Yale Scientific Magazine Issue 85.3 April 2012 by Yale Scientific Magazine

everyday

Q&a

Q&A How Does Sunscreen Protect You? Sunscreen is a ubiquitous part of our culture, but how does it actually work? BY SELIN ISGUVEN

Sunscreen is comprised of particles that physically bounce radiation off the skin and react with UV rays. Courtesy of Korean Beacon

Q&A

Will a Magnetic Pole Shift Mean the End of the World?

Why a sudden reversal of your compass to point South is part of a natural phenomenon. BY JOSEPHINE SMIT -

- compass point South. Courtesy of lifeslittlemysteries.com

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contents April 2012 / Vol. 85 / Issue No. 3

NEWS

ON THE COVER

4 Letter from the Editor 6 Amasia: The Next Supercontinent 6 Supercomputing 7 Intelligent Buildings 7 "Kracking" the KRAS Code 8 Making Your Own Luck 9

ible to Few

10 Cryogenic IR Spectroscopy 11 Elegant and Simple: Understanding the

decision-making.

Interaction Between MDA5 and Viral RNA

FEATURES 2 Q&A 26 Pharmacology

Study Drugs and Neural Enhancers

27 Biochemistry

The Marijuana Receptors

28 Health 30 Medicine

Limiting Embryo Implantation

32 Bioethics Selling Sex... Cells 33 Biology Let Them Eat Cake: More to Obesity than Just the Extra Calories

Education, Part II 34 Science Sizing Up Science at Yale

Book Review The Aha! Moment: A Scientist's Take on Creativity

36 Darren Zhu, B.S. '13 37 Dr. Edward Cheung 38

Neurology Left Brain, Right Brain: An Outdated Argument

Machine Morality: Computing Right and Wrong Yale researcher Wendell Wallach considers the ethical, technical,

Using Placebos in Research: Ethical or Not?

The use of placebos in clinical research trials has been a hot-button issue in bioethics for decades. Bioethicist and Yale Professor Dr. Robert Levine believes that placebo in research is ethical, but only under the right circumstances.

The Healing Art of Meditation

Meditation has been believed for thousands of years to have healing powers. Now we are beginning to understand how meditation affects the brain. Dr. Judson Brewer of the Yale Medical School has shown meditation decreases activity of the parts of the mind associated with self-referential processing and mind-wandering.

Wolves and Wolfpacks: The Chase is On

One of the Many Quirks of Quantum: Perpetual Motion and Never-Ending Currents Yale Professors Jack Harris and Leonid Glazman put to rest quandaries surrounding the existence and nature of non-dissipating quantum currents. zero-point motion, these tiny currents are on the vanguard of our knowledge of perpetual motion.

Science and Religion: Reality's Toolkit April 2012 |

THEME

Controversies Ethics

13th Century:

in science

Compiled by Katie Leiby and Terin Patel-Wilson

1859:

1930:

1945:

1975

Science.

1996:

2006

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M A G A Z I N E Established 1894 April 2012

Volume 85 No. 3

Editor-in-Chief Publisher

William Zhang Elizabeth Asai

Managing Editors

Jonathan Hwang Robyn Shaffer Nancy Huynh Shirlee Wohl Mansur Ghani Renee Wu Ike Lee Jessica Hahne

Articles Editors News Editor Features Editor Copy Editors Production Manager Layout Editors

Li Boynton Somin Lee Jessica Schmerler Jeremy Puthumana Jonathan Liang Chukwuma Onyebeke

Arts Editor Online Editor Multimedia Editor Advertising Manager Distribution Manager Subscriptions Manager

Stella Cao Naaman Mehta Karthikeyan Ardhanareeswaran

Outreach Chair Special Events Coordinator Staff Kara Brower Matthew Chalkley Sunny Chung Andrew Goldstein Spencer Katz Sunny Kumar Katie Leiby Contributors Kevin Bohem Arash Fereydooni Walter Hsiang Selin Isguvin Sophie Janaski Bridget Kiely Achyut Patil

Lara Boyle Mary Labowsky Kaitlin McLean Jonathan Setiabrata Dennis Wang Jonathan Greco John Urwin Dennis Wang Katherine Zhou

Controversies & ethiCs in sCienCe As a kid, science always fascinated me for holding the explanations to the seemingly inexplicable, for providing the “why” behind life and the natural world. And while science certainly does convoluted than direct, with numerous contentious theories, competing interpretations, and widespread uncertainties, all nestled within each other like Russian dolls. Our established dogma in any Inevitably, closer inspection of any subject will reveal the cracks, but it can be staggering to hear

it frequently becomes infused with ethical concerns. Compounding this contention, these issues ‘tomorrow’s rear-view mirror’ and the fundamental principles of such endeavors. While it is easy to become caught up in the inherently loaded and innately interesting arguments, what is important to recognize is what scientists do agree on: the fact that the topic at hand is worth their investment and dedication to pursue, that they feel so compelled to search for the not necessarily prevent progress but rather can create it, spurring research and galvanizing new With this in mind, we delve into our theme of controversy and ethics in science, viewing the Geophysics doctoral student Ross Mitchell has recently proposed in Nature a new high resolution model of supercontinent formation, called orthoversion, as just one of the many paths of invescontinental drift. The concepts of disease have also been contentious and consequently evolving Statistical Manual of Mental Disorders, Yale Child Study Center Director Fred Volkmar and his

a leading researcher at Yale’s Interdisciplinary Center for Bioethics,

Josephine Smit Nicole Tsai Selen Uman Andrea White Joyce Xi Jason Young Zoe Kitchel

Advisory Board Sean Barrett, Chair Physics Priyamvada Natarajan Astronomy Kurt Zilm Chemistry Fred Volkmar Child Study Center Stanley Eisenstat Computer Science James Duncan Diagnostic Radiology Melinda Smith Ecology & Evolutionary Biology Peter Kindlmann Electrical Engineering Werner Wolf Emeritus John Wettlaufer Geology & Geophysics William Summers History of Science & History of Medicine Jeremiah Quinlan Undergraduate Admissions Carl Seefried Yale Science & Engineering Association The

FROM THE EDITOR

(YSM) is published four times a year by

We reserve the right to edit any submissions, solicited or unsolicited, for publication. This magazine is published by Yale College students, and Yale University is not responsible for its contents. opinions of YSM. We retain the right to reprint contributions, both text and graphics, in future issues as well as a non-exclusive right to reproduce these in electronic form. The YSM welcomes comments and feedback. Letters to the editor should be under 200 words and should include the author’s name and contact information. We reserve the right to edit letters before publication. Please send questions and comments to ysm@yale.edu.

machines that are capable of moral decision-making, which is especially relevant as Yale Associate Professor of Computer Science Brian Scassellati is now leading a federally funded, $10 million multi-university initiate to build a breed of “socially assertive” robots for assisting young children. Despite the nature of these contentious arguments, they have produced tremendous leaps in the will provide a glimpse of the controversy and ethics in modern science, along with a certain perspective to appreciate the relentless search for advancement and truth that will

William Zhang Editor-in-Chief

About the Art The cover, designed by Arts Editor Jeremy Puthumana and Editor-in-Chief William Zhang, depicts a dominant, overpowrepresenting the struggle between man, responsible robotics, and the the potential consequences we need to evaluate. Wendell Wallach, a leading researcher at Yale’s Interdisciplinary Center for Bioethics, investigates the ethical challenges of future technologies and how to implement moral decisions, particularly in robots and computers. Production Manager Li Boynton designed the headers on pages 16, 18, and 24.

