Most of us take for granted the
sounds we hear every single day; whether it’s your loved one’s voice, the birds
chirping or the cars driving by. Just imagine living in complete silence. Unfortunately
this is what over 1,000,000 people, in the United States alone, experience on a
daily basis. Deafness can pose numerous challenges and can often make simple
tasks more difficult.
The
cochlea, the tiny, snail shaped structure in the inner ear is what’s
responsible for the sound that most of us hear. The cochlea has thousands upon
thousands of very tiny nerves, referred to as “hair cells” that are responsible
for picking up different sounds and then sending those to the brain. Damage to
the cochlea and the hairs result in sensorineural hearing loss. Sadly, the
hairs of the inner ear do not have the ability to regenerate themselves.
This is an image of the anatomy of the ear
According
to Micol Busi et. al., deafness/hearing loss can be caused by several things:
disease, congenital/developmental, or acquired causes. Although the main causes
of deafness in adults are exposure to extremely loud noises and head injury,
the main causes of deafness in children are largely unknown. Many expect these
causes to be developmental and/or disease related. Childhood hearing loss can be
genetic, come from ear infections, meningitis, chicken pox, measles, etc. It can
also come from problems in the development of the inner ear. Because the inner
ear, which begins to form only 4 weeks into development, is so incredibly delicate,
one minute mutation can be detrimental.
Fortunately,
there is an incredible piece of equipment that is of tremendous benefit for
individuals with severe to complete hearing loss. Many people will instantly
think of hearing aids but, this device is called a cochlear implant (C.I.). A
cochlear implant is a surgically implanted mechanism that allows for deaf
people to hear! Unlike hearing aids that simply amplify sounds, cochlear
implants replace the function of the damaged hairs. The C.I. sends sound that
travels through the microphone of the device into the implant under the skin where
it reaches electrodes that were placed in the cochlea. These electrodes convert
the sound into electrical impulses that then travel to the hearing nerve,
producing sound for the deaf individual.
This is an image of the external piece and internal piece of a cochlear implant
A
recent study performed by Micol Busi et. al. studied the abnormalities of the
inner ear and genetic mutations that deaf/hard of hearing individuals possess.
They also studied the value of cochlear implants in several patients. The study
was actually quite simple. Micol Busi et. al. took MRIs and HRCTs of several
deaf individuals and several individuals with no hearing loss. The cochlea and
other parts of the inner ear were studied and compared to one another. By
studying neuroimaging, the scientists were able to conclude that genetic abnormalities
account for at least half of profound congenital deafness cases. It was also
concluded that EVA (enlarged vestibular aqueducts), enlargement of narrow bony
canals in the inner ear, is one of the most common malformations that cause
deafness. When it came to C.I.s, Micol Busi et. al. agreed that the devices are
of incredible worth. Besides age, extent of hearing loss, genetics and other
variables that may affect the chance for a patient to receive an implant, the
success rate of those who do receive them is astounding. The future of most individuals with C.I.s are brightened by bettering language and writing skills, communication skills and basic developmental processes.
Having
a brother who has two, bilateral cochlear implants, I cannot express the
value of these devices. They have brought sound into my brother’s silent world.
Cochlear implants can be expensive and require careful handling, as they cannot
get wet. They are also quite limited around the world, especially in third
world countries. Despite these issues, it is my hope that these amazing devices
can be spread to people who do not have access. Although cochlear implants have
provided what seems like miracles to many, scientist will continue their
research and improve upon what they already know. I wonder, instead of
surgically implanting devices, will the technology to repair or regenerate the
damaged hair cells of the cochlea ever be perfected for humans?
Other Resources Used:
I had no idea that such a device existed! You explained how the cochlear implant works very well and gave background information to better understand the research experiment. What are the different degrees of deafness? When would it be necessary to have cochlear implants instead of just hearing aids? I wonder if sound is fully restored after having cochlear implants or just improved. Either way, I'm glad that such technological advances in medicine could help people who are born with hearing issues. This field of research will continue to progress and hopefully scientists will figure out a way to restore the hair cells in the cochlea that is less invasive than surgically implanting this mechanism.
ReplyDeleteKatie,
ReplyDeleteThere are many forms of hearing loss. There are different levels from very moderate hearing loss to complete hearing loss. Cochlear implants are for individuals with severe to complete hearing loss. In my brothers case he has been completely deaf from birth and hearing aids did not help in the slightest. With cochlear implants hearing is not completely restored. Often times very high pitch sounds and very low pitch sounds are not registered. It is also hard to distinguish between and man and a woman's voice with the implant. Hearing with a cochlear implant is very different from what we hear on a daily basis. I can honestly say these devices are incredible. They have allowed for a more normal life for so many people; bettering communication, increasing job opportunities and just increasing the quality of life. It is my hope that this technology continues to grow and allow for completely normal hearing restoration.
It is great to see that your brother has greatly benefited from this device! It just goes to show the potentials that modern medicine has. As you stated, these devices and modern technology are not available in third world countries, but it is it advances like these that could someday make this possible. I have had the opportunity to try out a hearing aide, and it is incredible how just the hearing aides advance sounds! I can't even imagine how the implants enhance sounds even more, bringing clarity with sounds to a silent world for some.
