Helix, Winter 2017-2018

Helix

Milton Academy’s Science Journal

Winter 17-18

Helix Staff Helix Board 2017-18

Editors-in-Chief: Max Hui and Kevin Lu Managing Editor: Christine Flatley Senior Editors: Patrick Huang and Catherine Gallori Layout Editor: Emma James Faculty Advisor: Linde Eyster

Zaki Alaoui Kiran Biddinger Ryan Choi Ariane DesRosiers Desmond DeVaul Christine Flatley Catherine Gallori

Helix Writers Alexandra Galls U.G. Gurol Patrick Huang Zan Huang Max Hui Emma James Leo Jin

Kate Jones Grace Li Daniel Little Kevin Lu Alexander Shih Charles Sloane Antoine Wiley

We would like to thank the following people for their contributions to Helix:

Ms. bargar, Mr. Bingham, Mr. Hales, Ms. Locke, Mr. Moy, Ms. Pries.

Helix is Milton Academy’s one and only scientific journal, written by and for Milton students on a range of STEM topics. We strive to help students better share their passion and knowledge in the sciences with the entire Milton community.

Article Topics

4 MicroRNA Biomarkers by Alexandra Galls 6 Drought Recovery by Patrick Huang 8 Photos by Linde Eyster

10 Artificial Human Brain by Ryan Choi

12 Self-Replicating Machines by Zan Huang 14 Brain Development by Kelly Han

Cover image: Falvon Heavy, curently the most powerful rocket in the world, takes off from Pad 39A -- the same facility used by the moon rocket Saturn V. Official SpaceX Photos. Falcon Heavy Demo Mission. Photograph. Flickr. February 6, 2018. https://www.flickr.com/photos/spacex/40126461851/.

MicroRNA Biomarkers

for Heart Failure and Other Diseases

by Alexandra Galls

As the human genome was being sequenced around the turn of the millennium, scientists began to realize that less than 2% of the genome was DNA coding for proteins (1). Protein-coding DNA has its effects by serving as a template for the creation of messenger RNA (mRNA), which is then translated into functional protein. DNA that does not lead to the translation to a protein through mRNA was initially thought to be “junk” DNA that did not carry meaningful information (2), but scientists now know that a significant amount of the genome serves as a template for “non-coding RNA,” or RNA that does not code for proteins (3).

A very important type of non-coding RNA is microRNA (miRNA): small non-coding RNA molecules that are involved in a wide range of cellular processes (3). Many miRNAs limit gene expression through impeding mRNA molecules’ DNA-translation process (4) (Figure 1). Relatively short in length compared to many RNA molecules, miRNAs

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are evolutionarily conserved across species, suggesting the possibility that the molecules participate in a range of important genetic pathways, including those involved in disease prevention (5).

As miRNAs play an important role in gene regulation, the ability to identify one’s miRNA composition can be very useful as a biomarker (indicator) for cardiovascular disease, cancer, and hepatitis C, among other health conditions (6, 7). For instance, levels of a specific miRNA (miR-185) were significantly higher among individuals who had heart failure (sample size of 44) than among healthy individuals (sample size of 15) (3). Higher levels of particular miRNAs in patients with heart failure may reflect miRNAs’ role in cardiac hypertrophy (enlargement) and apoptosis (cell death) (7). In addition, miRNAs have been linked to cancer; for instance, another specific miRNA (miR-9) has been found to be associated with the spread of cancer from a primary tumor to secondary locations in the body (4). In both diseases, miRNAs could be used in diagnosis, as they are found in different proportions

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among healthy and non-healthy individuals. Along with miRNAs’ diagnostic value, they are also beginning to be used in treatment; clinical testing of the use of miRNA therapy in the treatment of cancer and hepatitis C has begun (7).

While miRNAs can be extremely useful for both detection and treatment of disease, the use of miRNA information is complicated by the question of the bodily source from which the sample should be taken; even within the blood of a single individual, miRNA profiles may not be identical in different samples, such as only plasma (the colorless fluid in which blood cells are bathed) versus whole blood (including plasma and blood cells), and one may provide a more useful profile (5, 8). If miRNA profiles are to be used as biomarkers for disease, being aware of differences between the profiles and determining which profile is optimal for diagnosing different diseases is crucial. To compare the two profiles, scientists examined samples of both plasma and whole blood from thousands of participants and compared the

miRNA composition in plasma versus whole blood (5). The results of the study indicated that samples from plasma and whole blood were not consistently comparable. While some specific types of miRNA displayed statistically similar presence in both plasma and whole blood, most types did not (5). Greater specificity about miRNA source (for instance, plasma versus whole blood) in the future may help to make miRNA detection as useful as possible.

