It’s Not Just RoboCop, It’s Your Grandmother With a Pacemaker

Cyborgs are hybrid creatures, unsettling by nature. They have been used in the arts as symbols of both the progress and dangers brought by scientific discoveries. They are objects of both fascination and disgust. They are, therefore, often a great testimony to the preoccupations of the period and give us an idea of how our ancestors imagined the future of humanity, our present.

The word „cyborg“ is the contraction of cybernetic organism. For the purposes of this article, we will define it as an organic being with mechanic body parts. It applies to an organism that has restored function or enhanced abilities due to the integration of some artificial component or technology that relies on some sort of feedback.The term was created in 1960 by Manfred E.Clynes and Nathan S.Kline to refer to the enhanced man who could survive in extra-terrestrial environments [1]. But more on space exploration later…
First, we have to go back to the earliest occurrences of cyborgs in arts which date back from the mid-XIX century.

The steam concert by Grandville, Jean-Jacques, 1844 

Rust, Bone and Steam - the Early Cyborgs
The first visual appearance of cyborgs dates from 1844. Le concert à vapeur (The Steam concert) presents a band of musicians that have integrated their instruments into their bodies, and have steam coming from their heads. It’s a strange, humorous and an enticing idea if you ever had to carry around a heavy cello or a tuba [2].
The master of the fantastic, Edgar Allan Poe, also tackled the concept of cyborg in a beautifully written short story The Man That Was Used Up (1839). Obsessed by the physical perfection of the mysterious Brevet Brigadier General John A. B. C. Smith (including his moustache [3]), the protagonist runs around the city to learn his story, only to discover that the handsome officer is more a puzzle than a man. At the time of the colonial wars and the industrial revolution, Poe plays with the imagery of the strong warrior and questions the increasingly important place of mechanisation in everyday life.

A Pacifist Dystopia
In the aftermath of World War II, artists tried to think of solutions to ensure a lasting peace. In Limbo (published in 1952 but set in 1990), Bernard Wolfe imagines a world where humans try to suppress their aggressive impulses by performing voluntary amputations of their arms and legs. Unfortunately, the science of prosthetics progresses too, and the new limbs end up being better for war than the natural ones. The description of this society of limbless men extends to social, sexual and philosophical problems as well. This satire is also a severe critic of totalitarian thinking and acting [4].
In his 1963 novel The Three Stigmata of Palmer Eldritch, Philip K.Dick imagines a bleak future for humanity. In the year 2010, the earth has become so warm that one must carry an individual cooling system to venture outside during the day. Mars and a few other planets are inhabited by human colonists forced into exile by a draft. Their only escape from their life on a desolated planet is to chew a hallucinogenic drug: Can-D that “translates” them into a parody of the earth. Then Palmer Eldritch, an enigmatic cyborg space explorer believed to be dead comes back from a system far away. He brings with him an incredible new drug, whose potential to create hallucinated worlds goes far beyond what could be experienced with Can-D. However the nature of the drug and his motive soon appear to be very sinister. In this rich novel, the character of Palmer Eldritch is presented as a futuristic incarnation of the devil, coming to tempt and judge humans.
“The elevator arrived. The doors slid aside. Inside the elevator waited four men and two women, silently. All of them were Palmer Eldritch. Men and woman alike: artificial arm, stainless teeth… the gaunt, hollowed-out grey face with Jensen eyes.” [5]. 

https://bit.ly/2IFpT3c via pixabay

Welcome to the Era of the Macho-Cyborg
Of course, there are multiple examples of cyborgs in Sci-Fi television series such as Star Trek, Doctor Who as well as in the Marvel universe. Too many in fact, to present here. However, I feel I should mention the The Six Million Dollar Man which aired between 1973 and 1978 as it remains a reference in popular culture. Steve Austin, former astronaut with bionic arms is a friendly cyborg, who looks completely human most of the time and works for the US government. Contrarily to earlier examples of cyborgs, there is nothing scary about him.
Austin was soon followed by another righteous cyborg: Robocop. In Paul Verhoeven’s movie of the same title, (1987), RoboCop is a police officer killed by a gang of criminals and later revived as a powerful cyborg who violently fights crime and corruption. However my favorite “cyborg civil servant” character has to be Inspector Gadget. I grew up watching the excellent animated series (which originally aired between 1982 and 1986), which has the best theme song ever. I dare you not to immediately google it. Of course, there is also a 1999 movie directed by David Kellogg.
These three different characters are examples of the late 70’s-80’s concept of a cyborg as an improved man, ultra-masculine without the satire of earlier depictions (from E.A. Poe or B. Wolfe). Moreover, the cyborg is not seen as a threat anymore, but as the next step in the human evolution, helping to solve the problems of our society.