GEOLOGY

AmAsiA: The NexT supercoNTiNeNT BY ANDREA WHITE

Researchers predict the formation of a new supercontinent that will form as America and Asia fuse. Courtesy of Nature

Nature

SUBJE -

COMPUTER SCIENCE

supercompuTiNg reveAls uNiverse secreTs BY NICOLE TSAI

Artistâ&#x20AC;&#x2122;s depiction of an expanding Universe.

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ENGINEERING

New grANT for iNTelligeNT BuildiNgs projecT

of building electricity

- consumption based on

ECT

building usage patterns

- Courtesy of Professor - Savvides

MEDICINE

“KrAcKiNg” The KrAs code -

Pictures of human endometrial tissue with the KRAS variant - (right) and the wild-type (left). Courtesy of ProfessorTaylor

April 2012 |

MATH

Making Your own Luck BY ACHYUT PATIL -

causal

does

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PSYCHOLOGY

new Definition of autisM: froM fLexibLe to few

The Wall Street Journal

Journal of the American Academy of Child and Adolescent Psychiatry. April 2012 |

CHEMISTRY

CryogeniC ir SpeCtroSCopy BY MATTHEW J. CHALKLEY

Science

2 2 2

2 2

Sample difference spectrum that shows how the 13C shifts a single oscillator. Courtesy of Professor Johnson

13 15

An image highlighting a single hydrogen bond and how its surroundings can be determined. Courtesy of Professor Johnson 10

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BIOLOGY

elegant and Simple: UnderStanding the interaCtion between mda5 and Viral rna In the proposed model of MDA5 signaling, MDA5 binds cooperatively to and forms filaments along dsRNA. If they reach a certain length, MDA5 filaments can interact with MAVS (red), which trigger the interferon response through the formation of signaling complexes. Courtesy of Dr. Berke

Negative stain electron microscopy shows MDA5 filament formation when MDA5 is mixed with dsRNA. The longest observed filament lengths were comparable to the length of the largest 6.4 kb genomic segment. Courtesy of Dr. Berke

This model, developed through the use of crystal structures and small angle X-ray scattering data, shows the structure of MDA5 when it is not bound to dsRNA. Courtesy of Dr. Berke April 2012 |

Using Placebos in Research Ethical or No t ? BY BRIDGET KIELY

n 1996, George Doeschner, a 53-yearold electrician with Parkinson’s disease,

suggestion to treat their patients. Despite their widespread use in the 19th century as a medical therapy, it wasn’t until

enroll in a clinical trial. Researchers there were testing an experimental treatment

important tool in clinical research. In his landmark 1955 paper The Powerful Placebo, procedure, his surgeon put him under anesand then closed him up again — without This was no surgical error. Doeschner had

with these issues. From Therapy to Research

when testing new therapies, they needed th

century. Physicians

“sham” surgery in which their skulls were

pill contained nothing more than sugar.

into the operation, Doeschner knew that

gold standard in clinical research. In these Doeschner’s surgery took place more than research are still pertinent today. When is it

th century, In some situations, the use of placebos

undivided loyalty to the interests of their patients. Courtesy of DrexelMed.edu 12

tricky part is determining when it is accept-

BIOETHICS

researcher were conducting a clinical trial on “Undivided Loyalty”

such a situation could cause death or permanent harm to participants, the researcher the known treatment. -

that it depends on the situation. such as heart attack, stroke, and kidney

Dr. Levine believes that placebo use in research on conditions like hypertension is acceptable if certain precautions are taken. Courtesy of TheSurvivorsClub.org

serious complications. Second, all trial parresearch in society, and the moral duties that Use of placebo control groups has been the gold standard of clinical research since the 1960s. Courtesy of Tulane.edu

About the Author Bridget Kiely

AcKnowledgements there’s no medication out there that anyone thinks is any good, then it is considered ethi-

Further reAding cumstances under which it is clearly unac-

The Healing Art

or thousands of years, Buddhist monks have used meditation to obtain a transcendental experience on the path to enlightenment. More recently, physicians have clinically employed meditation to successfully help treat disorders like depression, anxiety, addictions, and chronic pain. However, until recently, the effects of meditation on the brain were largely unknown. Dr. Judson Brewer of functional changes in the brains of experienced meditators in an exciting new fMRI brain imag-

of good will toward oneself and others that is supported by silently repeating phrases such as â&#x20AC;&#x153;may X be happyâ&#x20AC;?; and choiceless awareness, where the subject can focus on whatever object comes to them. Brewer and his team found two notable trends in the results of the study. First, experienced meditators showed deactivation of the part of the brain known as the default mode network (DMN), a region involved in selfreferential processing, including daydreaming. All three forms of meditation showed similar results. This discovery is interesting because one of the goals of meditation is to remain focused, and deactivation of the DMN seems to show that meditation is functionally doing just that in the brain. As meditators self-reported

the DMN is related to a reduction in mindwandering. Second, the brains of experienced meditators showed different connectivity patterns, i.e. different networks of the brains talking to each other, which had not been seen before in this context. They found that experienced meditators showed co-activation of the posterior cingulate cortex (PCC), dorsal anterior cingulate cortex (dACC), and dorsolateral prefrontal cortex (dlPFC) at baseline and during meditation. These altered connectivity patterns were consistent both during rest and during meditation. The PCC is an important part of the default mode network, and the dACC and dlPFC are both crucial regions for cognitive control. Exactly how these connectivity changes translate into functional changes is currently unclear, but the fact that the changes were seen

meditation on brain function and connectivity. Brewer started meditating during medical school to help cope with stress. He found it very helpful, and about 10 years later, began studying it clinically using functional magnetic resonance imaging (fMRI). fMRI is a safe, support the hypothesis that deactivation of non-invasive technique that measures oxygen levels in the brain, correlating oxygen concentration to brain activity; more active regions require more oxygen. In his study, Brewer performed fMRI brain scans on experienced meditators and controls (inexperienced meditators) both at rest and while using mindfulness meditation, a meditation that encourages acute awareness of physical or spiritual realities. The subjects in the study used three The study shows that experienced meditators demonstrate coactivation of the medial prefrontal types of mindfulness meditation techniques: concentration, functional connectivity with the mPFC region and left posterior insula is shown in meditators vs in which the subject focuses on controls: (A) at baseline and (B) during meditation. Courtesy of Dr. Brewer (Fig. 3 of Brewer et breathing; loving-kindness, where al. (2011) Meditation experience is associated with differences in default mode network activity the subject focuses on a feeling and connectivity. PNAS 108:20254-20259) 14