Clearly, DNA segments that generate miRNAs can have crucial impacts on organisms despite the fact that such segments do not code for

Figure 1. miRNA binds to mRNA, preventing its translation into protein. source: https://directorsblog.nih.gov/2013/11/26/microrna-research-takes-aim-at-cholesterol/

proteins. However, the idea that no DNA is “junk” DNA may be too strong, for even with the discovery of miRNAs and other non-coding RNA molecules, uses have been

discovered for only a modest fraction of the vast expanse of the human genome (9). The mystery of many DNA segments that do not code for proteins remains to be solved.

Sources Cited:

1) Wilusz, J. E., H. Sunwoo, and D. L. Spector. "Long 5) Shah, R., K. Tanriverdi, D. Levy, M. Larson, M. Gerstein, E. Mick, J. Rozowsky, R. Kitchen, V. Murthy, E. Noncoding RNAs: Functional Surprises from the RNA World." Genes and Development 23 (2009): 1494-Mikalev, J. Freedman. "Discordant Expression of Circulat1504. https://www.ncbi.nlm.nih.gov/pmc/articles/ ing MicroRNA from Cellular and Extracellular Sources."

PLOS ONE (28 April 2016), 1-6. http://journals.plos.org/ PMC3152381/.

2) Zhen, Y. and P. Andolfatto. "Methods to Detect Se- plosone/article?id=10.1371/journal.pone.0153691. lection on Noncoding DNA." Methods Mol. Bio. 856 6) Tijsen, A., E. Creemers, P. Moerland, L. de Windt, A. (2012): 141-159. https://www.ncbi.nlm.nih.gov/pmc/ van der Wal, W. Kok, Y. Pinto. “MiR423-5p As a Circulating Biomarker for Heart Failure.” Circulation Research articles/PMC3725466/.

3) Ellis, K. A., V. A. Cameron, R. W. Troughton, C. M. (April 2, 2010), 1035-1039. http://circres.ahajournals.org/ Frampton, L. J. Ellmers, and A. M. Richards. "Circu- content/106/6/1035.

lating MicroRNAs as Candidate Markers to Distin- 7) Wong, L., J. Wang, O. Liew, A. Richards, and Y.-T. Chen. guish Heart Failure in Breathless Patients." European "MicroRNA and Heart Failure." International Journal of Journal of Heart Failure 15 (2013): 1138-1147. http:// Molecular Sciences 17 (2016), 1-31. https://www.ncbi.nlm. onlinelibrary.wiley.com/doi/10.1093/eurjhf/hft078/ nih.gov/pmc/articles/PMC4848958/. full.

8) Grasedieck, S., A. Sorrentino, C. Langer, C. Buske, H. 4) Ma, L., J. Young, H. Prabhala, E. Pan, P. Mestdagh, D. Muth, J. Teruya-Feldstein, F. Reinhardt, T. T. Onder, S. Valastyan, F. Westermann, F. Speleman, J. Vandesompele, and R.A. Weinberg. "miR-9, a MYC/ MYCN-activated MicroRNA, Regulates E-cadherin and Cancer Metastasis." Nat Cell Biol. 12(3) (March 2010), 247-256. https://www.ncbi.nlm.nih.gov/pmc/ articles/PMC2845545/.

Dohner, D. Mertens, and F. Kuchenbauer. "Circulating MicroRNAs in Hematological Diseases." Blood, 121 (20 June 2013), 4977-4984. http://www.bloodjournal.org/content/121/25/4977.long.

9) Zimmer, C. “Is Most of Our DNA Garbage?” New York Times Magazine (5 March 2015). https://www.nytimes. com/2015/03/08/magazine/is-most-of-our-dna-garbage. html.

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Drought Recovery: Problems Under the Surface

by Patrick Huang

Whether consumed for drinking or irrigation, water is a precious and important resource that some communities lack. After enduring a severe drought (a period when dry conditions negatively impact a region’s water supply) that persisted for more than five years, California

By investigating California’s drought, we may discover that the less visible effects of drought are the ones that have longer lasting impacts.