Entering the Cyberspace
Then, there are the cyborgs whose bodies are entirely artificial. Let’s talk about Ghost in the Shell. Before the recent Hollywood adaptation, Ghost in the Shell was a manga from Masamune Shirow published in 1989 [6]. The protagonist Motoko Kusanagi is a woman whose mind (her “ghost”) now lives inside and artificial body (the “shell”). Here, the body and the mind are presented as two different entities. Indeed Motoko is able to leave her body and enter the cyberspace to hack computer systems or find other “ghosts”.
Motoko: “Just as there are many parts needed to make a human a human, there’s a remarkable number of things needed to make an individual what they are. A face to distinguish yourself from others. A voice you aren’t aware of yourself. The hand you see when you awaken. The memories of childhood, the feelings for the future. That’s not all. There’s the expanse of the data net my cyber-brain can access. All of that goes into making me what l am. Giving rise to a consciousness that l call “me”.”
This duality has been perhaps best introduced by William Gibson in his iconic novel Neuromancer. In this 1984 (so pre-internet) thriller, Gibson develops the concept of cyberspace (a term he invented). In this world, most people are cyborgs. However, implants are not enough to render life bearable, and when the protagonist is not able to enter cyberspace, because his nervous system is damaged, he feels trapped.
“For case, who’d lived for the bodiless exultation of cyberspace, it was the Fall. […] Case fell into the prison of his own flesh.”[7]
I cannot conclude this article without a few honorable mentions to pop culture characters who are cyborgs, even though you might not see them that way: Darth Vader, Edward Scissorhands but NOT the Terminator (despite what he says repeatedly during the movie, he is a robot – not a cyborg).

https://bit.ly/2DLDrH6 via pexels

When Reality meets Science Fiction
To misquote Gray, Mentor & Figueroa-Sarriera, science-fiction writers and the editors of the Cyborg Handbook [8]: "It’s not just Robocop, it is (y)our grandmother with a pacemaker“.
Today, cyborgs are living among us. A British man -Niel Harbisson- is the first official human cyborg. Born colour-blind, Niel Harbisson had an antenna implanted into his occipital bone in 2004. It allows him to hear colours including infrared and ultraviolet. The antenna detects the wavelenghts of the colour in front of him and produces a sound that he hears through bone-conduction [9]. Since the antenna now appears on his passport, he has been recognized in 2018 has the first human cyborg by the Guinness Book of World Records.
Although the term cyborg now officially also refers to a real being, reality has yet to catch up with fiction. Artists have been dreaming up cyborgs for over 170 years. In addition to being highly entertaining, science fiction novels and movies inform and alert us to the shifting of our society by imagining worlds with different possibilities for the evolution of humanity.

Aliénor Ragot
PhD Student, AG Holtkamp

[1] Clynes and Kline, Astronautics 1960.
[2] Grandville and Taxile Delord, Un Autre monde : transformations, visions, incarnations, ascensions.1844
[3] "You perceive I cannot speak of these latter without enthusiasm; it is not too much to say that they were the handsomest pair of whiskers under the sun", The Man That Was Used Up p.361

[4]  Anonymous, Psychiatr Q, 1953
[5]  The Three Stigmata of Palmer Eldritch p. 171
[6] Shirow, Ghost in the Shell, 1989 (manga); Oshii 1995,2004,2008 (animated films); Sanders 2017 (live-action film)
[7] Gibson, Neuromancer, 1984
[8] Gray, Mentor & Figueroa-Sarriera, The Cyborg Handbook, 1995 p. 2
[9] https://bit.ly/2L5nyjA

“How Did That Get There?” - Foreign Objects in the Brain

The brain is our inner sanctum, containing every experience of consciousness, sensation, and memory. It’s cradled in the skull, meninges and dura mater, as well as aggressively defended by a special wing of the immune system. There is no way that anything should get in (or out). However, because of this very organ, humans are ingenious creatures and always can find ways to do incredibly stupid things. This article is not for the faint of heart.

“But I saw it on the internet….”
As I was researching this article, I quickly learned (to slight disappointment) that many stories entitled ‘Man or Woman had XYZ in Brain’ had pretty dodgy concepts of anatomy. We will start with the obvious: the brain is encased in the skull, and has no immediate access to the outside world. Some routes may be shorter than others, like the thin sheet of bone above the nasal cavity, but without blunt trauma they’re tightly sealed.
For example (apologies in advance to all arachnophobes), spiders can very easily wander into or lay eggs in your ears. However, to make it to the brain, they would have to make a hole in the eardrum, wander all the way through the cochlea and somehow squeeze their way along the auditory nerve. So the stories that you may hear about referring to ant colonies growing in an individual’s brain? Undoubtedly fake.

Misplaced Objects
As one might suspect, a lot of foreign objects find their way into the brain via tragic or unfortunate circumstances. For example, two Turkish neurologists reported a seemingly normal man who was discovered late in life to have three needles in his brain. His only symptom? A few headaches. The authors suspected that the needles were from a failed homicide attempt when the man was an infant. He survived the removal surgery, and presumably went on with his life [1].
As with other types of surgeries, it is also possible for tools, gauze, or other implements to be left behind in the brain. Tissue grows around these foreign bodies, and infection or abscesses may occur if not caught in time (usually by neurological symptoms). Most (but not all!) of the time these remnants can be removed, and one may assume that a malpractice lawsuit soon follows.
One of the more famous examples of foreign objects in the brain came from a man named Dante Autullo in 2012 [2]. He was using a nail gun to fix a shed, and somehow misfired it into his own head. His friend cleaned up what looked like a surface wound, and they continued building. The next day Autullo was feeling slightly nauseous, and a trip to the doctor ended with him getting a nail removed from his brain. He survived without further impairment. Compare this with the very famous case of railroad worker Phineas Gage, who took an iron rod to the head. He, too, survived without neurological symptoms, but his peers noticed a massive change in personality until he died twelve years after the accident [4].