| April 2012

PSYCHIATRY during both meditation and resting periods suggests that with practice, meditation may transform the normal, resting functioning of the brain into one that more closely resembles a meditative state. In other words, the default state could shift from that of mind-wandering to one of being centered in the present. Why a decrease in activity in the part of the brain involved in self-referential processing and ately intuitive. Most people spend a great deal of time allowing their minds to wander since it usually seems more enjoyable than writing papers, crunching numbers, or listening during class. However, a 2010 study conducted by researchers from Harvard published in Science, entitled “A Wandering Mind is an Unhappy Mind,” found that subjects daydreamed during nearly 50 percent of their waking hours, and

The fMRI machine uses magnetic resonance to determine the amount of oxygen usage in the brain. Higher oxygen levels correlate to higher activity of that area of the brain. Courtesy of Wikipedia that overall, doing so made them unhappy. Not surprisingly, when their minds wandered toward negative things, they were less happy, but when daydreaming about positive things, they were actually no happier than when thinking about their current task. Given that on average, “a wandering mind is an unhappy mind,” it is easy daydreaming on emotional health. Meditation, however, does not only have dence suggests that mindfulness training can help anxiety, chronic pain, addictions, and other disorders, but exactly how meditation affects these conditions is still unknown. As Brewer asserts, what is exciting about his research is that it “might bring in some of the neurobiological

evidence as to what’s actually happening, and how the brain might be changing with practice.” He also points out that his study is a preliminary cross-sectional study that only examines one time point, but the evidence is quite persuasive. This research supports the role that meditation can play in the clinic. According to Brewer, “It [meditation] could certainly be used to help people work through frustration and anxiety so that they don’t move into a clinical depression or clinical anxiety disorder, or start using drugs. But at the same time, it can be used when people already have these disorders.” In a previous study, Brewer taught mindfulness training to people who wanted to quit smoking to six times before. Meditation was able to help these individuals quit smoking when all other methods failed. His recent discovery of functional changes in the brains of experienced meditators is a starting point down a longer road of determining the biological changes associated with meditation; Brewer says: My hope is that we can start to marry some of these ancient techniques that have been around for 2,500 years with some of the modern technology that might help actually synergize with these such that we actually help people. We’re excited that this could lead to the brain, but bringing what we learn from these neurobiological studies to actually augment the clinical practice. The future for clinical meditation seems bright. Indeed, it is remarkable to observe that certain cultures have practiced for thousands of years.

The art of meditation has been practiced for thousands of years. Buddhist monks in particular have long used this technique to obtain a transcendental experience on the path to achieving enlightenment. Courtesy of Fotopedia If you are interested in getting involved with meditation, there are many easy ways to get started. is a book on mindfulness training that can be downloaded for free online, and a free app called “Get Some Headspace” gives ten days of free guided meditations. Joining a local meditation group is also a common way to begin. Brewer leads a drop-in meditation group at Yale’s Dwight Hall Chapel on Mondays and Thursdays at 8:00 that is open to all who are interested. Beginners are given instruction and guided meditation, and the session ends with a discussion about meditative practices. Brewer urges, “Don’t get discouraged when trying to meditate is distressing. Stick with it. Find a good group and a good teacher.” Research shows that, with practice, meditation can be helpful in reaching a happier, healthier state of mind.

About the Author

Kaitlin Mclean is a junior in Jonathan Edwards College majoring in Molecular, Cellular and Developmental Biology with a concentration in Neurobiology. She works in Professor Crews’ lab studying the molecular mechanisms of limb regeneration in axolotls.

acKnowledgeMents The author would like to thank Dr. Judson Brewer for his time, enthusiasm in his research, and contributions to the article.

Further reading Brewer, JA, Worhunsky, PD et al. “Meditation Experience is Associated with Differences in Default Mode Network Activity and Connectivity.” 108 (2011) 20254-9.

April 2012 |

he world of quantum mechanics is, to the average person, a world of

that emerge from the equations of quantum

produced that would never dissipate!

intriguing facets of quantum mechanics â&#x20AC;&#x201D; to that of persistent current: a natural electric ics, particles are treated as standing waves and thus have wave properties, including

treating electrons as point particles with a Ă&#x2014;

Quantum in a Nutshell (The ABCs of E=hv) The core tenet of quantum mechanics is

mathematical formulas whose solutions are

Standing waves on a string come in discrete energy levels (n = 1,2,3,4â&#x20AC;Ś) in the same way that standing waves in three dimensions are only allowed certain energy levels. The top string has energy n=1 and contains one node at each end. The next allowed energy level is n = 2, with an additional node in the center. As can be seen, quantization emerges naturally from the boundary conditions of standing waves. Courtesy of UCLA From e and I: Orienting zero-point motion

conclusions that emerge from the equations

the air, electrons too fall down their potential

PHYSICS

Diagram of the cantilever instrument used to measure the magnitude of the persistent currents. Courtesy of Professor Harris

strength and character of the currents pro perpendicular to the face of this molecule will orient the charge and cause an internal the electrons will circulate around the entire ring, not just around a molecule, causing a minum rings on micromechanical cantilevers

ture increases, the amperage of the current dwindles, resulting in a minuscule current at

electrons will continue to circulate and form few micrometers in diameter, comprising mil

and, again, after the induced current fades of magnitude greater than what was previ

About the Author Putting Theory to Rest

John Urwin C. elegans

Acknowledgements

ters, opens the circuit and redirects the cur Even though the persistent currents are small,

FurtHer reading -

FEATURE

PHARMACOLOGY

Study drugS and neural enhancerS Science and controverSy

Imagine a world in which you could increase your IQ by taking a pill. With the help of neuroenhancing drugs, such a world may already exist on college campuses across the country. According to a 2005 study published in the journal Addiction, seven percent of college students have admitted to using some kind of neuroenhancing drug for nonmedical uses. Although taking drugs without a prescription is illegal, not all scientists agree that consuming neuroenhancing drugs may be a bad thing. Are drugs like Ritalin and Adderall a glimpse into a smarter future, or are we toying with health risks we do not yet fully understand? The two favorite neuroenhancing drugs used on college campuses are methylphenidate and amphetamine salts— or, as we more commonly refer to them, Ritalin and Adderall. These drugs are typically prescribed to assist children and adults with attention deficit hyperactivity disorder (ADHD).

