Sound or Silence? The Pros and Cons of Cochlear Implants

Cochlear implants (CI) have been in use for several decades, yet there is still an active controversy surrounding these devices. While some people strongly advocate for the positive effect on an individual’s life, others claim that implants are dangerous both to individual health and to deaf culture at large [1].

PRO
Even though a CI cannot provide 100% hearing capability, it enables the individual to hear and understand most sounds. A cochlear implant does not amplify sounds like common external hearing aids, but stimulates the auditory nerve. The implant essentially replaces the function of the hair cells in the inner ear that usually register sound vibrations.  
Most importantly, a CI enables the individual to hear itself and thus learn to speak and articulate, and thus an implant helps to communicate with hearing people who do not know sign language. It also saves from  lip reading and generally depending on others for hearing help.
Another great advantage of having a CI for young people is that it can help them fully participate in mainstream schools and society, as well as broaden their career choices. While they may still be limited, the limitation won’t be as severe or as disabling as if they had no hearing choices available to them.
Being able to hear is also a measure of safety: the ability to locate sounds allows you to be more aware of perilous situations and hear impending danger such as a car coming from behind.

Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436. - Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=29025007

CONTRA
CI require a surgical insertion and obviously surgery of itself always bears risks. Since the device has become available, risks have been minimized, however, complications may include occasional facial numbness or minor facial paralysis. Among individuals wearing a CI, there is also higher incidence of bacterial meningitis than for the general population. Thus an immunization is recommended. The body may also reject the implant, which could require removal or further surgery.
It is important to keep in mind that a CI doesn’t guarantee that a person will be able to hear and speak at a normal level. In some cases, the person with the implant can only hear some environmental sounds. Particularly for adults who receive the implant, electronic signals might not register fully and some hearing impairment may still occur. Also it is important to acknowledge that the auditory cortex is not used to process sound in the same way if a person has been deaf for a long time, so a CI wouldn't help much. 
Thus parents of hearing disabled children are urged  to make a decision as soon as possible for their child. Most people with an implant still need special help in learning to speak and in many cases they will still be stigmatized. Even though they can hear and speak, their hearing capabilities are not the same as a hearing person's [2]. Luckily, the devices are getting better and improved sound perception lets the wearer of CI integrate better into mainstream society.
Obviously, it takes time to get used to the implant and especially in the beginning, many need to get the CI reprogrammed according to their needs. Also, people with CI are limited on some physical activities, especially those involving contact with water, as this could damage the implant.

Controversy in Deaf Society
The primary controversy regarding CI concerns the definition of deafness as a disability. Recently journalist Enno Park gave a talk at the Berlin re:publica conference , where he spoke about his very personal view on the two (hearing and non-hearing) sides of society [3].
The medical community generally regards deafness as a disability that should be treated, and mainstream (hearing) society is of the opinion that hearing allows for a more fulfilling life. Meanwhile, many individuals who are deaf, as well as others who are familiar with non-hearing society feel that deafness is a cultural identity rather than a disability [4]. As a result, they feel that CI implies that there is something wrong with them that needs to be fixed, and that living as a person with a hearing impairment is inherently less fulfilling than as a "normal" person. Thus, these members of the community perceive putting something technical in their brains as serious affront.
Within the non-hearing community, there is a long history of disagreement: Some signing people feel that CI wearers are betraying their culture. Some even go as far as to describe implantation of children as “child abuse”. Also, with more people wearing CI, the need for sign-language interpreters decreases to the disadvantage of those who still rely on their services. On the other hand, parents that do not want their children implanted have to deal with hostility not only from the hearing community, but also from CI-wearers.




--> Get an idea how sound is perceived, through a CI! <--




Interestingly, the attitude towards sign language differs from country to country. In Germany and France, most people working in deaf education even don't speak sign language, and emphasis is placed on children learning to lip read [2,3]. In contrast, in the US, every police department should have one or more interpreters available on call [5]. It is likely that these attitudes and values will change over time, both with the rise of improving hearing technology and activism from within the deaf community.
The decision to receive a CI is a very personal one that should be considered with the help of a medical professional. Every parent with a hearing disabled child needs to decide for themselves what the best choice for their situation is.

Claudia Willmes
PhD Alumna, AG Eickholt / AG Schmitz

Background:
From 2007 to 2008 I worked at the Institute le Bruckhof in Strasbourg, France -  an institution for hearing disabled children, where many children wore cochlear implants [6]. They received special training in learning language and were encouraged to read lips instead of using sign language. However, I also took classes in an adult education center to learn DGS (German sign language) for one year and attended the university in Strasbourg to learn LSF (French sign language). Thus, I heard opinions from all sides: the hearing, the hearing disabled and signing, and those wearing CI.