Radiology Picture of the Day, Courtesy Dr. Laughlin Dawes. Pictured is a CT scan of a patient who pushed a ballpoint pen through the eye socket (and survived).

Squirm-Inducing
Apart from trauma, there is a more insidious and infinitely more gross way that things can get into your brain: parasites. For example, the pork tapeworm Taenia solium can enter the bloodstream from poorly-cooked food, and invade the skin, eyes, and brain. The danger here is not acute, but rather builds up over time as the body forms cysts trying to isolate the parasite from brain tissue [3]. Depending on where these cysts develop, this can cause seizures or other neurological complications. In developing countries, it is estimated that up to a relatively high percentage of the general population is a carrier of the tapeworm, but the fraction of those burden with neurological problems is unknown. Treatment of these brain invaders is also complicated, as the most common antiparasitic drugs cause severe tissue inflammation, which in the brain can be fatal. Often, surgical excision of the cysts is the only option [5].

The brain lesion was... moving.

But for the maximum gross-out factor, let’s also spend a moment talking about larger critters. In 2010, a British man visited the doctor complaining of headaches, strange smells, pain and other vague symptoms. He was tested for just about every neurological disease under the sun, including dozens of brain scans, but doctors couldn’t figure out what was wrong. It was only when a neurologist compared the scans over time that they noticed that a small brain lesion was… moving. Yes. He had a living worm in his brain. It turned out to be a rare type of frog parasite, and was genotyped in the hope of better diagnosing infected patients in the future [6]. Cases like his are (thankfully!) extremely rare, but do still pop up from time to time...

No Entry
In short, having anything in your brain besides neurons, glia and supportive cells is bad news. It takes a keen eye and a good neurologist to spot and deal with the problem, and all of us are better off avoiding these situations all together. So, keep pointy objects away from your head and cook your food well.
Oh, and don’t believe everything that you read online.

Constance Holman
PhD Student, AG Schmitz

[1] Pelin and Kaner, Neurol Int 2012
[2] https://bit.ly/2jNy3vL
[3] https://bit.ly/2rxLsvq
[4] https://bit.ly/2L4vhPc
[5] White, J Infect Dis 2009
[6] Bennett et al., Genome Biol 2014



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Something Fishy Going On - The Impact of Nanoplastics on the Behaviour of Fish

With the enormous rise in plastic use and production within the last century, we are now coming to terms with the impact plastics are having on our environment.

As a result, an expanding area of research that is the study of how microscopic plastic particles less than 100nm in size, referred to as “nanoplastics” (NPs), could potentially be the most hazardous form of marine litter [1]. Due to their small size and therefore high surface area, toxic chemicals can be retained by NPs and could lead to an accumulation of these toxins in marine organisms once the NP pass through membranes and into cells [2].

Krill, Source: Wikimedia Commons

With the ability of NPs to cross from the blood and into the brain, plastic deposits were found in the brains of the tiny crustaceans Daphnia magna, which were kept in water enriched with nano- and micro- sized particles [3]. The direct effect of these NPs can be seen in the behaviour of Daphnia: those who consumed the plastics showed a dose-dependent higher incidence of death; at lower, less fatal concentrations, NPs slowed the eating and preying behaviours [4].
Another question that researchers are investigating is whether NPs can be passed up the food chain as smaller creatures like Daphnia are eaten in large numbers by bigger fish. It has been found that NPs administered to algae become accumulated in fish and have a profound effect on their eating and shoaling behaviour, as well as changes in their metabolism [5].

Can plastic nanoparticles alter behaviour?

It is important to note that the occurrence of NPs in the natural marine environment has not yet been proven, and the above mentioned studies used much higher concentrations that would be found in nature [1]. However, these results can be seen as a wakeup call to start thinking of the impact our plastic use has on the environment.

Joanne Falck
PhD Student, AG Garner

[1] Koelmans et al., Marine anthropogenic litter, 2015
[2] Velzeboer et al., Environ. Sci. Technol. 2014
[2] Mattsson et al., Scientific Reports, 2017
[3] Mattsson et al., Environ. Sci. Technol, 2015
[4] Mattsson et al., Environ. Sci. Technol, 2014

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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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Futuristic Brain Implants: Review of the Series "Black Mirror"

Black Mirror is a  British Sci-Fi series created by Charlie Booker which explores diverse day-to-day topics from our obsession with social media (Nosedive, Series 3 Episode 1) to things which we can't even imagine, like placing a person's consciousness in a physical object (Black Museum, Series 4  Episode 6)! They often delve into neuroscience in the not-so-distant future, in particular, the ways in which different sorts of technology change the way that we think and behave.
 

Spoilers ahead!

The episode The Entire History of You (Series 1 Episode 3) is set in an alternate reality where people can have a 'grain' implanted to record every moment of their lives and replay memories on a screen whenever they want. However, replaying memories becomes a nightmare, such as for a man who finds out about his wife's affair! Perhaps forgetting is blessing in disguise! I found the episode Crocodile (Series 4 Episode 3) thrilling, and I am sure this will keep you at the edge of your seat! The main character witnesses a road accident and is interviewed by the insurance company as a witness. During the witness interrogation, the investigator uses a memory recaller device to look at the recent memories of her interview partner. As the main character had previously committed a crime, she fears it will be revealed when the recaller scans her memories, so she starts a string of murders to cover up her crime. The best part is the climax-  with the police turning to a pet guinea pig as witness!

