Creative scientific methods (with movie stars!)

As laypeople who read about science in newspapers and blogs, we’re often interested in results. Did the mice develop cancer? Sometimes, though, it’s not the results which offer the most food for thought, but the methods. How do you make a mouse smoke a cigarette?

Education level matters, even in movie star marriages

A new study in the Journal of Human Capital offers a nice example of what creative methods can do. The economist Gustaf Bruze studies how people select spouses. Not too surprisingly, people tend to select spouses with similar education levels: high school graduates marry other high school graduates, Ph.Ds marry other Ph.Ds.

Why? One possible explanation is proximity to similar folks. People spend a lot of time at school and at work. In both places, they’re very likely to meet people with education levels similar to their own. A different explanation is desire for financial stability. People might select a spouse whose education suggests that he or she will be a good provider.

It’s important to pinpoint the correct explanation because this marriage pattern has implications for social equality. People with higher education levels make more money. If they only marry peers with similar education levels, that money doesn’t move to other sectors of society.

To sort out these competing explanations, we need a method for examining what people do when neither proximity and financial stability matters. But that’s a real problem. Almost everyone works with colleagues who have similar education levels. And almost everyone’s income is related to their education.

Bruze came up with a creative solution. He studied movie actors. They differ from the rest of us in two key ways. One difference is proximity to similar folks. Movie actors don’t meet a homogenous group of people at work; instead, they meet a diverse group with a variety of education levels. (They also tend not to meet their spouses at school). The second difference concerns financial stability. Crucially, unlike most of us, movie actors do not earn wages that correlate with their formal education.

So Bruze analyzed data from 280 actors in the U.S. movie industry and got the following result. Movie actors marry movie actors with similar education levels — just like the rest of us! This suggests that neither proximity nor financial stability explains the marriage pattern. It seems, instead, that people simply have an inherent preference for spouses with similar education levels.

Bruze’s result may not surprise you much. Do people prefer similar people as spouses? Yes, they do. But his methodology should stimulate some creative thinking. How do you make a person take a spouse whose education suggests they won’t be a good provider? You don’t. Instead, you study someone who has already done so.

Related links

Scientific American: Movie star couples share educational backgrounds

Live Science: Want to marry a movie star?

Freakonomics: What can movie stars tell us about marriage and education?

ScienceNewsOnline: What can movie stars tell us about marriage?

References

Bruze, Gustaf. 2010. New evidence on the causes of educational homogamy. Department of economics, Aarhus University.

Clip art from Educational Technology Clearinghouse

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How to become a vampire

“There’s no literary term for the quality Twilight and Harry Potter (and The Lord of the Rings) share,” wrote Lev Grossman of Time magazine in 2008, “but you know it when you see it: their worlds have a freestanding internal integrity that makes you feel as if you should be able to buy real estate there.”

News from Thirsty Linguist

If there’s no literary term, we can test a scientific term instead: “narrative collective assimilation.” In a new study, Shira Gabriel and Ariana F. Young from the University at Buffalo asked 140 participants to spend thirty minutes reading a passage from either Twilight or Harry Potter and the Sorcerer’s Stone. Afterward, they measured the extent to which the participants psychologically assimilated to the collectives — vampires or wizards — described in each passage.

The results, to be published in an upcoming issue of Psychological Science, showed that the Twilight readers associated themselves with vampires, while the Harry Potter readers associated themselves with wizards. This finding held for both explicit measurements (“How sharp are your teeth?”) and implicit ones (the speed with which participants placed words like ME and FANGS into the same category).

Not all participants exhibited collective assimilation to the same degree. Gabriel and Young also administered standardized test items such as “When I join a group, I usually develop a strong sense of identification with that group.” Interestingly, participants who rated these items more highly also associated themselves more strongly with vampires or wizards after reading a passage. That is, participants who have stronger tendencies to identify with collectives in real life apparently transfer these tendencies to fiction.

Participants also completed a five-item questionnaire to indicate their mood, and a single-item questionnaire to indicate their life satisfaction (“Right now, in most ways, my life is close to ideal.”). Analysis of the results indicated that narrative collective assimilation correlated with better mood and increased life satisfaction. In other words, the more participants associated themselves with vampires or wizards after reading the passages, the better their mood and the higher their life satisfaction score.