[1] www.nad.org
[2] personal communication
[3] talk by Enno Park https://bit.ly/2K3MO8P
[4] Ohio University, The Institute for Applied & Professional Ethics https://bit.ly/2wxdrBg
[5] U.S. Department of Justice  https://www.ada.gov/q%26a_law.htm
[6] www.bruckhof.org/
 

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Retinal Implants

Science fiction movies or novels often pick cybernetic transformations of the human body as a "must-have" for the future. The idea of cybernatically-engineered eyes seems to be very popular.
 
Who would not appreciate a contact lens that connects to the internet and shows you all the information in real time like in the TV series Altered Carbon [1]? Nevertheless, some people have retinal implants or bionic eyes, because they cannot see without them. For example, individuals with neuronal degeneration of the retina have the possibility to get retinal implants to restore some of their vision. There are two diseases that cause the majority of retinal degeneration: retinitis pigmentosa (RP) and age related macular degeneration (ARMD).

Retinal Implants Can Restore Basic Greyscale Vision
RP is caused by mutations in more than 50 different genes, and thus can be inherited. Here, the translation of light to electrical signals by the rod photoreceptor cells is disrupted. The symptoms develop gradually, starting in most cases start with night blindness and loss of the peripheral vision. The symptoms affect both eyes equally. The disease progresses to affect the peripheral visual field and then the central area. Fortunately, only a few patients become completely blind [2].
In contrast to RP, in ARMD the central visual field is affected first. Macular degeneration mostly affects older people and does not lead to complete blindness. Nevertheless, loss of vision in the central visual field greatly affects the quality of life [3].
Fortunately, we live in the 21^st century, so our research on biomedical devices is already quite advanced. Now, patients have the possibility to get retinal implants. These implants mostly work with glasses and a build-in external camera. The camera sends the information to a mini computer. Here the information is processed and send to a retinal implant via cable (see figure). The implant electrically stimulates the nerve fibres similarly to functioning photoreceptors. The current implants are able to restore basic greyscale light perception, so that patients are even able to identify objects [4].

Source: https://bit.ly/2I7HRyk

The Bionic Eye
Argus II, also known as the "Bionic Eye", is the oldest model with an external camera. It has been approved for clinical application in Europe and the US. This device helps patients see patterns of light, which they learn to interpret in time [5].
Similar to the Argus II is the Boston Retinal Implant. The only difference is the amount of electrodes in the retinal implant. The Boston Retinal Implant has a higher resolution due to higher number of electrodes. This model is still being tested in animals and not yet in clinical studies [6].
The Intelligent Medical Implant (IMI) is also comparable to the Argus II. The difference and advantage to the Argus II is that the IMI can be individually calibrated upon implantation. This allows adjustment of visual perception for each patient. The IMI is not available for clinical applications yet, but is in clinical trial in Europe [7].
One disadvantage of all three models are the transscleral cables that connect the outside electronics with the retinal implant. Here, the risk of infections due to long term implantation is higher as for example with a different model, the Epi-Ret 3. This model is also a combination of an external camera and a retinal implant, but there is no external case or transscleral cables. The information is send wirelessly to the retinal implant, where it is translated to electrical stimulation. This is an advantage due to the missing transscleral cables, eliminating problems like infections or other postoperative complications. Epi-ret 3 is currently in clinical trials in Europe [8].

Getting Closer to Natural Vision
A very different model to the ones mentioned so far is the Alpha-IMS. The Alpha-IMS works without external cameras but instead has a retinal implant that consists of a 1500-pixel multiphotodiode array mimicing thereby very closely the natural vision. The light sensitive photodiode responds to light and sends a signal to a subdermal power control. This power control can be charged wirelessly by a handheld device that also adjusts the light sensitivity [9]. The model is currently under clinical trial in Europe and Hong Kong. Unfortunately, there have been cases with corrosion of the implant and subretinal bleeding [10, 11].
In 2014 a review analysed these devices and looked at the visual performance in patients [4]. They showed that the Alpha-IMS and Argus II have the best results, when it comes to visual performance. The best recorded visual acuity to date is 20/1260 of the Argus II [12]. Compared to perfect 20/20 vision, patients remain nearly blind, but they are able to see significantly more than without the implants.
The Alpha-IMS may have a better resolution in a smaller more focused central vision, but the Argus II has a bigger field of view. Similar to the Argus II, the Boston Retinal Implant has an array with more electrodes, and in theory this would give a higher resolution. However, there is still no data to back this up. In addition, these larger devices might create more heat.
In conclusion, there are good options for people with retinal degeneration. Though the presented retinal implants still have limited resolution and biocompatibility, future research will help improving these features. Unfortunately, for the privileged people with intact vision, retinal implants with a wifi connection (still) remain science fiction.