 Welcome to neuroscience in the not-so-distant future

The series has made me thinking about aspects of neuroscience, and there are still many unanswered questions. Could the guinea pig or other animals have better memory recall or intelligence than us, human beings? Or could a memory recall device be feasible in the near future? (It would be great to have, especially to quote papers during lab meetings that you have read and forgotten!) Of course, this would necessitate that we first understand how memory is encoded or replayed. Having consciousness transferred to a physical object poses also the big question: Where is consciousness located in the first place? The reality is that we are far from understanding these problems. This is why we have an exciting time ahead of us to learn more about the brain and invent futuristic devices. For those who have not seen Black Mirror, I would definitely recommend it.

Aarti Swaminathan
PhD Student, AG Schmitz





This article originally appeared June 2018 in CNS Volume 11, Issue 2, Brain Invasion

A Day in the Life of Gondi, the Little Toxoplasm

Hey there fellow organism! Yeah, I'm talking to you, bighead. Just because I am only a few micrometers long, doesn't mean you get to ignore me.

Look, I happen to be stuck – in you.
And it's really all your fault. You must have gotten yourself infected by eating uncooked meat or, if you happen to have a cat you probably got a little too close to its feces – either way, you're gross. Do you remember that flu you had a few weeks ago? That was me. Or rather that was your immune system trying to get rid of me, which by the way – rude! Others of my family have infected about half of your sorry population around the globe and most of them were doing fine, no symptoms whatsoever. The way a host should behave, if I may say so. So now, I am crammed into a cyst with who knows how many of my kind and have to lie around semidormant. I don't know if I will ever see the comfy squishy cells of a cat's intestine again, ergo I don't know if I will ever get to sexually reproduce again. Picture that! Sure, I could keep on merrily dividing in you but then your immune system would probably start going all rampage-y again on me, so no thanks. You are just seriously lacking as an intermediary host.

Dividing T. gondii, courtesy of Ke Hu and John M. Murray [1]

 
And this is not me whining – I happen to have been through a whole lot of intermediary hosts: mice, rats, once even a cow. I might be a small, arched parasite but I am capable of surviving in just about any warm-blooded animal. And outside of them, too! In fact, I have been told that I am very resilient to cold climates, thank you very much. Plus, in mice and rats I stand at least a fighting chance to get back into a cat. See, I happen to not only be resilient, highly international and wisely adjusting my proliferation rate so that hosts don't kick me out – I can tweak behaviour of animals who are ten thousand times my size. See, I propagate into my inter-host's brain, I fiddle about a little here and a little there, some hypomethylation of genes that are expressed in the amygdala, a bit of histone-lysine acetylation of astrocytes. And voilà: mice lose their fear of cat urine. Rats even find the smell more attractive! They stop avoiding marked territory and they become altogether less capable of escaping the cat they sniffed out. Isn't that just great?
But humans...pesky. There was a time when getting you eaten by a big cat, say a lion, was a real option. But nowadays you have become so cuddled away and safe with your sweet little overfed furballs. I mean, toxoplasma gondii is no quitter, mark my words! A toxoplasma infection is associated with some neat little behavioural changes in humans: Males show higher levels of testosterone, are more likely to disregard rules. Both of your sexes perform worse in respect to reaction time and concentration. We are associated with higher risks for schizophrenia, bipolar disorder, suicide and traffic accidents.
Still, getting out of a human and back into a cat is hard work. I'm a nice little fella, just wanting to get back to my favourite host.

So. About my being stuck – would you care to get eaten by your cat?

Malika Renz
MSc Student, MedNeuro

Want to know more?
[1]  Hu et al., PLoS pathog 2006
[2] Webster, Schizophrenia bull, 2007
[3] Flegr, Schizophrenia bull, 2007.
[4] Torrey et al., Schizophr res, 2012 
[5]  Hurley et al., J neuropsy clin neurosci, 2012 


This  article won the Best Contribution award for the  issue Brain Invasion  Thanks Malika for such a fun take on a complicated subject!

Like what you see? Interested in contributing? We are always looking for new authors and submission on anything related to the topic of neuroscience. Send us an article, some beautiful shots from your microscope, poems, short stories, critiques, reviews- anything to cns-newsletter@charite.de! 

New Issue Out Now: BRAIN INVASION

The brain is an amazing thing: it allows to think, feel, create and do lots of other less-glamorous things like breathe and digest your lunch. But what's even more amazing is the system that our body has involved to keep it that way. This issue of the newsletter is all about how things can find their way inside our heads- for better or for worse!

 

https://bit.ly/2LwCVRU

First off, have a look at our primer on the different ways in, intracortical implants to poorly cooked food (page 3), and learn more about the body's first line of defense (page 7-8). We also have a first-hand account of a particularly sneaky invader (page 4), as well as clinical reports of foreign objects turning up where they definitely shouldn't be (page 9)! But it's not all bad news! Recent developments have meant that our senses can be augmented (or even repaired, pages 5 and 10), and optogenetics has "illuminated" a whole new realm of experimental possibilities (page 13-14). Are we ready for blending our brains and technology? We have two stories examining the ways authors play with the idea of cyborgs (pages 11-12), as well as providing some thought-provoking watching material (page 7).
Of course, we also have stories from the here and now on campus. What's the point of publishing negative results (page 19)? Are MSc students treated fairly (page 18)? What is it like to work for a big pharma company (page 16)? And, most importantly: what the heck is going on with those yellow buses all over campus (page 21)?