Fiction is often viewed as an to escape from the real world, but Gabriel and Young conclude just the opposite. Fiction, they argue, offers an important opportunity to connect with social groups and participate in something bigger than ourselves.

So Grossman’s observation gets some confirmation from the laboratory: both Twilight and Harry Potter allow readers to climb inside a new world and “buy real estate”. Furthermore, doing so doesn’t just put you in a better mood — it actually makes you think that your entire life is better. That’s a striking finding.

Equally striking, though, is the fact that the results hold true for both books, despite the rather different critical receptions they have received.

Elizabeth Spires of The New York Times gave Stephenie Meyer’s Twilight a mixed review: “The premise of Twilight is attractive and compelling…but the book suffers at times from overearnest, amateurish writing. A little more ‘showing’ and a lot less ‘telling’ might have been a good thing.” Writing in the same publication, Michael Winerip had nothing but praise for Harry Potter and the Sorcerer’s Stone: Like Harry himself, J.K. Rowling “had wizardry inside, and has soared beyond her modest Muggle surroundings to achieve something quite special.”

The Salon.com reviews also draw a contrast between the books. Laura Miller critiques Meyer’s characterization of Bella, the human protagonist of Twilight: she is “more of a place holder than a character. She is purposely made as featureless and ordinary as possible in order to render her a vacant, flexible skin into which the reader can insert herself and thereby vicariously enjoy Edward’s chilly charms.” Writing in the same publication, Charles Taylor says simply: “I don’t think you can read 100 pages of Harry Potter and the Sorcerer’s Stone before you start feeling that unmistakable shiver that tells you you’re reading a classic.”

A close look at Gabriel and Young’s results actually does suggest that the participants assigned to read Harry Potter show greater effects of narrative collective assimilation than those assigned to read Twilight, particularly for the explicit measures. So Rowling’s prose may create a more measurably powerful experience for readers than Meyer’s. Still, the effects are present for both authors, and Gabriel and Young do not distinguish between them in their report.

We (or rather, I) like to think that the difference between amateurish writing and classic writing matters. But Gabriel and Young’s results potentially transcend this difference. Whether you read Twilight or Harry Potter, doing so makes you feel like part of a group. And that feeling is nothing short of transformative.

Related article

“Read a book, stay connected” in US News and World Report

References

Gabriel, Shira and Ariana F. Young. To appear. Becoming a vampire without being bitten: The narrative collective assimilation hypothesis. Psychological Science.

Meyer, Stephenie. 2005. Twilight. Little, Brown.

Rowling, J.K. 1997. Harry Potter and the Sorcerer’s Stone. Scholastic.

Wikipedia articles on Twilight and Harry Potter.

Artwork

Canteen clip art from Educational Technology Clearinghouse

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The Pulitzer Prize for Hypertext

Each year, the Pulitzer Prize committee supposedly bestows an award for distinguished fiction that deals with American life. But to my mind, this year’s committee bestowed an award for distinguished hypertext that demonstrates why we must read fiction in the Internet age.

Before I say why, let’s be clear: A Visit from the Goon Squad, which won the 2011 prize, isn’t hard to read. Author Jennifer Egan uses straightforward sentences. She portrays interesting characters that ring true, from aspiring teenage rock stars in San Francisco to loners fishing under Williamsburg Bridge. She sticks to familiar settings, like California and New York. And she talks a lot about rock and roll, which is fun.

Still, the reader has work to do. Goon Squad does not progress linearly through time. Each chapter takes place in a different year or decade, and Egan doesn’t tell you which one. She drops hints instead. Chapter 1: Sasha “hated the neighborhood at night without the World Trade Center.” Chapter 13: “the new buildings spiraled gorgeously against the sky, so much nicer than the old ones (which Alex had only seen in pictures)”. What year are we in? The reader must interpret these statements in order to build a chronology that connects one chapter to the next.

Nor does Good Squad present a unified voice. Third-person narration takes us through much of the book. But several estranged high school friends and a failed journalist each take a turn with first-person narration. A twelve-year old narrates her story with PowerPoint slides and demonstrates more facility with this medium than any businessperson I’ve ever seen. You (and I mean you) also take a turn in a chapter narrated in the second-person; your name is Rob and you die in a drowning accident, but wise readers knew your fate even before you did, based on clues presented earlier in the book. Who’s talking? The reader must interpret these voices in order to envision the characters, their passions, and their regrets. (Jonathan Bastian of NPR makes a similar point in his review).