Larissa Kraus
PhD Student, AG Holtkamp


[1] Altered Carbon, Netflix, 2018
[2] https://bit.ly/2r9gZ5C
[3] https://bit.ly/1dBK8yC   
[4] Chuang et al., Br. J. Ophthalmol, 2014

[5] https://bit.ly/1PwBZGY
[6] Rizzo, J. Neuro-Ophthalmology, 2011
[7] Keserü et al., Acta Ophthalmol, 2012
[8] Klauke et al., Investig. Opthalmology Vis, 2011
[9] Kusnyerik et al., Investig. Opthalmology Vis 2012
[10] Stingl et al., Proc. R. Soc. B Biol. Sci., 2013
[11] Zrenner, Sci. Transl. Med., 2013
[12] Humayun  et al., Ophthalmology, 2012

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The Weird and Wonderful World of Body Modifications

Body modification is the deliberate alteration of one's physical appearance. It is the wilful action that produces a permanent or semi-permanent modification to the body that is not normally found in nature. 

In the last 30 years, body modifications have experienced a resurgence and increase in popularity, spanning a wider range of social classes and including a long list of practices. From the simple haircut and earrings to the piercing of lips, nipples and genitals, from eyeball bleaching to subdermal horns or bars, or implantation of bio-polymers to augment the size of breast and buttocks; from anabolic steroid injections for bodybuilding, to extreme fasting- all are examples of altering one's appearance over time [1]. Importantly, many of these practices are no longer related to cultural traditions and have become commercialized and legitimized by society. They are especially influenced by media that dictates the current ideals of beauty and fashion. The perception of beauty and morphing the body to obtain it, however, has evolved over time; and with it have also evolved the techniques and tastes for how to modify the body [2].

A Brief History of Body Modifications

History abounds with examples of body modification. Culturally imposed body alterations have been performed for centuries with strong religious or socio-economical belief. The aristocratic class of Mayan civilisation used to compress the skulls of new born babies. Their cranium would be elongated into a shape believed to resemble that of the gods. In China, the feet of young girls were bound together tightly to reshape them into petit stubs to mimic a lotus flower. These women could hardly walk or work, and as such belonged to the privileged high-classes. Many other cultures, from Japan to the islands of Samoa, have empowered their sense of tribal community by tattooing their bodies and faces with symbols of affiliation. While many of these practices were supposed to enhance beauty or infuse power to the beholder, other alteration included the forceful branding, tattooing or scarification of slaves and war prisoners to symbolise their diminished identity or their status as objectified property [3].

While many of these practices have disappeared, other dehumanising and disfiguring operations, such as female genital mutilation, are still conducted to date. Although all the above examples can be considered forms of body modifications, today the term encompasses a different and largely less harmful set of transformative practices.

A collection of bodymodifications, source: Wikimedia Commons

What Drives Body Modification Today?

The definition of body modification today is based firstly on the concept of voluntarism. It is a practice undertaken by active subjects, often after long consideration of the results and side effects. A second distinction must also be made between voluntary body modification and that due to medical purposes. These include all operations that are required and performed by the medical establishment. Prosthetic fittings, gender reassignment and cosmetic surgery, therefore, while broadly falling under the idea of a physical modification, should not be considered as such [4].

Tattoos and piercings: a style statement

 

Body modification, according to the community that endorses and promotes it today, means piercing, tattooing and cutting - in its extreme forms. Simply piercing one's ears is considered ornamental rather than transformative. Bearers of body modifications sit through hours of excruciatingly painful procedures to obtain what they want. The reasons behind extensive remodelling of the self have been the subject of much investigation - and are, indeed, most fascinating to understand from a psychological point of view. A sense of belonging to subcultural or religious groups or a demonstration of resistance against society are strong motivations driving body alteration. However, the primary force driving the desire to modify some part of the body is embellishment. The transformation is seen as a work of art, a novel quality that renders one more beautiful. Through this piece, the bearer also establishes their identity. They are special and exhibit their distinctive and unique trait to prove it. Reshaping some part of the body may also involve an act of catharsis: either to forget something or to never forget it, and it becomes part of one´s personal narrative of life. The pain felt during the actual operations is another common reason to undergo transformative operations. Testing one's limit, enduring the hardness, feeling the endorphins rush: all generate a sense of pleasure and reward alongside the physical pain, and a potential sense of atonement. Finally, reckless impulsivity also often leads to body modification [5]. But would you not regret waking up with the Chinese symbol for ‘soup’ tattooed on your arm?

Body Modification of the Future?

Body modification today is enjoying a rise in popularity, promoted by tattoo conferences and websites dedicated exclusively to body alteration (for those adventurous, check out BME.com). But what could be the body modifications of the future? Some college students are experimenting with subdermal implants of magnets to perceive the energy fields of metal objects - a sort of sixth sense [6]. But while the power to feel when a mobile phone is charged might be more useful than attractive, will the body modification community accept other forms of aesthetic transformation or enhancement? For example those that could be moulded by genetic modification? It's a brave new world.

by Maria Lucia Pigazzini, PhD Student AG Kirstein

[1] Featherstone, Body and Society, 1999

[2] Adams, Sociologial Prespectives, 2009

[3] Rubin, Marks of civilization, 1988

[4] Lane, Sociology Compass, 2017

[5] Wohlrab et al., Body Image, 2007

[6] Wired Gear http://bit.ly/2soFHnh, 2006