Happy reading, dear readers! We hope that this issue will stick in your head.

Constance Holman and Claudia Willmes
Editors-in-Chief

Neuroscience Podcasts to Seriously Send Those Brain Cells Firing

There’s only so much time one can dedicate to surfing Netflix, listening to Spotify or watching reality TV. At some point, you are adamantly looking for intellectual forms of entertainment. Enter podcasts- the audible version of blogs.

Those with a story-telling flair can keep one indulged for hours. Others that present educational or scientific content keep you intellectually engaged and listening to them are by no means a passive activity. If the podcast’s host has a dulcet tone and knows how to keep things moving, even stuff that you probably couldn’t care less about will become potentially interesting. Which brings us to the million dollar question- with a plethora of science podcasts available, which ones should you listen to? More specifically, are there podcasts that deal with Neuroscientific topics? This was the quest I took two months ago.  Below are some of the Neuroscience podcasts, in no particular order, which might be the answer to your curiosity or intellectual thirst.

1. You are not so smart

Image courtesy: David McRaney, https://bit.ly/2yckkno

Host: David McRaney
Average length: 50-60 min.
How active? : very. uploads content every month, sometimes even twice a month.
The good: Compares different psychology/neurosci topics relevant to current topics and affairs in everyday world. His podcast episodes always leave you feeling sober or humbled by the fact that how subjective, unpredictable and sometimes fickle our human selves can be. Except for a few mins of ads in the beginning and centre, there are no distractions. He also has an excellent way of introducing his guests in that he first gives an overview of the topic and then lets his guest take centre stage. He also doesn’t ramble or try to chime in with his own opinions during the interviews. Plus his voice is deep and lucid which makes it easier to continue listening to him for extended periods of time.
Start where: Tribal Psychology; Selfie; The Dunning-Kruger effect (but really too many good episodes here)
What’s missing? The podcast is overall excellent and you are seriously missing out if you have not heard of YANSS before. Perhaps the only thing you might find lacking would be that this is not, strictly speaking, a Neuroscience specific podcast but borders around Psychology, Pop culture, Neuroscience and Behaviour [1].


2. Brain Science Podcast

Image courtesy: Virginia Campbell, https://bit.ly/1BtSxxs

Host: Ginger Campbell, M.D
Average length: 60 min
How active? : very. technical and less technical content uploaded regularly since 2008
The good: This one is for hard-core Neuroscience enthusiasts. If you are a grad student and are looking for something other than the oft-repeated topics such as reproducibility crisis, women/diversity in STEM than this IS the place for you. There are 100+ episodes available as Dr. Campbell’s podcast has been one of the longest running Neuroscience podcasts to date. She discusses really thought-provoking books that are related to different subdivisions of Neuroscience and has interviewed many leading experts in the field including Drs. Michael Gazzaniga, Christof Koch, Temple Grandin and György Buzsáki to name a few. Listening to Dr. Campbell is like having your extremely well-educated grandma let you in on the intellectual discussions she has with all of her guests.
Start where: Counting Neurons with Dr. Suzana Herculano-Houzel ; John Medina on Aging Well
What’s missing? Some of the older episodes require premium subscription (but full access is possible at 5 bucks a month) so listening to Dr. Koch or Dr. Gazzaniga comes at a small cost. However, you can listen to the more recent episodes uploaded after 2013 for free. All podcasts come with transcripts as well as links to discussed books and papers. Beware though as some of the links may not work due to website revamping [2].

3. Shrink Rap Radio

Image courtesy: David Van Nuys, https://bit.ly/2IxwBMF

Host: David Van Nuys, Ph.D
Average length: 60 min
How active? : very. There are almost 3-4 episodes posted every month.
The good: Dr. Van Nuys also has a talent of making his guests feel at ease and asks thought-provoking questions. There’s also a decent amount of content related to mind-body-soul science if you are into that stuff. Together with the Brain Science Podcast, this is one of the oldest running podcast I could find with quality content.
Start where: Quieting your inner critic and rising above social anxiety with Ellen Hendriksen; The Body of Sex with Sarah Byrden ; The Silent Epidemic of REM Sleep Loss with Rubin Naiman
What’s missing? This is more of a Psychology podcast but has close overlap with Cognitive Neuroscience because of the topics covered. Some episodes are longer than 60 mins so reserve this one for weekends [3].

  4.  A Neuroscientist Explains

Image courtesy: Max Sanderson, https://bit.ly/2Ilyx6M

Host: Daniel Glaser, Ph.D
Average length: 30-40 mins
How active? : Intermittent. Has two seasons out (1^st season: 8 episodes, 2^nd season: 7 episodes); one in 2017 and the other in 2018.
The good: This one’s for all the British accent lovers. The episodes have a very soothing background music so that it literally calmed my anxiety during stressful morning commutes. Quite accessible, user-friendly and the topics are quite relevant if you are interested in Neurosci but don’t know where to start
Start where: A Neuroscientist explains: how music affects the brain; A Neuroscientist Explains: is the internet addictive? ; A neuroscientist explains: how the brain stores memories
What’s missing? The podcast is not very active so if you are looking for interviews and bringing yourself up-to-date with current trends, this isn’t the one [4].