So this book does not merely permit you to make connections, it demands that you do so. Unlike a mystery novel, however, it does not dictate how or when. As a result, A Visit from the Goon Squad is structurally incapable of being the same book twice. When I read it the first time, I connected the years and decades. I even got out the calculator and created a chronology of the thirteen chapters (this is so geeky, but according to my calculations, the book jumps from 2007, to 2006, 1979, 1973, 2005, 1997, 2002, 2007, 1998, 1992, 1989, and finally to the 2020’s in California and the 2020’s in New York City). When I read the book the second time, I connected the characters to one another; as in Vladimir Nabokov’s Lolita, many characters in Goon Squad have a twin or a mirrored identity, but you’ve got to look for them. When I read it the third time, I tossed all of this aside and found smaller themes. Plumbers, of all people, keep re-appearing in the book. So do figures from Greek mythology. So do large bodies of water, sometimes clean and sometimes polluted.

So why must we read fiction? Some people argue that good fiction serves an antidote to the Internet age. Good fiction, they might say, stops our relentless jumping from one site to another. It requires us to slow down and patiently follow a narrative from start to finish. But if you ask me, A Visit from the Goon Squad changes all that. Good fiction, we can now say, not only allows us but encourages us to jump from one site to another. Good fiction reveals how richly active our minds can be when we are forced to make connections on our own, rather than having them made for us. Good fiction embraces PowerPoint. Good fiction, despite all the good evidence to the contrary, looks a lot like the Internet. Congratulations to Jennifer Egan on winning the 2011 Pulitzer Prize for Hypertext.

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Book review: The Mind’s Eye, by Oliver Sacks

“I feel agitated now…I think I may have to sedate myself.” Oliver Sacks, a neurologist and well-known author, has just discovered a jet-black spot on the skin of his left shoulder. Two years earlier, a physician found a cancerous tumour on his retina, removed it with lasers, and administered radiation treatment. Now Sacks worries that the cancer has spread to his skin.

The black spot episode is just a tidbit about Sacks’s personality, although it’s not the only one that readers will find in in his latest book, The Mind’s Eye (Knopf, 2010), which explores the human experience of vision. As in some of his previous books, Sacks presents case histories of individuals suffering from neurological injury or disease, and uses these histories as a means to probe the capacities of the mind. Lilian Kallir, for example, is a pianist who loses the ability to read, even though the rest of her vision remains intact and, puzzingly, she can still write. Sacks follows Lilian’s story over a period of three years, describing the coping strategies she develops, such as color-coding items in her home, as well as the new talents that arise unexpectedly with her condition, such as the ability to re-arrange musical pieces in her mind without consulting a score. Howard Engel, featured in another case history, is a writer who also loses the ability to read, but he approaches his situation differently: he rejects audiobooks, refuses to give up the world of text, and painstakingly learns his ABCs all over again.

Lilian’s and Howard’s cases both suggest that the brain has a specific location dedicated to reading. But it is not at all obvious why this should be so. Unlike spoken language, which evolved over hundreds of thousands of years, written language is a relatively recent cultural invention that offered no survival advantage to humans in primitive societies. Plasticity offers a potential answer to this conundrum: we can and do use structures in the brain for purposes very different from those for which they evolved. Sacks casts a wide net to gather evidence for this idea. He describes case histories of nineteenth century neurologists, who treated patients with symptoms similar to Lilian’s and Howard’s. He cites evolutionary thinkers from Charles Darwin and Alfred Russel Wallace to Stephen Jay Gould and Elisabeth Vrba, tracing the history of the notion of “exaptation,” a biological adaptation which gets put to a new use. He presents key results from imaging studies which demonstrate that different areas of the brain are active during reading versus listening. And he summarizes a computational study of over 100 writing systems which shows that, despite their diversity, these systems share basic visual signatures which resemble those found in natural settings.

The Mind’s Eye thus offers narrative science writing of the most satisfying kind. We delight in pedagogical moments because Sacks weaves them seamlessly into the case histories. We get drawn into the topics of evolution, brain imaging, and computation because we want to follow people like Lilian and Howard. “Make characters the matter of your narrative,” advises James Shreeve in A Field Guide for Science Writers, “and let the science spill from their relations.” Sacks does precisely that.