While droughts certainly deplete the water resources found on the Earth’s surface

Fig. 1. Due to heavy rainfall, water overflowed from the Oroville Dam in California in 2017. https://upload.wikimedia.org/wikipedia/commons/3/3b/Oroville_Emergency_Spillway_Carrying_Water.jpg

received above-average amounts of precipitation in the early months of 2017, enough to overflow dams (1) (Fig. 1).

With some reservoirs (artificial lakes that store water) and snow accumulation in the Sierra Nevadas reaching higher than historic levels, California’s water supply shows signs of recovery from drought (1).

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(water stored in reservoirs or snow deposited in the mountains), droughts also deplete groundwater, water that is naturally found underground (1, 2). Groundwater accumulates when water seeps into the ground and fills in the cracks between rocks and soil (1, 2). A collection of groundwater, sometimes found

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in large volumes, is called an aquifer; people can access aquifers by drilling wells down into the earth (1, 2). To increase the chances that crops stay healthy during a particularly dry season, farmers rely on groundwater for irrigation (2).

When reservoirs dry up during a drought, farmers consume more groundwater than in a non-drought season, so aquifers may be depleted at a rate faster than they are naturally replenished (3).

In 2014, Governor Brown issued a drought State of Emergency once it was realized that California had passed a dangerous threshold: the state’s rivers and reservoirs dipped beneath record lows (4). To compensate for the diminishing surface water supply, farmers in California drastically increased their usage of groundwater. In a drought, groundwater supplies 60% of the state’s water, as opposed to 40% in years of average precipitation (5).

Over-pumping groundwater has serious and permanent repercussions. In the soil, clay and silt sediments that are normally spread out by water are layered into more compact stacks as more water is pumped out (6). This rearrangement can cause the ground to sink (Fig. 2), and the size of an aquifer may decrease permanently as a result (6, 7). These changes in terrain may open new entry points for contaminants such as fertilizers, pesticides, and industrial pollutants to enter into groundwater; if

these compounds become concentrated in these compacted aquifers and are left untreated, the groundwater can no longer be used for drinking or irrigation (8). The water needed to support California’s agriculture industry, the largest in the United State by sales, exacerbates these issues (9).

Therefore, many aquifers and wells in California can no longer be used (8).

Despite the exceptional amount of rainfall that has helped replenish Californian reservoirs, the state’s aquifers and groundwater supply are still in a dire state. In the last 60 years, the Central Valley area that holds California’s largest supply of groundwater has been expended by an amount that can supply about eight years’ worth of water to every Californian resident (10). Although aquifers will take at least few years, perhaps

even decades, to naturally replenish (1,2), individuals are trying to find solutions to groundwater depletion.

Some farmers have deliberately flooded their fields so that river-sourced water can naturally seep into the ground and replenish groundwater reserves (11). Scientists are now looking at how this type of deliberate flooding affects crops to see if this method of “recharging” aquifers by storing water underground for future use is viable (11).

The effects of a drought, especially one of such a large magnitude in California, cannot be easily reversed by one season’s worth of rain.

We must acknowledge the price we pay each time we withdraw groundwater from an aquifer. While individual water conservation efforts can have an impact, further government

Sources Cited:

Fig. 2. Serious overconsumption of groundwater can lead to large fissures in the ground after an aquifer collapses. https://water.usgs.gov/ edu/pictures/full-size/ landsubsidence-lakelucern-large.jpg

action is likely needed to save California from its drought. Our access to water is dependent on our ability to conserve and protect our groundwater resources both in our communities and in the global context. We should not only change our own water usage habits but also demand our leaders to act on this important issue.

7) Than, K. “Groundwater Over-pumping Is Reducing San Joaquin Valley’s Ability to Store Water.” Stanford School of Earth, Energy & Environmental Sciences. 12 Apr. 2017. Web. 5 Feb. 2018. <https:// earth.stanford.edu/news/groundwater-over-pumping-reducing-san-joaquin-valley%E2%80%99s-ability-store-water>

1) “California Drought.” California Water Science Center. N.d.

Web. 5 Feb. 2018. <https://ca.water.usgs.gov/data/drought/> 2) Cho, R. “The Growing Groundwater Crisis.” State of the Planet. Columbia University, 3 Aug. 2015. Web. 5 Feb. 2018. <http://blogs.ei.columbia.edu/2015/08/03/the-growing-groundwater-crisis/> 3) Alley, W.M., Reilly, T.E., and Franke, O.L. “Ground-Water Development, Sustainability, and Water Budgets” Sustainability of Ground-Water Resources. U.S. Geological Survey Circular 1186.