dangers of Adderall and Ritalin, even ranking them as less dangerous than beer and cigarettes. Despite the potential health risks of such drugs, not all scientists are on the same side of the argument. A recently published article in Nature

should be able to use drugs to improve brain function in the same way that they use food, sleep, and exercise to improve brain function, these scientists and ethicists argue that as long as such drugs are proven to be safe, they should be embraced and not stigmatized. They also reject the notion that humans should not use mind-enhancing drugs because they are “unnatural,” stating that much of our lives today are already unnatural. Furthermore, the article urges scientists to start researching the benefits and risks of using these drugs on healthy adults and the government to alter laws surrounding drugs so that those attempting these drugs in adults to enhance their cogniwithout ADHD, Hedy tive abilities will not be Kober, Assistant Propunished. fessor of Psychology Dr. Nora Volkow, and Psychiatry at Yale the director of the University states, “we National Institute on Drug Abuse, has called of reason to believe the article “irresponthat these drugs can in Ritalins block dopamine reuptake in the same way that cocaine does. Courtesy sible” and states that she fact enhance the per- of canadian-seeker.com strongly disagrees with formance of healthy adults as measured by, for example, reaction time, its authors. She adds that Adderall and Ritalin are stimulants that can lead focus, and some forms of memory.” Kober explains that by blocking to severe addiction and psychosis. Furthermore, Volkow argues, because or otherwise altering the function of the transporters in the synapse there have been no long-term studies on the effects of these drugs on that reuptake the neurotransmitter monoamines, Ritalin and Adderall young brains, these drugs could result in long-term, adverse side effects. increase monoamines levels, especially dopamine, in synapses. The On the other hand, Dr. Kober agrees with many of the claims made resulting high levels of dopamine are able to enhance signals between in the Nature article. “In a world where healthy people could get these the hippocampus, which is involved in memory, and the prefrontal drugs through a prescription,” she states, “this kind of drug use could cortex, which is involved in decision-making. These enhanced signals be very helpful and practical.” She lists some studies that show that are thought to be responsible for the increase in cognitive abilities and regular smokers perform better cognitively when they are given nicoworking memory upon taking these drugs. tine. “We all intake things like food, sugar, and caffeine in order to alter Although she acknowledges the value of neuroenhancing drugs, our current state and enhance performance,” Kober argues. As long Kober cautions students about taking drugs that are not prescribed to as neuroenhancing drugs are safe and legal, she contends that people them. “There is always a concern of drug interaction when you don’t should be allowed to use them. know what you are taking and you haven’t consulted a doctor about issues As Adderall and Ritalin consumption among college students remains like dose and other existing medical conditions,” she warns. Furthermore, she explains that both Adderall and Ritalin are schedule II drugs, mean- roenhancing drugs will continue. The future implications of such a ing that they have an “abuse potential” and can lead to dependence and trend are much bigger than simply earning an “A” on an exam, though: withdrawal. Though this may seem like an obvious caveat, many students although many health risks need to be evaluated, the use of cognitive nonetheless fail to understand these risks. A survey conducted at the enhancing drugs may not only improve the performance of college University of Kentucky shows that many students underestimate the students but also increase the cognitive abilities of humanity as a whole. 26

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BIOCHEMISTRY

FEATURE

the Marijuana receptorS

a new Medical target?

Banned by the U.S. government and legalized by other nations, praised by some college students and disdained by others, marijuana is an issue of contention not only in policy writing but also in the medical sphere. The endocannabinoid system — which regulates the psychoactive effects of marijuana — is emerging as a new medical target in pain research and many other areas, such as weight loss and neurological disorders. However, the stigma associated with cannabis and cannabinoids leave scientists and doctors in a controversial conundrum. “young” discovery in the world of signaling systems (the term “endocannabinoid” was coined in the mid-1990s), it is surprisingly heavily involved with a number of our bodily functions and pathological conditions. This elaborate network of receptors and proteins — which includes endocannabinoids, enzymes, and

raised ethical controversies; when we try to manipulate a system as ing, we can end up with a broad spectrum of unintended effects. “It is virtually impossible to selectively interfere with either a brain region or a peripheral organ such as the liver, without having any other impact on other tissues,” Horvath adds. Other pharmaceutical companies have tried to develop powerful painkillers that imitate how the active ingredient in marijuana, deltaendocannabinoid system. The British company GW Pharmaceuticals is one of these companies currently seeking FDA approval for their marijuana mouth spray, Sativex. GW Pharmaceuticals is attempting to quell concerns of recreational drug abuse by utilizing only two cannabinoid compounds that could counterbalance each other:

believed to suppress the “high” in our immune function, autofeeling that comes as a side effect nomic nerve function, memory, stress response, and appetite. tises that Sativex, as a mouth spray, Research even demonstrates a takes at least an hour to start proclear relationship between altered ducing an effect — a time period endocannabinoid signaling with too long to be easily abused by cancer, cardiovascular disorders, drug users. eating disorders, and psychiatric Although the FDA has set strict and neurological disorders. guidelines regarding cannabinoid pharmaceutical drugs, there is erful role in regulating cravings, evidence that a policy shift may mood, pain, and memory, drug soon allow more of these drugs designers have endeavored to to appear on the market. In the develop drugs that can improve one’s physical and mental health The ECS is responsible for appetite and award-seeking behavior. drugs based on synthetic candespite much controversy. While Courtesy of BBC Science Features nabinoids, were approved for some researchers have been sucalleviating the nausea and vomitcessful, others point out gaps in our knowledge and understanding ing for patients undergoing chemotherapy and for stimulating the appetite of patients with AIDS. Further trials for these drugs have began selling a new weight-loss drug, Rimonabant, that worked by concentrated on movement disorders such as Parkinson’s syndrome, chronic pain, dystonia, and multiple sclerosis. Despite claims that months, however, the company had received more than 900 reports these drugs are based on synthetic compounds and have low risk of side effects, such as depression and nausea, and the drug was of physical or mental dependence, concerns still exist over whether then pulled from the market. Studies later linked the existence of such cannabinoid-based drugs could or would still be abused for recreational use. “It’s against the propagation of life in the long run to interfere with the central components of appetite,” asserts Dr. Tamas Horvath, groundbreaking medical treatments, the extensive and highly inteworks as a Professor of Neurobiology and Obstetrics, Gynecology, tively affecting the other parts of body. The quest and urge to better understand the endocannabinoid system needs to be tackled before April 2012 |

FEATURE

HEALTH

What am I EatIng? thE InfIltratIon of gEnEtIcally modIfIEd foods By WaltEr hsIang

The majority of common vegetables and fruits are now genetically enhanced to improve traits such as increased shelf life and increased crop yield. Courtesy of Dr. Fans

A common genetic engineering technique called microinjection. This technique does not rely on biological vectors such as viruses to insert DNA into a new genome; it simply injects genetic material containing the new gene into the recipient cell. Courtesy of GenerationGreen 28

| April 2012

HEALTH

lie not in food production, but in the infrastructure for and distribution of food. Courtesy of Cross Catholic Field Blog April 2012 |

FEATURE

MEDICINE

The More The Merrier: LiMiTing The nuMber of eMbryo iMpLanTaTions BY JESSICA SCHMERLER QuĂŠbec

multiple times.