Back to the black spot – and the need for sedation. After discovering the spot on his skin, Sacks visits Dr. Bickers, a dermatologist, the very next day. The spot isn’t cancerous. The dark color came from a little bit of bleeding, and should clear in a few days. So the black spot episode has nothing to do with Sacks’s eye tumor, and it therefore has nothing to do with vision, the purported topic of the book. But it has everything to do with Sacks as a character. Dr. Oliver Sacks needs sedation? He isn’t playing the role of the neurologist anymore. With cancer, he’s playing the patient.

This role reversal, which occurs in two of the book’s essays, “Face Blind” and “Persistence of Vision: A Journal”, works partly because of the manner in which Sacks develops his characters more generally. He specializes in describing the details which relate most directly to the mind and its capacities: One morning, for example, Howard opened up his morning paper. To his surprise, the headlines were in Serbo-Croatian. He suspected his friends, some of whom are pranksters, had played a practical joke on him. In reality, however, Howard has suffered a stroke which impairs his ability to recognize printed words.

But Sacks takes care to provide other details, even when the link to the mind proves less direct. At the initial visit to the emergency room, Howard is unable to pinpoint his relationship to the person who accompanied him there — his son. Returning home from the hospital three months later, Howard’s home looks peculiar to him, and the room which looks most peculiar is the one where he used to read most often — his office.

In order to develop full-blown characters in a narrative, Shreeve advises in A Field Guide for Science Writers, “you need to become intimate with their backgrounds, their hopes and fears, strengths and weaknesses, foibles, tics, grievances, grooming habits, and manners of speech, not to mention their method of hailing a taxi, removing a hair from their coffee cup, and unwrapping a candy bar.” With subtlety, Sacks does precisely that.

The most striking aspect of The Mind’s Eye, ultimately, is that Sacks treats himself the same way that he treats his other characters. This means that the “details” which he uses to portray his other characters now become vulnerabilities, but Sacks reveals them fearlessly. Again, some of these details relate directly to questions of the mind and its capacities: Sacks, who has always suffered from a serious difficulty in recognizing names and places, needs his guests to wear nametags when he throws a birthday party. He gets lost in the rain for two hours because he cannot find his own house. He recognizes his neighbors’ dogs, but not his neighbors themselves.

But other vulnerabilities leave a stronger emotional wake, partly because they do not connect directly to the topic of the mind. Sacks has a brother, Marcus. We learn that for a period of thirty-five years, they scarcely saw one another. Sacks has a work assistant, Kate. We learn that when Sacks goes to the doctor and receives a diagnosis of cancer, it’s Kate who accompanies him, not a partner, not a son or daughter. Oh, and on a lighter note: Sacks smokes cannabis, at least on occasion.

For a book about vision, these two portrayals of Oliver Sacks — as doctor and as patient — seem especially appropriate. The portrayals differ from one another, just as the visual images which reach our left eye versus our right eye also differ. The result, when we put the two together and compare them, is depth perception: or in other words, a far deeper understanding of the world than we could otherwise have.

References

Sacks, Oliver. 2010. The Mind’s Eye. New York: Alfred A. Knopf.

Shreeve, James. 2005. Narrative Writing. In Deborah Blum, Mary Knudson, & Robin Marantz Henig (eds.) A Field Guide for Science Writers. Oxford University Press.

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March Madness meets Malcolm Gladwell

By Anne Pycha

“Basketball’s decision-makers, it seems, are simply irrational,” wrote Malcolm Gladwell in 2006. On the eve of March Madness 2011, his words have taken on new meaning, thanks to a recent study conducted at Virginia Tech.

Each spring, 68 basketball teams participate in the NCAA Division I Men’s Basketball Tournament, also known as March Madness. Of these teams, 31 qualify automatically by winning their division championship. Remaining teams can participate only if they get hand-selected by an NCAA committee. This creates some drama and hand-wringing, especially for the “bubble” teams whose season performance might or might not warrant an invitaiton. The committee, which will announce its decisions this year on Sunday, March 13, consists of approximately ten athletic directors and sports commissioners from around the country. (That this year marks some changes; prior to 2011, only 64 teams participated in the tournament).

Virginia Tech professors Leanna House and Scotland Leman examined the decisions made by this committee from the 1993-1994 season to the present. Using Bayesian statistical methods, they found that a team’s Ratings Percentage Index (RPI) correlated strongly with an invitation to the tournament. The RPI includes three basic components: how often the team won during the season, how often their opponents won, and how often their opponents’ opponents won.