  5. Smart drug smarts

Host: Jesse Lawler (permission pending)

Average length: 40-60 min
How active? : very. Content updated religiously
The good: This podcast has one of the most amusing introduction out of all science podcasts. The episodes are quite fast paced so if you cannot stand slow discussions, go for this one. Lawler is a self-proclaimed science fan boy and is an excellent host. The voice quality is excellent and all the podcast episodes come with detailed transcripts as well as summary notes. The website overall is very decently designed which makes spending time here more fun.
Start where:     Brain Implants – Medical and Beyond with Dr. Brett Wingeier; Head in the Game with Dr. John Sullivan; Cognitive Fallacies with Dr. Richard E. Nisbett ; What are “Fast-Spiking Interneurons”?; Placebo: the Power of the Mind to Heal
What’s missing? Lawler is quite enthusiastic and throws in a lot of slangs and casual phrases so those looking for more serious style discussions may not agree with his hosting style (not that I’m complaining) [5].

  6.  Neurotransmissions

Image courtesy: Joe Schumacher, https://bit.ly/2KJQjlh

Host: Ben Scholl, Ph.D., Joe Schumacher, Ph.D., and Misha Smirnov, Ph.D.
Average length: 30-40 mins
How active? : post content every other month. Haven’t been very active for the last 2 months though.
The good: started by post-docs at Max Planck, Florida, this podcast discusses latest topics in Neuroscience in an almost jargon-free manner. Quite accessible for the general audience in terms of content. Voice quality decent and all of the hosts are quite adept at making things moving and not chiming in too often. The general mood of the podcast is academic style and formal. Go for it if you are into interviews or seeking some inspiration.
Start where: Science writing and life living with Dr. Brett Mensh; Sunposium 2017: Part 2, Technological innovation with Drs. Ed Boyden & Viviana Gradinaru; Live from Sunposium 2017: Part 1, The Value of Scientific Knowledge with Dr. Thomas Südhof
What’s missing? Could be a bit dry at times. Needs some light-hearted humor [6].

7. Neuroscientists Talk Shop

Image courtesy: Neuroscientists Talk Shop, https://bit.ly/2IDc5cJ

Host: various including Salma Quraishi,Ph.D, Alfonso Apicella,Ph.D, Charles Wilson,Ph.D (and others)
Average length: 40 min
How active? : usually post 2-3 episodes every month but have not been very active recently.
The good: started by a group of professors and graduate students at UT San Antonio, this podcast is more hinging on the technical side. Guest scientists are invited in each episode and talk about their research. The questions are more symposium-style and the atmosphere is quite academic and scholarly. If you are looking for some inspiration on someone who is working on a similar topic to yours, maybe look here for some inspiration. Although the podcast has many moderators, the questions never get jumbled up so that everything is easy to follow. Also the podcast has no ads which means no distractions.
Start where: (Interview with) Rusty Gage, PhD ; Ann Graybiel PhD ; Dwight Bergles PhD
What’s missing? Sometimes voice quality not as crisp as you’d like it to be. Could be a bit dry and information-heavy as the time duration is only 40 mins [7].

8. Honourable mentions:
These include Neuroscience podcasts that are no longer active. Neuropod (Nature podcasts on Neuroscience) which ran till late 2015 [8]. The Naked Scientists (Naked Neuroscience) which stopped updating after 2014 [9]. Note that the Naked Scientists podcast on other science disciplines such as Genetics, Astronomy and so on are still regularly updated.

Image courtesy: Chris Smith, https://bit.ly/2IDMkcw

Word to the wise: avoiding mindless media consumption does not mean that your ears have to be glued to scientific podcasts. Cut your poor brain cells some slack and have some time off to digest all the information.

Did we miss any cool podcasts that talk about science and especially all-things-brain? Give us a shout out at cns-newsletter@charite.de about any potential hidden gems that you know.

by Zara Khan, MSc Student MedNeuro

[1] https://bit.ly/2yckkno
[2] https://bit.ly/2jYSpCi
[3] https://bit.ly/2rGYGpK
[4] https://bit.ly/2Ilyx6M
[5] https://bit.ly/2rM38Ui
[6] https://bit.ly/2rNOSuf
[7] https://bit.ly/2IDc5cJ
[8] https://go.nature.com/2rJtyG9
[9] https://bit.ly/2IDMkc

Drug-induced mental disorders: a common reason for concern?

Most psychoactive drugs alter our cognitive and emotional states, but does chronic use implicate a pathological change in our mental condition?

If we chronically alter transmitter pathways, adaptations will certainly take place. Adaptations are expressed during addiction in sensitization and desensitization of transmitter pathways. This leads to an up- or downregulation of receptors and transporters and eventually to tolerance as well as craving when the drug is withdrawn. These adaptations originate out of natural compensation, but leave former drug users with an imbalanced brain chemistry and an increased risk for several mental disorders. Patients with substance disorders are twice as likely to suffer from mood and anxiety disorders (National Institute on Drug Abuse). Basically, all drugs alter dopaminergic regulation and consequently, our motivation and ability to experience pleasure is changed. Several drugs also cause neurotoxicity and can therefore easily lead to permanent damage, e.g. depression after prolonged ecstasy use due to serotonergic cell death. 
Apart from emotional disturbances, the most common drug-induced illness is psychosis; with alcohol (18%), cannabis (13%) and cocaine (18%) being the most common inducers [1]. One could blame everything on 'high risk drugs', yet, for many mental disorders susceptibility genes have been found, e.g. the VAL/VAL variant of the COMT-gene in cannabis users who go on to develop schizophrenia [2]. Other factors, such as food intake, can severely affect mental outcome after chronic drug use, for example vitamin b12 deficiency in alcoholics, which can lead to several mental disorders, including psychosis and depression.
Hence, aside from chronic substance use, our environmental and genetic conditions play a decisive role in the development of long lasting drug-induced mental pathologies.
  
