About this video
Explains sensorineural hearing loss, where the inner-ear conversion of fluid movement into electrical signals fails, and how a cochlear implant bypasses that step. The external microphone and speech processor send sound to an implanted receiver and stimulator that deliver signals into the cochlea and onward along the auditory nerve.
You'll be able to
- describe the normal path of sound from the ear to the brain.
- explain what sensorineural hearing loss is and why an implant can help.
- trace how each part of a cochlear implant passes information along.
Key words
- Sensorineural hearing loss
- Hearing loss caused by a failure in the inner ear or the nerve pathway, often called nerve deafness.
- Cochlea
- The inner-ear structure where fluid movement stimulates hair cells that generate electrical signals.
- Cochlear implant
- A surgically implanted device that bypasses damaged hair cells and stimulates the auditory nerve directly.
- Receiver
- The implanted part that picks up signals from the transmitter and passes them to the stimulator.
- Speech processor
- The external unit that turns the microphone's sound signal into information for the transmitter.
Transcript
In this video, we're gonna talk about cochlear implants. Now, cochlear implants are basically a surgical procedure that attempts to restore some degree of hearing, of the ability to hear, to individuals that have something known as sensorineural hearing loss. And this is otherwise known as nerve deafness.
So let's talk about sensorineural hearing loss real quick. So normally what we have is, we have sound waves coming in, they hit the ear. And then they travel through this auditory canal, cause the eardrum to vibrate back and forth, and this vibration causes these three little bones in the middle ear to vibrate back and forth.
And eventually, fluid moves back and forth in the cochlea, and that fluid movement gets, stimulates hair cells that then produce an electrical signal that gets sent to the brain. Now individuals with sensorineural hearing loss, this conversion over here basically does not work.
So there's a problem with conduction. And this can be surgically treated with something known as a cochlear implant. You know what, let me just write that down, so, "Cochlear implant." So let's talk about a cochlear implant. Let's just look at the different components of the cochlear implant.
So, this implant part, which is what I'm highlighting right here, is known as a receiver. And then from the receiver extends this long kind of tube that goes all the way into the cochlea and turns around like that, and this tube is known as a stimulator. Now, what is the receiver doing?
It's receiving information from this wall structure right here, and this is known as a transmitter. So the transmitter. And the transmitter is getting electrical information from this thing that I'm highlighting now, which is known as a speech processor. Speech processor.
The speech processor basically gets information through this little opening, which is the microphone. So as sound waves come in, they hit the microphone, and the microphone takes the sound waves, converts them into an electrical impulse, which then gets sent to the transmitter, which you can see it some, it's outside of the individual's skull.
And the transmitter sends that information to the receiver, which is inside, it's implanted inside the patient's skull. Then the receiver sends the information through the stimulator, into the cochlea, and then the cochlea converts that electrical impulse into a neural impulse that goes down the auditory nerve into the brain in order for that sound wave to be processed.
And so basically, this effectively restores some degree of hearing to individuals with nerve deafness.
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