Sounds rational so far. But the RPI does not tell the entire story. House and Leman’s technical report suggests that “the committee may have a cognitive weighting scheme which does not agree perfectly with the RPI formula.” In other words, the decision-makers leave themselves some wiggle room.

So House and Leman examined an additional factor: marquee. A marquee team has a history of top performance in the tournament. The North Carolina Tar Heels offer a good example. In 1982, a player named Michael Jordan helped this team win the tournament championship. In subsequent years, the team won the championship several more times, most recently in 2009.

The NCAA Committee announces its decisions on "Selection Sunday" (this year, March 13)

House and Leman’s analysis showed that, given two teams with roughly equivalent RPIs, the committee was historically more likely to invite the marquee team. In 2000, for example, the Tar Heels finished the season with 31 wins and 21 losses. On the basis of their RPI alone, they had a 32% probability of being invited to the tournament. But the team’s marquee status boosted that probability to 85%. The committee did, in fact, invite them that year.

Non-marquee teams suffer the consequences of this decision-making. In 2010, the Virginia Tech Hokies finished the season with 33 wins and 13 losses. On the basis of their RPI, the Hokies had a 31% probability of being invited. Marquee status, if they had possessed it, would have boosted that probability to 83%. The committee did not invite them.

Virginia Tech coach Seth Greenberg raised the issue of marquee status out loud last year, providing House and Leman with the inspiration for their study. In March 2010, both the Hokies (33 wins, 13 losses) and the Tar Heels (20 wins, 17 losses) failed to receive an invitation to the tournament. Just afterwards, as reported on Techsideline.com, Greenberg asked: If North Carolina had Virginia Tech’s exact same resume, would they have been in the NCAA Tournament? The answer, it appears, is yes.

Making good decisions

So, is Malcolm Gladwell right? To some extent, the answer depends upon what we mean by a “rational” decision.

Gladwell’s 2006 article on basketball’s decision-makers, entitled “Game Theory” and published in The New Yorker, focused on the problem of ranking individual players. In it, Gladwell sang the praises of comprehensive rankings. Basketball games move so quickly and involve so many moves that observers simply cannot absorb everything. As a result, they construct arbitrary rankings that rely too heavily on how many points a player scored, ignoring important details like whether the player hogs the ball.

A truly comprehensive formula can correct for this, reflecting a player’s actual performance. Gladwell quotes approvingly from a book called Wages of Wins (which also has a related blog): “One can both play and watch basketball for a thousand years. If you do not systematically track what the players do, and then uncover the statistical relationship between these actions and wins, you will never know why teams win and why they lose.”

Of course, Gladwell himself has spilled a lot of ink arguing just the opposite. His book Blink: The Power of Thinking without Thinking claimed that we often make better decisions when we have less, rather than more, information. Gladwell gives an example from the art world. In 1983, the Getty Museum in Los Angeles considered buying a marble statue from the sixth century BC. Before the purchase, they hired a geologist who concluded, after an extensive investigation of the marble, that the statue was authentic. But after the purchase, several art experts visited the museum and concluded, after a moment’s viewing, that the statue was fake. As it turns out, the art experts were right. Largely on the basis of examples like these, Gladwell pursues the idea that “there can be as much value in the blink of an eye as in months of rational analysis.”

Malcolm Gladwell (with David Remnick of The New Yorker), February 15, 2011

Gladwell received many responses to the “Game Theory” article. As he recounts in Blink, a large number of his readers felt that statistics simply cannot substitute for an instinctive reaction to an athlete. Gladwell admits that they are partly right. He uses Michael Jordan as an example. At age 17, Jordan’s statistics did not put him at the top (yet). “What set Michael Jordan apart from his peers was his attitude and motivation. And those qualities can’t be measured with formal tests and statistics.” Ultimately, then, Gladwell advises that the best decisions combine both rational analysis and instinctive judgment.

Bringing instinctive judgments to statistics

Interestingly, although House and Leman remain neutral about the rationality of the NCAA committee’s decisions and do not advocate for any particular change, the general framework they use offers certain opportunities for taking Gladwell’s advice. One way to see this is by examining Bayes’s rule. In statistics, Bayes’s rule can incorporate rational analysis as well as real-world observations at the same time.

