience we call
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    sound is truly unfathomable and beyond
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    words
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    [Music]
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    you
Tags
  • geluid
  • gehoor
  • oorschelp
  • vatting
  • cochlea
  • trillingen
  • ossicles
  • geluidsgolven
  • hersenfunctie
  • geluidsinterpretatie