Some clinics choose to culture embryos slightly longer, to the blastocyst stage, before reintroducing them in order to increase likelihood of implantation. Courtesy of nfcares.com 30

| April 2012

MEDICINE

FEATURE

Often cited as the downside of multiple embryo transfers, Nadya Suleman had twelve embryos transferred and gave birth to octuplets in 2009. Courtesy of news.softpedia.com

Multiple embryo transfers during fertilization can often lead to the undesirable consequence of multiple gestations, as shown in this ultrasound of triplets. Courtesy of Raphael Gonzalez & Richard Woods

April 2012 |

FEATURE

BIOETHICS

Selling Sex... CellS

navigating the ethiCS of the Sex Cell Market BY MEREDITH REDICK For several decades, assisted reproduction technology has helped infertile couples realize their dreams of having children. However, this process requires gamete donors — men and women willing to give up their own sex cells. Thus, while the emerging market for sex cells has ushered in hope for many couples, this promise comes at a price.. While sperm donation can hardly be called invasive, egg donation, on the other hand, poses many risks that are not all fully understood. To donate, a woman must take hormone injections for several weeks. Typically, a gonadotropin-releasing hormone agonist is injected to prevent normal pituitary stimulation of egg development. After one to two weeks, follicle-stimulating hormones are injected to promote

Almeling explains. “We don’t even really have short-term studies. I think when a woman goes in and is asked to give informed consent, it can’t be true informed consent. They need to be advised that we don’t have good data.”

injection of human chorionic gonadotropin stimulates egg release. Retrieval requires surgical insertion of an ultrasound-guided needle through the vaginal wall into the ovary. For some women, maturation of multiple eggs results in severe Three days after conception, this embryo consists of 8 cells. Courtesy of Wikipedia The increased risk associated with egg donation means that women are typically paid much more to donate sex cells than men. Men are typically paid about $100 per sperm sample, whereas women can be paid more than $5,000 for a single cycle. In other words, egg donaexploitation of the sex cell market. In response, the American Society of Reproductive Medicine has issued guidelines recommending against remuneration exceeding $10,000. Furthermore, Almeling writes that egg donation agencies tend to use altruistic and “gift of life” language to persuade women to donate. She suggests that this advertising method might be partially due to the need to screen out women who are interested only in making money from donation, since women in A basic overview of how eggs are transferred in assisted reproductive technologies. Courtesy of the Fertility Institute of New Jersey & New York abdominal cramping. Women preparing to donate might have as many as 40 follicles ripening in their ovaries as a result of the hormone treatments. For some, the problems exceed discomfort. In her book Sex Cells: The Medical Market for Eggs and Sperm, Dr. Rene Almeling, Assistant Professor of Sociology,, reports estimates from the American Society for Reproductive Medicine that in one to two percent of egg donors, too many eggs mature simultaneously and produce serious complications. In women with severe ovarian hyperstimulation abdomen, causing bloating and, in rare cases, kidney failure or death. In addition to the risk of OHSS, egg donation may pose long-term risks. Unfortunately, the seriousness of these risks remains fairly nebulous. Several cases of cancer have been linked to hormone treatments, but thorough research has not been conducted. “We do not have good long-term follow-up clinical studies about what happens to young women who are repeatedly exposed to fertility medications,” 32

| April 2012

The effects of such ethical concerns about egg cell donation are present not only in fertility clinics but also in research laboratories. Researchers have established that immature egg cells are excellent candidates for stem cell research. Instead of using embryonic stem cells, scientists could grow their stem cells in the lab from somatic cell DNA and egg cells. This practice would be a win-win for both the public and scientists, eliminating the current controversy concerning the destruction of human embryos. However, the federal government does not currently compensate women who donate eggs to stem cell research, which has resulted in an egg cell shortage in laboratories and a continuation of the stem cell debate. For the time being, standing ethical and biological issues shroud well-regulated market could provide. Although the procedure of obtaining egg cells has been standardized and proven successful for many couples, nuanced questions of how to compensate donors and to prevent incest between children from a single sperm donor have yet to be resolved. But for now, egg cells are a coveted yet controversial commodity for infertile couples.

BIOLOGY

FEATURE

let theM eat Cake

More to obeSity than JuSt the extra CalorieS BY KATHERINE LEIBY With a quick glance around, we can tell that the obesity epidemic is becoming more and more prevalent. And the greater our body weights become, the more we see the whole host of diseases that come along with obesity as well, including diabetes, heart disease, and even some types of cancer. We like to think that preventing obesity is a simple matter of personal responsibility, and that if we only used our willpower, we could right the imbalance between our caloric intake and expenditure. But it is becoming increasingly clear that solving the obesity problem will require more than the treadmill. There are at least 32 gene variants that have been implicated as links to obesity, including one that decreases our propensity to choose healthy, low-fat foods. At various times, hormones in our gut, like glucagon-like peptide 1 and oxyntomodulin, are sending satiety signals to our brain, reducing our food intake, while others hormones, like ghrelin, are stimulating our appetites. The peptide hormone leptin, which is secreted by fat tissue and suppresses hunger, was once even a prime candidate for drug therapies — until we realized that blood concentrations of leptin actually increase with body fat and that most obese individuals have developed a resistance to the hormone.

environment, efforts at self-control may not be enough. tious origins, an idea encompassed in the term “infectobesity.” Already, six different pathogens have been indicted as causing obesity in animals, two of which are also associated with human obesity. Many more obese individuals than lean individuals harbor antibodies in their blood to the human adenovirus, or Ad-36, a pathogen responsible for causing respiratory tract infections, suggesting a link between human obesity and Ad-36.