Statisticians use different methods to assign probabilities to the occurrence of events. But some of these methods use more information than others. Here is a simple example. Suppose you join a game of pick-up basketball among strangers in the park. Each team has five players. Early in the game, one player knocks the ball out of bounds. You see him do it, but since he’s a stranger and you just joined the game, you cannot remember if he is on your team or not. Given that there are two teams on the court, each with the same number of players, there is a 50% probability that the offending player is on your team.

Pickup basketball in Philadelphia, Summer 2010

That’s a fairly coarse calculation. But using Bayes’s rule, we can update that figure, based upon things we have observed in the real world. When you saw the player knock the ball out of bounds, you noticed that he was wearing a blue shirt. It so happens that on your team, four out of five players are wearing blue shirts. But on your opponents’ team, only one player is wearing a blue shirt. Instinctively, this suggests it’s pretty likely that the offending player is, in fact, on your team. Bayes’s rule allows us to incorporate that observation directly, updating the probability figure from 50% to 80%.

Importantly, with Bayes’s rule, it’s the actual observations we make in the real world which are used to update probabilities. You happened to notice a blue shirt, so that’s the knowledge you contribute to the statistical formula. But if you had noticed something else about the player who knocked the ball out of bounds — that his shoes were green, for example — Bayes’s rule would compute a different figure. In other words, the probability figure offers a substantial amount of wiggle room.

The Matthew effect

But the most troubling aspect of House and Leman’s results is not the general fact of wiggle room. We all know it exists. In fact, sports professionals and fans must somehow want wiggle room; if they didn’t, the NCAA could just use a computer algorithm to select all sixty-eight teams for March Madness. There would be no hand-wringing, and no such thing as a “bubble team.”

But a committee of actual human beings heightens the excitement considerably. It produces dramatic moments. And it produces funny quotes, like this one from Seth Greenberg last month on WRAL sports: “Well, you look up ‘on the bubble’ in the dictionary and you’ll see my picture also. I am Mr. Bubbalicious.”

No, the truly troubling aspect of these results concerns the “Matthew effect.” Coined by sociologist Robert Merton and discussed by Gladwell in his book Outliers: The Story of Success, this effect owes its name to a passage from the gospel of Matthew: the rich get richer and the poor get poorer.

The marquee factor uncovered by House and Leman demonstrates exactly that. The Tar Heels, by basketball standards, are rich. They possess the legacy of Michael Jordan. They have won more games than almost any other team in college basketball history. And these facts, which constitute their “marquee”, help them get richer still, increasing the probability of an NCAA invitation and providing them with another opportunity to succeed.

Outliers critiques the societal forces that give rise to the Matthew effect. “To build a better world,” writes Gladwell, “we need to replace the patchwork of lucky breaks and arbitrary advantages that today determine success…with a society that provides opportunities for all.”

If the marquee factor were eliminated, in other words, we could have a more equitable NCAA tournament. Worthwhile teams like the Virginia Tech Hokies would stand a fair chance of getting invited, and this invitation would provide them with further opportunities to succeed. Shouldn’t a guy who refers to himself as “Mr. Bubbalicious” get a fair shake?

References

Berri, David J., Martin B. Schmidt, &  Stacey L. Brook. 2007. Wages of Wins: Taking Measure of the Many Myths of Modern Sport. Stanford Business Books.

House, Leanna & Scotland Leman. 2011. Life on the bubble: Who’s in and who’s out? Technical report, Virginia Tech.

Gladwell, Malcolm. 2006. Game theory. The New Yorker.

Gladwell, Malcolm. 2005. Blink: The Power of Thinking without Thinking. New York: Back Bay Books / Little, Brown and Company. eBook edition: April 2007.

Gladwell, Malcolm. 2008. Outliers: The Story of Success. New York: Little, Brown and Company.

Hokiesports.com

TarHeelBlue.com

Techsideline

Virginia Tech News

WRAL sports

 

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Book review: Portraits of the Mind

No one feels guilty for skipping the methods section of a scientific paper. The dry prose describes procedures that the authors used to obtain their data, dutifully mentioning every detail such that another researcher could conceivably replicate the experiment from start to finish. Most readers focus instead on the discussion section, which summarizes the results, offers a meaningful interpretation of them, and makes predictions for future experiments. By comparison, the methods section holds little allure.