[1] Drake et al., Am J Psychiatry, 2011
[2] Caspi et al., Biol Psychiatry, 2005

By Anne Schwerk, PhD Alumna, AG Neuronal Regeneration and Plasticity (Dr. med. Barbara Steiner)


This article originally appeared in CNS Volume 5, Issue 1, Mental Health Disorders

38% of Europeans affected by mental disease

Arguably, one of the most profound findings of 2011 was an epidemiological report on the mental health status of the European Union. Hans-Ulrich Wittchen and his international team of mental health experts have unraveled striking data on just how extensively disorders of the brain impact European society, and if the trend has been changing over the last three decades.   

With an initial goal to systematically assess the prevalence and burden of neurological and mental disorders in the European Union, experts from each disease category met and combined their data, only to find that it was difficult to segregate prevalence between mental and neurological disorders, due to significant overlap. However, it was possible to assess the burden of mental and neurological disease separately, when expressed as disability adjusted life years. Previous knowledge on this subject has been sparse - the World Health Organization reported an estimated 13% of global health burden to be from mental disorders. The World Mental Health Survey quotes that one in three adults suffers from a mental disorder.

Mental and Neurological Disorders Come to the Forefront: Significant Health Burden on Society

Wittchen and colleagues set out to sample all of the EU countries as well as Norway, Iceland, and Switzerland. The team combined retrospective studies, consistent reanalyses of existing epidemiological datasets and supplementary survey data from national experts to gather the best possible comprehensive dataset. 19 epidemiological panels were dispatched and at least one international expert was recruited per diagnostic group. Data was collected as far back as 1980, when the first diagnostic criteria were published on an international level (Diagnostic and Statistical Manual of Mental Disorders (DSM) and International Statistical Classification of Diseases and Related Health Problems (ICD)).
The results were startling: 38% of all Europeans are affected by disorders of the brain. Combined, mental and neurological diseases comprise Europe's largest disease burden, in terms of disability adjusted life years. The highest proportion of this burden was due to anxiety disorder, unipolar depression and insomnia.
Previously, Wittchen and colleagues had published a similar report in 2005, where the numbers were significantly more conservative, citing that 27% of the EU population are affected by mental disorder. However, this study produced a much more restrictive estimate due to age restrictions of the sample (only adults and not kids nor elderly were included), and a much more limited set of criteria for mental disorders. This time around, the team decided to get an unrestricted estimate regardless of age range or disease type.

Wittchen et al., Eur. Neuropsychopharmacol, 2011
Wittchen and Jacobi, Eur. Neuropsychopharmacol, 2005
World Health Organization, The Global Burden of Disease, 2004 Update (WHO, 2008)


By Gina Eom, Alumna MedNeuro 

this article originally appeared in CNS Volume 5, Issue 1, Mental Health Disorders

Empirically Aesthetic? MPI Researchers Weigh In

It's fascinating to read about big concepts like philosophy and beauty, but what is it like to study them in your daily job? Malika Renz sat down with researchers from the Max Planck Institute for Empirical Aesthetics to find out.

Pauline Larrouy-Maestri

Pauline Larrouy-Maestri, you have a very diverse background – can you tell us how you got into neuroaesthetics?
Yes, I studied music, psychology and pedagogy and worked as a musician and a speech therapist. My PhD was in cognitive psychology, on the singing voice which is of course linked to aesthetics. But aesthetics wasn't my main focus then – it's more of a means of looking at how people interact with their environment, at auditory perception and processing. I've been working on this as a post-doc here at the MPI for 3 years now.

How do you start with something as vague and mysterious as beauty and end up learning about perception and processing mechanisms?
Suppose you start with the question: what makes something beautiful? Is it the same as being somehow correct? Or interesting? Recently, we've been working on pitch accuracy, so let's take that as an example. Beautiful singing voices or melodies are often associated with being "correct". Everyone can hear if a performance is in or out of tune – musicians, non-musicians, male, female, young and old – people usually agree on this. So what is it that makes all of us feel that one tone is correct and the other is not? It's hard to put a label on this, it just sounds right or wrong. Somehow, people must become sensitive to the criteria for a correct melody without ever being aware of it! And we know this holds true not only for music but also for other domains – we learn rules and we apply them to make an aesthetic judgment without even noticing.

But if we don't even notice it – how are we learning those rules?
The brain is made for taking in stimuli and building rules, and thus knowledge from it. It's similar to how children learn a language, a totally implicit process. To understand language you have to parse the auditory signal – you need to cut it into sensible units and concatenate them in a meaningful way. The same parsing and integrating of course happens in music appreciation as well and it is this process which I am interested in. Aesthetics is my vehicle to study how we learn auditory processing, what the minimal units and the rules of meaningful integration are.