The obesity epidemic is on the rise worldwide. Courtesy of

The Nutrition Post An even more startling discovery supporting the idea of infectobesity was made in a recent study led by Dr. Jorge Henao-Mejia, Dr. Eran Elinav, and Mrs. Chengcheng Jin in the laboratory of Dr. Richard Flavell, a Sterling Professor of Immunobiology at the Yale School of Medicine and a Howard Hughes Medical Institute Investigator. Their study suggests yet another way in which obesity could be infectious: through gut microbiota, bacteria that live in our intestines. These bacteria populations

Researchers used mice like these in order to better understand the role of the peptide hormone leptin. Courtesy of

Proceedings of the National Academy of Sciences Ashley Gearhardt, a clinical psychology doctoral student at Yale, also discovered that some people show both the neurological and behavioral signs of substance dependence in response to certain craveable types of food, such as ice cream, french fries, and candy, much like a smoker responds to cigarettes. What is intriguing, Gearhardt says, is that not all obese individuals exhibit “food addiction” and that not all lean individuals are free from these signs of dependence. But those who are addicted to food demonstrate the same neural response patterns to food cues as would be predicted for those with substance dependence. Food addiction brings into question the role of our food environment, in which highly processed foods are advertised through “guerrilla marketing,” particularly to children. We do not yet understand all of the potential consequences that these highly marketed, rewarding foods may have, though Gearhardt suggests that they offer “the potential of hijacking control for at-risk individuals.” When faced with such an intense food

— and therefore had altered gut bacteria populations — exhibited a higher incidence of fatty liver disease and obesity when fed a high-fat diet. The same severity of disease was reproduced in healthy mice merely by cohousing the two populations, suggesting that the altered gut bacteria condition was infectious. Elinav is quick to emphasize that this study does not suggest that gut microbiota cause obesity, but rather that it is the combination of diet, another contributing mechanism [to obesity],” he explains, “ [but] the dietary component is of no less importance.” Both the high-fat diet and the necessary driving factors for the development of liver disease and obesity. the more and more complex web of obesity, one in which we as humans are becoming increasingly trapped. Obesity is not a simple problem with a straightforward solution, and it does not look like we will be stumbling uting factors — genetics, hormones, addiction, viruses, gut microbiota — we know that there is much more to be blamed in this epidemic than just that extra slice of chocolate cake. April 2012 |

FEATURE

EDUCATION

Sizing Up Science at Yale part ii of Science edUcation at Yale BY DENNIS WANG from Yale College, was founded in 1854. Today, science is an integral part of the liberal arts education at Yale and is a required component of the distributional requirements. Science education at Yale has evolved, and quantitative measures of the present state of science at Yale are the subject of constant scrutiny. Quantifying the Experience According to a recent Yale Daily News article, 30 percent of freshmen at Yale start out in science, technology, engineering, or mathematics (STEM), but only 19.9 percent of seniors graduate with STEM degrees, compared to 28.5 percent of Harvard graduates and 36 percent of Stanford graduates. Retention in the sciences is low at Yale, which may be partly due to the strength of its Humanities and Social Science Departments. The conducted a survey which found that 56 percent of science majors had seriously considered non-science majors, and that 64 percent of science majors were pre-medical students. Matriculation in the sciences, however, is lower than at Harvard, Stanford, or MIT, and explains the lower percentage of science graduates at Yale. ence programs. As noted by William Segraves, Associate Dean for Science Education, science at Yale is “an enormous enterprise with many dimensions.” Its merits and shortcomings deserve to be assessed independently by the students and faculty that they most affect. Qualifying the Experience The asked 103 Yale science and non-science majors whether they agreed or disagreed with the following statements on a ten-point Likert scale, where “1” represented strong disagreement and “10” represented strong agreement. The results are arranged in the following table: Claim Science at Yale is stronger than social sciences or humanities at Yale. Science at Yale is stronger than science at Harvard or other comparable schools. Science at Yale has a strong reputation. Science at Yale has a strong program. Yale is doing enough to promote science education. The overall science experience at Yale is good.

Likert Scale 2.6 4.8 6.0 7.0 5.6 6.3

Additionally, survey respondents were asked what they considered to be the greatest strengths and weaknesses of science at Yale. Students believe that the sciences at Yale are stronger than their reputations imply, citing the low student-faculty ratio in advanced classes and peers with interests not limited to science. While science students at Yale represent a smaller minority of the population than at Harvard and Stanford, Michael McBride, Colgate Professor of Chemistry, notes that the focus 34

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Sterling Professor of Molecular Biophysics and Biochemistry Thomas Steitz won the 2009 Nobel Prize in Chemistry for solving the structure and function of the ribosome. Like many Yale professors, Steitz has undergraduates working in his laboratory. Courtesy of Yale University of professors on undergraduate STEM education distinguishes Yale from comparable institutions with larger programs. Other students note the abundance of research opportunities and funding through the Science, Technology and Research Scholars (STARS) program and the freshman Perspectives on Science and Engineering (PSE) program. Segraves, who organizes PSE, notes that “research is deeply embedded in the culture here.” However, science at Yale still has room for improvement. Science majors complain about the inconvenient location of Science Hill, ambiguity in grading, lack of course variety, poorly-taught introductory classes, and the lack of a full credit for labs. Science majors and nonmajors identify a rift between the sciences and other disciplines, though student opinions vary on science distributional requirements and courses for non-majors. One student, in naming the best and worst things about science at Yale, quipped “being at a liberal arts school.” Looking Ahead In 2000, President Richard Levin announced a $1 billion commitment to the sciences, expressing his hope that “our billion dollar investment means that the University’s image will change somewhat and that we’ll be President’s Council of Advisors on Science and Technology, called for the STEM Teaching Transformation Committee to improve the quality of science facilities and education. Dean Mary Miller indicated in the 2011 Yale College Curricular Review that “Yale should make a commitment to do more to prevent [attrition from STEM majors] and potentially even attract more of our students to science and engineering,” noting that “the deferral of improvements to science and engineering facilities with the economic downturn has squeezed teaching and learning opportunities.” ten, or 20 years as facilities, programs, and students continue to develop and evolve, but as Segraves says, “The only thing that’s certain is that it will be different!”

BOOK REVIEW

FEATURE

BY RENEE WU

Rating: who revolutionizes the industry with a brilliant idea that changes the world. Musicians compose in hopes of becoming as commonly known a name as Beethoven; authors look to Hemingway and Fitzgerald for inspiration for their own works. Regardless of whether we aspire to be the next Picasso or Armani, we all look to “the Greats” with slackjawed wonder, each of us longing to achieve the crown jewel of human thought: a creative idea. So where do these ideas come from? A retired chemist best known for his columns as the comical Daedalus in the New Scientist and Nature, David Jones describes his theory of creativity in his recent book Take on Creativity. Writing about his own creative journeys in science as well as offering dozens of other

discarded as too illogical by Observer-Reasoner, Jones writes that this is the “aha!” moment that we all crave RIG and “outwitting” our Censor, though most of his book elaborates on the former. According to Jones, there are two components in the RIG to being creative: (1) amassing a large pool of knowledge and experience through life experiences, reading articles, vigilant curiosity, and constant observation; and (2) encouraging the RIG to play with information and stimulating it to pass up ideas to the Observer-Reasoner. The book perfunctorily encourages us to always carry a paper and pencil to jot down ideas the RIG may send at any moment, to try our our RIG more challenges to play with, to keep a personal database of documents power of emotional feelings, sexual tension, and intuition. In the second half of the book, readers are treated to a long parade of the triumphs and experiments in Jones’ career that he attributes to this mode of creative thinking. Describing the thought processes that led to his accomplishments working with NASA, his study of