Portraits of the Mind, a new book by Carl Schoonover, aims to change that. With a collection of stunning images that illustrate a wide range of research techniques in neuroscience, it invites lay readers to revisit the methods section. Consider the image of a monkey’s visual cortex which, eerily, has a smiley face superimposed on it. The smiley face is no accident. To produce the image, researchers aimed a high-speed video camera at the monkey’s visual cortex, an area in the back of the brain that processes visual information. The camera captured small increases in blood volume, which correlate with increases in brain activity. Crucially, the monkey was looking at a picture of a smiley face when researchers snapped the photo. The reproduction of the smiley face in the cortex demonstrates a key feature of the visual system: adjacent objects in the real world occur as adjacent representations in the brain.

Published by Abrams, Portraits of the Mind has the look and feel of a coffee-table art book. It offers short texts to accompany each image and concise essays, contributed by eight specialists, to introduce each chapter. Schoonover knows that some readers will want to enjoy the images on their own terms: “If you feel your eyes glaze over where the text gets complicated and qualified, fear not, just move on — you won’t be missing much.” This statement, however, does a disservice not only to Schoonover’s careful texts but also to the complexity of the images, most of which require more work to interpret than the smiley face. In one image, for example, a set of neurons in the retina literally glow in the dark; curiously, the dendrites (branches) of these neurons do not reach out at random, but all align in the same vertical direction. To produce the image, researchers used a genetic copy-and-paste method. They inserted a jellyfish gene, which produces a florescent green color, into a mouse’s DNA, and switched on the gene only in a subset of neurons. The result is aesthetically pleasing, to be sure, but also reveals a striking interplay of form and function that we can glean only from the text: the illuminated and vertically aligned neurons happen to be precisely those which, in the retina, detect objects that move in an upward direction.

Portraits offers concise descriptions of many more methods, including revolutionary techniques from the late 1800s as well as a slew of more recent developments from the 2000s. The list is long and diverse, but also, as the book points out, troubling: these methods, impressive as they are, actually produce so much data that no model can yet make sense of it all. The “Brainbow” method offers a case in point. Brainbow also works with fluorescence, but it uses DNA sequences for multiple different colors, such that a given neuron can glow not just green, but red, blue, chartreuse, yellow, or orange. This method allows researchers to distinguish individual neurons from each other despite the fact that they are tightly packed together (thus, a green neuron can be distinguished from its neighbor, which might be red, and so on) and produces some of the most striking images in the book. It does not, however, provide any clue as to why one specific neuron forms a connection with another neuron; furthermore, the actual color assumed by a given neuron is not meaningful, but random, making the images difficult to decipher.

Brainbow and other methods are thus “limited, paradoxically, by the dizzying volumes of data they generate, which must then somehow be interpreted” (emphasis mine). Two possible approaches to the interpretation problem recur in the book; the tension between them is apparent in Schoonover’s texts as well as Terrence Sejnowski’s introduction to Chapter 6, “The Brain as Circuit”. The first approach is to simply wait for a genuis: eventually, someone with a special vision will create a new model that radically alters our interpretation of neuroscientific data. It’s happened before. In the late 1800s and early 1900s, Spanish scientist Santiago Ramón y Cajal combined newly developed methods for visualizing individual neurons under a microscope with his own peculiar artistic talent. His efforts led to the formulation of the Neuron Doctrine — the now widely-accepted idea that individual cells form the basic computational unit of the nervous system — and earned him the Nobel Prize for Medicine in 1906 along with Camillo Golgi. (Golgi, incidentally, vehemently disagreed with the Doctrine).

The second approach to the interpretation problem involves machines, not people. Computers can detect patterns in large data sets that no human could possibly see on his or her own. If we let computers crunch the numbers, we might eventually build connectomes, or wiring diagrams that indicate how each neuron connects to every other neuron. Researchers have already created a nearly complete connectome for the worm C. elegans, whose nervous system contains just 302 neurons. With increased computational capacity, connectomes for other animals and humans might eventually become possible as well. This approach has the obvious advantage that non-geniuses can still produce valuable work, by programming computers to extend findings from smaller data sets to increasingly larger ones.