How can you research music appreciation in the lab?
Me, I am doing psychophysics: I manipulate stimuli, I invite people to the lab and ask them to listen to these stimuli. We change single features of tones and ask something like “Which of these sounds is more in tune?”. The resulting data can tell us what differences are perceived and what magnitude of change is needed. That alone reveals a lot about the structure of sounds, its components and their relative importance. This was how we found out that the smallest meaningful units are not single notes –  it's the beginning and the end of a a note that matters. Once you find these units and confirm their discerning value, you can play with them: find out how the changes influence the perceived agreeableness or pitch accuracy. And whether people even agree on the direction of effect of a specific parameter.

Pardon my impoliteness, but apart from being fascinating, what use is there in all this?
Aesthetic appreciation of course is very fundamental. Many things are related to what you see and hear, all around you. Interaction with people is about tastes, preferences, about your appreciation of the environment. We all function with that all the time. But we don't understand the processes behind it very well: we know that the pleasure circuitry is based on automatic processes. For perceiving something as beautiful, however, indirect pathways, such as mediation by thought, are needed. Simply knowing how perception works has a clinical application. If someone has a speech impairment or a difficulty to understand language, is it because they cannot parse? Cannot concatenate? Didn't learn the appropriate rules? As soon as we have a working model we can tick which box is malfunctioning and focus training or treatment there.

To save the best for last: what was your personal research highlight?
I showed that we are all musicians. Let me explain. For decades, we had in the scientific literature a separation between musicians and non-musicians. It is categorical, but the idea has been around for a while – and it's nonsense! Take an opera performance. Who goes to the opera? No one does! Only a very small part of the general population, mostly educated people with a musical background or interest. And musicians agree to a very great extent on their judgment of what makes a beautiful opera voice. But here is what I found: people who have no idea what an opera voice is or should be apply the same criteria and come to the same conclusions. So, without ever going to the opera, without any explicit input, we build a representation that creates a link – between you and me, between people who are privileged enough to enjoy operas and those who aren't. Our learning mechanisms are fundamentally the same and they take whatever they can get from the environment.


 The interview was conducted by Malika Renz, MSc Student MedNeuro

Does Beauty Lie in the Face?

As the saying goes, ‘beauty is only skin-deep’. However, many times we cannot help but fall for an attractive face: the first impressions of a person do create an impact on our minds. What is considered ‘beautiful’? Are there features of faces across cultures that people find more attractive?

Facial Symmetry

According to researchers, a face is perceived as beautiful if it is symmetrical and represents the average traits of the population. Our eyes recognize symmetrical faces with similar proportions on left and right side of the face. The quest to define a golden standard for a facial feature - for example, the size or shape of the eyes or lips - dates back to antiquity. The Ancient Greeks believed that the essence of beauty lied in the golden ratio of 1:1.618. More recently, researchers have discovered that people find a female face attractive when the distance between the eyes is just under half of the width of the face. They also found that the eye-to-mouth distance should be just over one-third of the height of the face. These two ratios have been termed as the ‘golden ratios’, which correspond to that of an average face [1].

Example of faces with different length and width ratios. Boxes mark the optimal length and width ratios that people found attractive [1].

 

What is the reason behind the choice of such features? This can be explained by two existing theories: one is an evolutionary aspect where humans tend to choose healthy mates with physical characteristics resembling the average population. The other is a cognitive aspect where, due to repeated exposures, we tend to prefer prototypical facial features which are easier to process.

Golden ratio: can beauty be quantified? 

So, are facial preferences based on nature or nurture? Do we have a preference for certain faces as babies? The answer seems to be: yes! Babies of 2-3 months tend to look at attractive faces for longer time than unattractive ones [2]. The perception of attractiveness is also affected by familiarity: Hazda people, hunter-gatherers from Tanzania who have not been exposed to European faces, found the average face of a Hazda more attractive than an European face [3]. But spatial aspects of the face are not the only determinants of attractiveness - sexually dimorphic features like full lips and longer eyelashes also influence what people find attractive [1 ].

The Power of a Smile

A smile has more powerful influence on people’s perception than facial features or makeup, according to psychologists. People with genuine smiles were seen as healthier and more attractive by virtue of being optimistic and cheerful than people with blank expressions [4,5]. Thus, the secret to healthy appearance and being attractive? Smile!

For the evolutionary basis of beauty, check out Helge's article on page 5. Given the fact that there is an innate bias inside all of us towards 'beautiful' faces, it is even more important for us to think twice before making judgements on other people based just on their appearances!

How an average American woman will look like in 50 years
(Courtesy: National Geographic)

What will future humans look like?

It has been predicted that globalization, cultural diffusion and interracial marriages will eventually homogenize the human population, averaging out more and more people's traits such as hair, eye color, facial features, and eye shape. Dominant traits will be expressed more than recessive traits (which need not one but two copies of the gene to be expressed). In other words, we are going to become a huge amalgamated race!

by Aarti Swaminathan, PhD Student AG Schmitz

 [1] Pallett P.M, Link S, and Lee K. Vision Res. 2010.
 [2] Hoss R.A. and Langlois J.H. The Development of Face Processing in Infancy and Early Childhood: Current Perspectives. 2003.
 [3] Apicella C.L et al. Perception, 2007.
 [4] Golle et al. Cognition and Emotion, 2013
 [5] Jones A.L et al. Visual Cognition, 2017.