1999. Web. 5 Feb. 2018. https://pubs.usgs.gov/circ/circ1186/ html/gw_dev.html 4) Brown, E. G., Jr. “Governor Brown Declares Drought State of Emergency.” State of California, 17 Jan. 2014. Web. 5 Feb. 2018. <https://www.gov.ca.gov/news.php?id=18368> 5) Gleick, P. “The Untapped Potential of California’s Water Supply: Efficiency, Reuse, and Stormwater.” Pacific Institute, June. 2014. Web. 5 Feb. 2018. <http://pacinst.org/app/uploads/2014/06/ca-water-capstone.pdf> 6) “Land Subsidence: Cause & Effect.” California Water Science Center. N.d. Web. 5 Feb. 2018. <https://ca.water.usgs.gov/land_ subsidence/california-subsidence-cause-effect.html>

8) Moran, T., Choy, J., and Sanchez, C. “Understanding California’s Groundwater.” Water in the West. Stanford University, 9 Sept. 2014.

Web. 5 Feb. 2018. <http://waterinthewest.stanford.edu/groundwater/overdraft/> 9) “Agricultural Production and Prices.” United States Department of Agriculture, 5 May 2017. Web. 5 Feb. 2018. <https://www.ers.usda. gov/data-products/ag-and-food-statistics-charting-the-essentials/ agricultural-production-and-prices/> 10) Faunt, C.C. “Groundwater Availability of the Central Valley Aquifer.” U.S. Geological Survey Professional Paper 1766. 2009. Web. 5 Feb. 2018. https://pubs.usgs.gov/fs/2009/3057/ 11) Charles, D. “As Rains Soak California, Farmers Test How To Store Water Underground.” NPR, 12 Jan. 2017. Web. 5 Feb. 2018. <http://www.npr.org/sections/thesalt/2017/01/12/509179190/ as-rains-soak-california-farmers-test-how-to-store-water-underground>

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Science Photos Taken by Linde Eyster

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Loihi: The Artificial Human Brain

by Ryan Choi

Throughout the past century, technology development has exponentially grown to help improve our lives. For instance, technology can allow us to start perfecting skills such as taking scientific data in manufacturing and in dangerous environments.

At this rate, we can perfect anything we want to, including ourselves. We can accomplish these kinds of perfections using what is known as artificial intelligence.

Artificial intelligence is a type of technology that performs computations to mimic our human behavior (1). This innovative technology can be easily found right next to you! The smartphones with virtual assistants like Siri, Google Now, Cortana, and Bixby are all examples of artificial intelligence (2). Just like a personal assistant, these virtual assistants help you in scheduling meetings, making wake-up alarms, reminding

you, and functioning to your liking (2).

In the rising prominence of artificial intelligence, Intel has developed an artificial intelligence prototype chip that works like a human brain called Loihi (3). This kind of mechanism, called neuromorphic technology, is based on how we as humans learn and make decisions (3).

Loihi is a chip that relies on this mechanism to function like a

Figure 1: Imagine being able to check on your newbornâ&#x20AC;&#x2122;s temperature and heart rate through a phone! dailymail.co.uk/sciencetecharticle-4924826/Intel-develops-Loihi-AI-chip-workslike-human--brain-html

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human brain (4). As a basis of AI systems, Loihi uses a neural network, which is a network that is based on the human brain and nervous system (5). Loihi has “1,024 artificial neurons, or 130,000 simulated neurons with 130 million possible synaptic connections” (4). This similarity to the brain allows the chip to send info by using neuron signals that send messages towards one’s brain and then understand the combination of neuron signals to learn certain tasks (4).

A significant feature of Loihi is that its neurons can be signaled whenever, instead of being regulated like a clock in different AI chips (4).

Moreover, the freedom of the neurons allows the brain cells to work together in the brain’s neural network, and thus this advantage allows Loihi to learn by itself without any assistance (3). When compared to a regular chip, not only is this chip different in structure but also different in energy efficiency (1000 times more) (6). With this

advantage, chips like Loihi will be able to be more independent when it is used especially with phones or laptops (6). Intel says that Loihi has more than enough potential to improve automotive and industrial applications and even personal robots (4).