Sejnowski, a professor at the Salk Instiute for Biological Studies in San Diego, pioneered the computational approach to neuroscience. His essay in Portraits describes how, in 1980, he showed that an artificial neural network could learn some surprisingly difficult tasks, such as pronouncing English words. Today’s computers can create far more sophisticated neural networks that simulate not just individual neurons, but also fine dendritic branching and multiple synapses. Yet even Sejnowski admits that the computational approach, for all of its advantages, falls somewhat short: “…even if we could reproduce all the anatomical details and signals in a brain, this wealth of knowledge would not in itself explain how a brain functions, or goes awry. What we need is a twenty-first-century Cajal who can understand the function of these circuit diagrams by simulating the signals as they are processed by the circuits themselves.”

In a book focused on methods, the desire for genius strikes a funny note. Dry as it is, the methods section of scientific papers permits any researcher to replicate the experiment — no genius required. Of course, the researcher still needs certain technical skills, as well as background knowledge, but she need not be the next Cajal. After replication, the researcher can propose novel interpretations for the data and variations on the methods used to obtain it. In other words, she can advance the state of our knowledge, one step at a time.

Ultimately, though, the egalatarian spirit prevails in Portraits of the Mind. For readers seeking eye candy, the book delivers nothing short of beauty. For readers seeking to learn something new, the book offers a great introduction to neuroscience — no genius, and no technical skills, required.

Reference

Schoonover, Carl. 2010. Portraits of the Mind: Visualizing the Brain from Antiquity to the 21st Century. New York: Abrams.

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The trouble with archives, as recounted in film

Filmmaker Jenny Perlin took the inspiration for her recent series The Perlin Papers from an archive at Columbia University. An archive seems like straightforward affair — it’s a collection of documents, which might be dusty with age. But recent events have given us an opportunity to reconsider the importance of archives, as well as the historical forces which shape them. Last November, for example, WikiLeaks published hundreds of thousands of U.S. embassy cables on its website. The contents of the cables made headlines, but so did the person of Julian Assange, founder of WikiLeaks. The message: this archive is a collection of documents, but it is also the product of actual humans.

At the Columbia archive, Perlin examined many of the 250,000 pages related to the cold-war espionage case of Julius and Ethel Rosenberg. Her eight short films do not actually focus on the Rosenbergs, nor on the personality behind the archive, lawyer Marshall Perlin (a distant relative of Jenny’s). Instead, they explore acts of document preparation during the 1950s. We listen to muffled speech and witness the subsequent attempts at transcription. We see typewriter keys go astray. The message: this archive is the product of actual humans, and these humans worked with imperfect tools.

Still from “Mimeograph”. Film by Jenny Perlin, 16mm, color, sound , 19:50, 2010. Production still by Cassandra Guan 2010. Courtesy Jenny Perlin and Galerie M+R Fricke Berlin

In the film “Transcript,” FBI agents position themselves in the hallway of a New York apartment building in order to eavesdrop on a dinner party held by friends of the Rosenbergs. Snippets of clear conversation travel through the apartment walls from time to time, tempting the listener into constructing meaning. But for the most part, we hear long stretches of speech sounds that are frankly uninterpretable. In “Inaudible,” we see the transcript of this conversation as produced by the FBI. Most lines consist of a single word: inaudible.

In “Mimeograph,” two women spend their work day typing up FBI documents related to the Rosenberg case. The relentless din of typewriter keys leaves no doubt that we are back in the pre-digital era.  The women fix minor typos with a pencil. They fix larger typos with correction paper, which covers the error with white ink, one letter at a time. To create duplicates of their documents, they use mimeograph sheets, which would preserve a record of both the original errors and their subsequent corrections, laid on top of one another.

The films thus problematize the notions of archive and document and, in so doing, also problematize spoken and written communication more generally. Linguists often struggle when explaining these areas of research to a broader audience because speaking and writing seem relatively effortless to most of us. By filtering speech sounds through the walls of an apartment building, and subjecting printed words to wayward typewriter strokes, The Perlin Papers demonstrate that barriers to accurate communication exist everywhere. The research challenge for linguistics, then, is to characterize the cognitive capabilities that allow people to circumvent these barriers as often as they do.

The Perlin Papers, which played at Location One in New York City on January 27, will play again on June 1, 2011 at the Toronto International Film Festival. Until then, you can check out other projects by Jenny Perlin (disclaimer: she’s a friend), which include An Exchange with Sol Lewitt, at Mass MoCA in North Adams, Mass. and Cabinet in Brooklyn from January 23 to March 31, 2011, and Found in Translation at the Guggenheim Museum in New York, from February 11 to May 1, 2011.

 

 

 

 

 

 

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