how we may change our ways of thinking to enhance our creative thoughts. Jones simplifies the human mental structure into three parts: the Observer-Reasoner in the conscious mind, the Censor in the subconscious mind, and the Random Ideas-Generator (RIG) David Jones describes how we can stimulate our creinspired to study because of his amazein the unconscious mind. We have ative muscles in his new book. Courtesy of Idaho Falls ment that he could ride a bicycle even different levels of access to each of Public Library when drunk), and dozens more, Jones the three levels, with full awareness hammers home the same message with his many examples: Creativity requires a cross-training kind of thinking and no controllable contact with the RIG. All of our thoughts, deci- in which novel ideas are based on pattern recognition and looking at sions, and ideas depend on the interaction of the three layers, but we things in fresh perspectives, not inspired guesswork. can change how strong each of the layers are to enhance our creativity. Despite the many original descriptions of the thought processes that Most of is spent describing the importance of the led to novel discoveries, itself does not provide any RIG, with Jones comparing it to “a pet animal … you can be fond extraordinarily novel perspectives on creativity. Although Jones writes of and pleased with what it gives you.” The RIG is described like a about his examples in a playful and light-hearted manner, the sheer vast, swirling pool of information that is collected and enhanced as number of examples he includes to emphasize his message feel somewhat you learn, read, and experience more. Like a “pet,” the RIG is always tiring by the end of the book. Additionally, at some points, the book active and plays with this information to combine or generalize into a seems to take the idea of the RIG too far, such as when Jones suggests package that is sent to our conscious minds, the Observer-Reasoner. that a woman’s unconscious mind selects eggs it believes are well-suited for the men in her life. through the Censor, which strictly tries to oppose whatever the RIG Nonetheless, of dangerous absurdities and mad possibilities [from] being tossed around” in the RIG, it can also impede creativity. In the case that an idea is able to break through the barrier of the Censor and is not

not become the next Steve Jobs or Picasso, Jones lets us enjoy a journey inside his creative mind in hopes that we may branch off onto our own innovative paths. April 2012 |

FEATURE

UNDERGRADUATE PROFILE

The Road Less TRaveLed: daRRen Zhu, B.s. ’13 BY ANDREW GOLDSTEIN Last year, Darren Zhu was in his sophomore year as a chemistry major; this year, the former member of the Yale Guild of Carilloneurs is marching to a different tune as he launches a biotech start-up company in Palo Alto, California. The 2,600 mile transition was facilitated by Zhu’s selection as one of the recipients of the 20 Under 20 Thiel Fellowship, sponsored by Peter Thiel, a prominent Silicon Valley venture capitalist who is perhaps best known Facebook. The son of a professor and an engineer, Zhu cultivated his interest in science and technology through science fairs, classes at the North Carolina School of Science and Math, and research experience during his senior year of high school at the University of North Carolina at Chapel Hill. At Yale, he dabbled in chemistry, mathematics, economics, computer science, and biology. However, he realized that his true interests lay at the intersection of science, technology, and business after helping start and run Yale’s team in the International Genetically Engineered Machines (iGEM) Competition. While working with this group of students to engineer E. coli to churn out a new anti-freeze protein, Zhu became immersed in array of applications in biotechnology. “Founding a biotech start-up became a dream of mine, but I didn’t Darren Zhu ’13, speaking at the 2009 Davidson Fellows Ceremony in Washingthink that it would be accessible until much later in ton, D.C. Courtesy of Darren Zhu my career,” he explains. best way to learn how to run a start-up is to jump right in there and Yet less than a year later, Zhu won a $100,000 Thiel Fellowship to try your hand at it: try to make something out of nothing.” pursue his interest in biotech. He started by teaming up with David Zhu recently received a new $100,000 grant from the Bill and Luan, another Yale student and Thiel Fellow, to start a biotech robotics Melinda Gates Foundation and plans to shift his focus for at least the next 12 to 18 months back towards synthetic biology to develop an in vivo of this project, working through logistics to acquire lab space to carry out his research and exploring a host of foundational synthetic biology techniques, such as next-generation DNA sequencing and synthesis that will support the research. His current project aims to supplant chemical- and microscopy-based diagnostic methods by developing an organism which is capable of detecting disease via the company, Dextro. Zhu and Luan sought to build a company that provided end-to-end automation of large-scale experimental procedures to various antigens. While Zhu is doubtlessly excited about his work in Silicon Valley, it This process involved making connections with various professionals, is also clear that a part of him misses Yale. His suite at Yale has been replaced by a house in Palo Alto with seven other start-up entreprelawyers, and various science/technical experts because, as Zhu explains, neurs, working on everything from electric motors to an e-commerce “you truly have to be a jack of all trades to found a start-up.” Recently, website and online educational tools. “Being away from Yale makes Zhu and Luan decided to abandon the project due to the fact that high you appreciate various things that you don’t really see while you are system infrastructure costs limited the product’s market to big biotech immersed in it,” he said. “It is rare to be surrounded by constant colcompanies and that many of those potential customers indicated that laboration, constant social engagement, and literally thousands of high caliber people with a diverse array of interests.” Would Zhu consider spending. However, Zhu is far from discouraged. In fact, he found returning to Yale eventually? “Of course,” he says, “but only if I run the process to be a fascinating learning experience, adding that “the out of money or ideas.”

“ ” You trulY have to be

a jack of all trades to found a start-up.

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ALUMNI PROFILE

FEATURE

an engineeR’s JouRney, BuiLding gadgeTs fRom aRuBa To nasa dr. edward cheung, school of engineering and applied science, ph.d. ’90 BY ZOE KITCHEL how everything on Earth worked. He recalls passing a day in his grandfather’s shop when a transistor radio fell to the ground and broke open so that its inner components were exposed. “I felt I was looking at magic,” he recounts. Since then, Cheung has transformed his boyhood curiosity into an extensive career that goes beyond planet Earth. Although Cheung grew up in Aruba, a small island in the Caribbean, he attended college at the Worcester Polytechnic Institute in Massachusetts. After graduating with a Bachelor’s of Science in Electrical Engineering, he continued his academic career in a microelectronics program at the Yale School of Engineering and Applied Science, where robotics took off. Under the guidance of Vladamir Lumelsky, Cheung worked on the development of robotic arms. “Before, a robot’s purpose was to be the object that puts [its components] all together,” he explains, “but Lumelsky had a new take.” Instead of a robot, this team focused on designing robots that could deal with unknown stimuli in novel environments. Cheung developed an array of sensors that essentially served as skin, covering the arm

about competition, Congress mandated NASA to develop the Flight Telerobotic Servicer, a space telerobot that would serve as a safe replacement of human crew in space. Due to Cheung’s experience “passing political winds” terminated it. Afterward, Cheung served as principle engineer of the Hubble Space Telescope Service Project, developing “several new components for the telescope, including the cryogenic cooler, the current main instrument (Wide Field Camera 3), and portions of the power control system.” Following the culmination of the Space Shuttle Program last summer, Cheung shifted to his current focus on the maintenance of geo-synchronous communication satellites. “These satellites sit in a very special orbit … because it takes these satellites 24 hours to travel to their original spots. It turns out that the Earth also rotates in this way,” he explains, “and as a result, they are stationary in the sky in respect to the Earth.” For each satellite to stay in its unique orbit, a small amount of rocket fuel is required that keeps the satellite in place for point it is released out of orbit and destroyed. To Cheung and his team, though, this practice seemed impractical: “Why can’t