Although this technology is not yet finalized for the public, Intel is planning to distribute this prototype chip in 2018 to select universities and research institutions that primarily study artificial intelligence (4). Intel’s goal for distributing the chips to universities and research institutions is to assess the chip’s practical performance for different kinds of AI applications so that Intel can further improve development (4). Intel Labs says that AI technology like Loihi will continuously further push the potential of AI technology as a whole, and thus the world will sufficiently benefit from this new self-learning technology chip (3).

Artificial intelligence will soon become a major part in our lives as the world approaches its technology future. Especially for Loihi, systems with this technology allow us to discover many possible different and new applications (3). For example, teaching this chip the ‘normal’ conditions of a newborn baby could enable us to track the changes from this norm so that parents can comfortably care for their baby (Figure 1) (3).

However, these applications are not limited to personal use but can also be applied to areas like cybersecurity (3). By teaching cybersecurity systems of what a ‘normal’ condition would be, the system would be able to distinguish what is abnormal, easily track down unusual activity in its data, and identify whether that activity is a hack or a breach (3). With all of these applications in mind, the technology of Loihi would revolutionize our lives of the future.

Sources Cited

4. Dent, Steve. “Intel unveils an AI chip that mimics the human brain.” Engadget, edited by Steve Dent, 26 Sept.

2. Albright, D. “10 Examples of Artificial Intelligence 2017, www.engadget.com/2017/09/26/intel-loihi-neuromorphic-chip-human-brain/. Accessed 13 Feb. 2018.

You’re Using in Daily Life.” Beebom, edited by Dann Albright, 26 Sept. 2016, beebom.com/exam5. Rouse, M. and J. Burke. “Definition Neural Network.” ples-of-artificial-intelligence/. Accessed 13 Feb. 2018. SearchNetworking, searchnetworking.techtarget.com/ 1. “Artificial Intelligence.” Merriam-Webster

3. Collins, T. “Intel unveils an AI chip that works like a human brain to get smarter over time using learned experiences.” DailyMail, edited by Tim Collins, 27 Sept. 2017, www.dailymail.co.uk/sciencetech/article-4924826/Intel-develops-Loihi-AI-chipworks-like-human-brain.html. Accessed 13 Feb. 2018

definition/neural-network. Accessed 13 Feb. 2018.

6. Vincent, J. “Intel investigates chips designed like your brain to turn the AI tide.” TheVerge, 26 Sept. 2017, www.theverge.com/2017/9/26/16365390/intel-investigates-chips-designed-like-your-brain-to-turn-the-ai-tide.

Accessed 13 Feb. 2018.

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Self-Replicating Machines and the Game of Life

by Zan Huang

Faced with the task of making Mars habitable, John von Neumann, one of the founding fathers of computability and computer science, experimented with a potential solution even as early as the 1940s. Mars’ atmosphere lacks oxygen and does not offer protection for potential human settlers against cosmic radiation, which is highly dangerous to

living organisms because it can damage DNA. In a stroke of genius, he conceptualized a theoretical machine that would self replicate using only the materials found on Mars. As a byproduct of the replication, the machine would generate enough carbon dioxide for the atmosphere to sustain plant life that would create breathable oxygen, making

human colonization possible.

(1) Through a revolutionary paper compiled after his death, “Theory of Self-Reproducing Automata,” the field of self replication was born.

To understand what self replicating machines are, one must first take a look at a Game of Life, a chaotic mathematical formula invented by John Conway.

Conway’s Game of Life is not just fascinating because of its ability to create and contain self replicating machines, but also because it houses seemingly intelligent life forms, computers, and artificial petri dishes. (2)

Figure 1 Represents the rules and outcomes for Conway’s Game of Life. These are the representations for how one pattern changes into the next. A filled box is called a living cell. An empty box is called a dead cell. http://www.math.cornell.edu/~lipa/mec/lifep.png

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The rules of Life are simple.

In order to understand them imagine an infinite or a large finite grid of empty boxes. It is completely up to the player to fill any of the boxes to their own discretion. After filling the boxes accordingly, the player no longer has control over the squares and instead any further change to the grid will be based on several rules (Fig I):

Rule I. A cell that is alive remains alive only if it has at least two but less than four living neighboring cells.

Rule II. If a cell is alone with one or less living neighbors, it dies.