ReplyDeleteAlthough I have heard of cochlear implants before, I did not know very much about them. I never realized that hearing aides would not work for people who were born completely deaf, but it is awesome that there is another option out there for them. I wonder if soon the entire cochlear implant will be internal and underneath the skin. This would help with the problem of having to keep the device dry. With advances in technology, I'm sure this, as well as ways to regenerate or repair the hairs in the cochlea, will be available soon. Also, with advances in other fields such as genetics, it will be interesting to see if they come up with other types of treatment or prevention for congenital deafness. It is wonderful to see all these new discoveries and how they are helping all types of people all over the world.
ReplyDeleteHaving a sister with a cochlear implant, I can resonate with the importance of these devices in the daily lives of individuals. The amplification that these devices can have on people with varying levels of hearing loss is truly amazing. The cost of these gadgets can be pretty expensive especially with some insurances not covering the majority of the costs. With more research and further development of these instruments, the cost of these device can go down and we can potentially benefit third world countries with lower economic means. I wonder if new treatments will soon be developed in terms of regenerative restoration of hearing loss by other means, aside from cochlear implants in order to benefit those who cannot afford these expensive devices. These studies are crucial in the 21st century in order to provide the best care for individuals experiencing these hearing deficits.
ReplyDeleteI think you did a wonderful job at effectively explaining not only the cochlear implant but also the causes and effects of hearing loss. It is absolutely incredible to sit back and think about all the minuscule things that can go wrong along the way in development that can lead to such a substantial outcome like an individual's complete inability to hear. I also think the limitations to the device are interesting, for example you stated the severity of the patient's hearing loss as one of the determining factors for whether a cochlear implant is the correct treatment or not. Greg made a good point above suggesting that the internal implantation of the device could solve the problems of careful handling and avoidance of water. Regardless of these specifics, I think that the cochlear implant is another example of science and technology coming together to better the health and lives of many.
ReplyDeleteThe cochlear implant is a wonderful device to allow people who are deaf and are hard of hearing to have the capability to hear. The article I wrote about actually did a study on the regeneration of hair cells so that there is no surgeries that are needed. They used stem cells in efforts to differentiate these stem cells into hair cells. However, more research still needs to be done since only 50% of the experimental mice had restored hearing. As stem cell therapy becomes more researched and its mechanisms are more understood, there is a high probability in the future that there will be an ability to regenerate hair cells and other cells so that surgeries are not needed.
ReplyDeleteIt is amazing to see so many advancements being made in this area! Between cochlear implants and stem cell regeneration of hair cells, the future is looking bright for those who are deaf. If stem cell regeneration proves to be effective in humans, I wonder which route doctors will take/which will wind up being more successful. Either way, I think that these improvements are just the start. I'm sure that scientists will eventually find a way to eliminate the water sensitive aspect of cochlear implants. I wonder if these implants help with balance as well.
ReplyDeleteHello Hannah,
ReplyDeleteI think you did an awesome job summarizing this article and the topic is very interesting. I think that it is unfortunate that hearing loss is so dominant in this country alone and that the causes of hearing loss is largely unknown, especially in children. I never knew that there were other devices to help with hearing loss besides hearing aids, so learning about the cochlear implant was pretty interesting. I wonder if the cells that become damaged in the cochlea can be regenerated somehow using stem cells?
This method of hearing treatment is interesting, as it is something I have never heard of for how effective it can be. Similar to Grace’s post, there are always improvements to be made on existing methods, but the initial success is promising for those suffering with hearing loss. Between both treatments in the articles, it seems that eventually all will be able to hear regardless of the health of their ears, with little inconvenience to the patient. Seeing as a million people already suffer, this number will only grow, emphasizing the importance of research in this field.
ReplyDeleteI am so glad that you included an explanation on how these implants work because although I have known about them for awhile, it has always just seemed like magic than an actual scientific device. I have had the honor of meeting some amazing people that are truly examples of how the C.I. is an advancement that can greatly increase the quality of life for someone who is deaf. My boyfriend's brother has been deaf since he was a toddler due to meningitis. He has had a C.I. since he was in his upper teens and has since graduated from Le Moyne and become a doctor! Although I do not know any sign language, I am able to hold full conversations with him. Additionally, I used to babysit a young child when I was in high school who also had a C.I. Once again, I was able to communicate normally with him and he was able to attend public school. This just shows how this device is a great advancement for any age, young children and adults alike. I cannot speak highly enough of cochlear implants and I really do hope that research continues in the future to just keep furthering its advancements!
ReplyDeleteIf most of the deformities causing the deafness are caused by genetics I wonder if the CRISPR technology could help correct the deformations. In the mean time before technology gets to the point where it can fix health problems like this I think these are a great thing to allow people to hear. I think that they should definitely work on making them waterproof because all of the kids that I know love to go swimming and its not fair that these kids can't go swimming with their friends because of the implants.
ReplyDelete