Cheung worked to construct the cyrogenic cooler, the current main instrument on the Hubble Space Telescope Wide Field Camera 3. external satellite in order to board that allowed it to move Courtesy of Dr. Cheung prolong the life, saving NASA around. “Initially, I did not see it much of a research area,” Cheung explains, but he would soon $500 million per satellite?” he asked. NASA agreed. Now Cheung serves as the electrical lead of his team, designing, constructing, and change his mind. Because the intensity of graduate school was much greater than testing robots to repair and refuel these satellites. Although content with his current position, Cheung worries about he expected, Cheung made considerable efforts to engage himself outside of his research, particularly by bonding with undergraduates. the future of space exploration in the U.S. The end of the Space Shuttle Program leaves the United States dependent on other countries for space travel for at least another decade until the commencement of Yale, he greatly enjoyed his work as a teaching assistant, as well as his NASA’s Space Launch System. Nonetheless, he feels fortunate that involvement with the residential college system. One of his favorite memories was his Taekwondo classes in the tower of Payne Whitney electrical engineering but also sparks his creativity. “There are many Gymnasium. “In fact, in 1987, I was Connecticut state champion of ways to solve any problem,” he explains, “but the way in which you my weight and belt division,” he chuckles. After receiving his doctorate in Electrical Engineering in 1990, been recognized not only in the United States, but also in his home Cheung’s career took an exciting leap when he was recruited by the island of Aruba, the Netherlands, and throughout the world of robotKennedy Space Center in Florida and eventually offered a perma- ics and space exploration. In 2010, he was knighted by the Queen nent position by the National Aeronautics and Space Administration of the Netherlands and also received NASA’s Medal for Exceptional (NASA) at the Goddard Space Flight Center, where he has remained Engineering Achievement. Even though he has come a long way from for the duration of his career. Although he has worked at the Center for his roots, he has never lost his childhood delight for understanding over 20 years, his research focus has nonetheless changed throughout how things work. Today, he collects and refurbishes pinball machines for the joy of taking things apart and putting them back together, “just International Space Station were manufactured by Canada. Concerned like in my grandfather’s shop.” April 2012 |

FEATURE

NEUROLOGY

Left Brain, right Brain an Outdated argument BY KEVIN BOEHM many times have we characterized ourselves as either left-brained and logical people or right-brained and creative people? This popular myth, which conjures up an image of one side of our brains crackling with from the 1970s, and it seems to imply that humans strongly favor using although there are indeed differences between the hemispheres, they may not be as clear-cut as we once thought. Our personalities and abilities are not determined by favoring one hemisphere over the other — that much is certain. Many other functions, however, such as response to danger and language generation, are lateralized in the brain. Researchers hypothesize that these differences arose from early vertebrates. Originally, it seems that the right hemisphere began to respond more quickly to danger. In fact, when we are suddenly confronted by a dangerous stimulus, we will respond more quickly with our left hand, which is controlled by the right hemisphere. The left hemisphere, on the other hand, has developed to handle more common, routine tasks, such as feeding and hand control. Since this hemisphere controls the right hand, a strong right-handed preference has arisen in most of us, providing one explanation of why most people are right-hand dominant. Language is another process that is lateralized in the brain, though a study conducted by researchers at Ghent University has shown that the asymmetry differs when generating versus receiving language. When children were shown images and asked to tell a story about them, function was lateralized strongly in the left hemisphere for over 90 percent of participating children. However, when asked to listen to an emotional story, both hemispheres of the brain were activated to a similar degree as planning and articulation require more processing involving more regions on both sides of the brain. The stories the children listened to, unlike the pictures, were emotional, which may indicate that the observed involvement of the right hemisphere is linked to emotional regulation. Olivia Farr, a neuroscience Ph.D. candidate at the Yale School of Medicine, explains that this language lateralization is the source of many generalizations. “In some The right-handed bias has always been evident in humans, but scientists now ducted on hemispheric are discovering that it is not uniquely lateralization, splithuman. Monkeys and other primates brained patients without prefer to hold food with their right an intact corpus callohands. Courtesy of 123rf.com sum, or bridge between 38

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the two hemispheres, were examined,” says Farr. Because visual information from the right eye goes to the left hemisphere, when split-brained patients saw a word with their right eye, they could speak it but not draw it. When the patients saw a word with the left eye, they could draw but not speak it. These results contributed to the belief that hemispheres operate independently of each other The two hemispheres are separated for most tasks, which except for the relatively narrow corpus then developed into the callosum connecting them. This myth of being excluis the link between the processing sively left-brained or centers and the source of many of our right-brained. There was advanced abilities. Courtesy of Gray’s so little known about Anatomy, 1918 the brain that it was convenient to attribute poorly understood traits, such as personality or thinking habits, to a clear-cut difference in lateralization. However, “we now know that hemispheres are always communicating, and that Hemispheres sometimes do perform tasks nearly independently, but the integration of the two yields some of our most uniquely human characteristics. For example, when we make errors, our realization and ability to correct them is a result of the synergy of the two halves of our brain. In fact, patients with damage to the corpus callosum have corpora callosa, further suggesting that the two halves of the brain are both involved in processing the error. Even though some tasks usually occur preferentially in one half of the brain, it is possible for the part directly opposite to take control of the process. Such a process takes time, but after damage in the left inferior frontal gyrus (referred to as Broca’s area) — a region of the brain linked to speech production — researchers have found that activity in the right inferior frontal gyrus begins to increase during language generation. Our brains have enough plasticity to adapt to damage and change conformations, even as adults. Knowing that language processing usually occurs on the left side of the brain and response to danger generally occurs on the right does not comprehensively summarize our beings. Lateralization of the brain is still not well understood, and there are very few, if any, hard and fast rules of lateralization that actually make an impact on our behavior. We are still every bit as human and unpredictable as before, but we now understand a bit more of what makes us that way.

CARTOON

Aliens BY SPENCER KATZ

FEATURE