Rule III. A dead cell can resurrect if it has three live neighbors.

Rule IV. If a cell has more than three neighbors, it dies from overpopulation.

Although the rules may seem simple, the Game of Life is mathematically able to compute or simulate every finite function, an attribute known as Tur-

ing Completeness. In fact it is possible to construct a functioning computer inside the Game of Life that runs a program that simulates the Game of Life. So what does all of this “Life” have to do with self replicating machines? Since the Game of Life is Turing Complete, any machine or physical behavior can be rebuilt using the four simple rules. That feature allows the world inside the Game of Life to support self replicating machines. In fact when John Conway was creating the Game of Life, he made sure it had the potential to support Von Neumann Universal Constructors, which is another term for self replicators. (3, 4) However, the potential for a self replicating machine to exist in the Game of Life does not mean it is easy to construct one. The potential to support self replicating life is the most the Game of Life relates to the idea of “Self Replicating Machines.” There was not a single self replicating organism found in the Game of Life until 2010, which is both remarkable because of preexisting mathematical formulae for self replicating machines and unremarkable because self

Sources Cited 1.) Neumann, J.V, and Arthur W. Burks. Theory of Self-Reproducing Automata. University of Illinois Press, 1966.

2.) Lipa, Chris. “Conway’s Game of Life.” Conway’s Game of Life’, Cornell University, 17 Nov. 2017, www.math.cornell.edu/~lipa/mec/lesson6.html.

3.) Rendell, Paul. “A Fully Universal Turing Machine in Conway’s Game of Life.” A Fully Universal Turing Machine in Conway’s Game of Life, Paul

replicating machines are extremely complex. (5) Even with a modern computer, it would take several minutes to simulate the replication of a single Von Neumann machine given the amount of steps required to produce a working mathematical artificial DNA and device (1).

Throughout technological history, there was always the issue of a lack of automation. I imagine new mathematical insights found within the Game of Life may harbor a plethora of potential technological developments.

Self regulating colonies on other planets may not only be feasible in the future, but also a daily reality. The existence and functionality of self replicating machines also plays its importance in the field of programmable matter, where one could design a product and have matter containing self replicating properties reconstruct the design by itself. There is huge potential for these machines regardless of the current problems that could be solved using them. The idea of self replicating machines could very well carry the human species into a more technologically advanced age.

Rendell, 27 Mar. 2011, rendell-attic.org/gol/fullutm/index.htm.

4.) Stanford. “a discussion of The Game of Life.” Game of Life, Stanford University, 20. Jan. 2018, web.stanford. edu/~cdebs/GameOfLife/.

5.) Aron, Jacob. “First replicating creature spawned in life simulator.” New Scientist, New Scientist, 19 June 2010, www.newscientist.com/article/mg20627653-800first-replicating-creature-spawned-in-life-simulator/.

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Critical Periods in Brain Development

by Kelly Han

Chances are since you were Evidence supports that these patients all lost their a young child, you have vision has a specific critical vision after the critical period, been trying a whole range of development period. allowing them to regain full activities such as playing the Researchers, who published vision because their brains violin or learning a foreign their study in the journal had already established the language, but have you noticed Ophthalmology (2), restored connections required for visual as you have gotten older, sight in patients who suffered interpretation (5). acquiring new skills has become from Tersonâ&#x20AC;&#x2122;s syndrome, a increasingly difficult? This occurrence happens because you are gradually reaching the end of the critical periods for achieving each of these skills.

Critical periods are stages during a lifespan when the brain is more sensitive and adaptable to new information and stimulation.

Evidence suggests that critical periods exist in one type of mechanism that guides brain development: experienceexpectant plasticity, which refers to neural connections created in all humans receiving cognitive, speech, and motor stimuli, which are events that Figure 1: Sensitivity of a childâ&#x20AC;&#x2122;s ability to learn for various situations elicit a sensory or behavioural during the first seven years of life. Peaks indicate critical periods. response in an organism, from a Source: http://take30.gpei.ca/learn-more/ typical environment (1). Speech and vision are both examples hemorrhage in the eye that Many scientists argue for the of experience-expectant blinds the patient (3). If these critical period hypothesis, mechanisms. The brain expects patients had experienced the which states that there is a certain stimuli, which are trauma before the proposed critical age, before puberty, essential during the limited critical period for vision, from when one must learn language, critical periods of development birth to around age three (refer and after puberty, learning for healthy maturation (1). to figure one) (4), they would speech fluently becomes Otherwise, the ability to fully have disrupted the wiring of the increasingly difficult to nearly develop particular functions, brain to interpret visual stimuli, impossible (6). Feral children, such as language and sight, is leading to possible medical people that have been isolated lost forever (1). complications. However, from human contact at a young Page 14

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age due to neglect or abuse, inhibiting their development of social skills and grasp of language, support the critical period hypothesis (7). Genie Wiley was a feral child that had not been exposed to any language for the first thirteen years of her life and even after treatment, was unable to speak in grammatically correct sentences or use language meaningfully (8,9). Researchers continue to examine critical periods with a goal of helping people like Genie. The idea of extending critical periods, or reopening them, could dramatically benefit Genie’s recovery.

Furthermore, prolonging critical periods could also benefit people who do not receive essential social stimuli during the specific ages for development. For example,

the Turpins, a family living in Southern California, seldom allowed their thirteen children to venture out of the house, depriving the children of social stimuli from being exposed to various social situations that they could experience only outside their house (10). A neighbor reported that she once spoke to the children around Christmas time in 2015; she complimented the children on their Christmas decorations, and they allegedly froze and did not say a word (10). The parents were ultimately arrested in early 2018 and the children were taken to a medical center for treatment (10). With the prospect of increasing critical periods, doctors could better understand how to help the Turpins, and other people who may experience a similar social ineptness, adjust to society and learn how to handle social

interactions.

Most psychologists agree that the initial stages of a child’s life are prominent in development and learning. Psychologists believe children must receive stimuli during their critical periods with respect to vision and language (1). However, a lack of certain stimuli, such as contact with other children or the presence of toys and books, during these times may not always be detrimental to a child’s development. Continued research about critical periods is hoping to discover whether or not critical periods can be extended with the goal of helping people compensate for a lack of stimuli, such as those born blind or deaf, allowing them to fully recover vision or speech.

Sources Cited (1) Spinks, S. “The ‘First Years’ Fallacy.” Frontline, WGBH Educational Foundation, www.pbs.org/wgbh/pages/ frontline/shows/teenbrain/science/firstyears.html.

(2) Caughill, P. “A New Surgery Can Give Legally Blind People 20/20 Vision.” Business Insider, Business Insider, 13 Dec. 2016, www.businessinsider.com/surgery-blind2020-vision-2016-12.

S0896627307007581.

(6) “The Critical Period Hypothesis on Language Acquisition Studied Through Feral Children.” News Activist, 19 Nov. 2013, www.newsactivist.com/en/articles/knowledge-media/critical-period-hypothesis-language-acquisition-studied-through-feral.

(7) “Feral Children.” Good Therapy, 17 Jan. 2018, www.goodtherapy.org/blog/psychpedia/feral-children.

(3) Mailonline, Z. R. “Patients Left Blind Through Devastating Brain Injuries Are Able to See Again After Undergoing Routine Eye Surgery.” Daily Mail Online, Associated Newspapers, 12 Dec. 2016, www.dailymail. co.uk/health/article-4025022/Patients-left-blind-devastating-brain-injuries-undergoing-routine-eye-surgery. html.

(8) “Genie Wiley - TLC Documentary (2003).” YouTube, YouTube, 18 Jan. 2013, www.youtube.com/watch?v=VjZolHCrC8E. (9) “The Critical Period for Language Acquisition and Feral Children.” PennState, sites.psu.edu/psych256sp16/2016/04/21/ the-critical-period-for-language-acquisition-and-feral-children/.

(4) Cooper, Dr. J. “What Is Strabismus?” Optometrists Network, 2000, www.strabismus.org/vision_therapy_ for_strabismus.html.

(5) Hooks, B. M., and C. Chen. “Critical Periods in the Visual System: Changing Views for a Model of Experience-Dependent Plasticity.” ScienceDirect, Elsevier B.V., 25 Oct. 2007, www.sciencedirect.com/science/article/pii/

(10) Schmidt, S., and Bever, L. “How A Malnourished Teen Escaped A House Full of Chains and Freed Her 12 Siblings.” The Washington Post, WP Company, 16 Jan. 2018, www.washingtonpost.com/news/morning-mix/wp/2018/01/15/police-rescue-13-siblings-from-california-house-parents-charged-withtorture/?utm_term=.4f2614139e6e.

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