The Frontal Cortex

The Reading Brain

Fri, 20 Nov 2009 15:10:10 -0500

I've got a review of Stanislas Dehaene's new book, Reading in the Brain, over at the Barnes and Noble Review:

Right now, your mind is performing an astonishing feat. Photons are bouncing off these black squiggles and lines -- the letters in this sentence -- and colliding with a thin wall of flesh at the back of your eyeball. The photons contain just enough energy to activate sensory neurons, each of which is responsible for a particular plot of visual space on the page. The end result is that, as you stare at the letters, they become more than mere marks on a page. You've begun to read.
Seeing the letters, of course, is just the start of the reading process. As the neuroscientist Stanislas Dehaene reveals in his fascinating new book, Reading in the Brain, the real wonder is what happens next. Although our eyes are focused on the letters, we quickly learn to ignore them. Instead, we perceive whole words, chunks of meaning. (The irregularities of English require such flexibility. As George Bernard Shaw once pointed out, the word "fish" could also be spelled ghoti, assuming that we used the gh from "enough," the o from "women," and the ti from "lotion.") In fact, once we become proficient at reading, the precise shape of the letters -- not to mention the arbitrariness of the spelling -- doesn't even matter, which is why we read word, WORD, and WoRd the same way.

In this clearly written summary of the field, Dehaene is primarily interested in two separate mysteries. The first mystery is how the individual human brain learns to read. What changes take place inside our head between kindergarten and second grade, when most of us start to take literacy for granted? How do we go from sounding out syllables, carefully parsing the phonetics of each word, to becoming fluent readers? And how does this incredibly complicated act become automatic, so that evn ths sntnce cn b quikly undrstd?

Dehaene begins by introducing the reader to the "letterbox area," a small bit of brain just behind the left ear. The crucial role of this cortical part was first revealed by Mr. C, a 19th-century neurological patient who, after a mild stroke, lost the ability to read. What made Mr. C's case so peculiar is that his vision was perfectly fine; he could make sense of objects and faces and even numbers. However, when he opened up a book or glanced at a newspaper, the letters on the page were utterly inscrutable, a mess of inchoate lines and curves. "He [Mr.C] thinks that he has lost his mind," his doctor dryly noted.

Subsequent studies of patients with pure alexia -- they can see everything but written language -- have located the specific contours of the letterbox area. Not surprisingly, it takes up a significant chunk of our visual cortex, as the invention of the alphabet seems to have usurped brain cells previously devoted to object recognition. (Dehaene refers to this process as "neuronal recycling.") He also speculates that, while "learning to read induces massive cognitive gains," it also comes with a hidden mental cost: because so much of our visual cortex is now devoted to literacy, we're less able to "read" the details of natural world.

But reading isn't just about seeing -- we still have to imbue those syllabic sounds with meaning. This is why, once the letterbox area deciphers the word -- this takes less than 150 milliseconds -- the information is immediately sent to other brain areas, which help us interpret the semantic content. Such a complex act requires a variety of brain areas scattered across both hemispheres, all of which must work together to make sense of a sentence. If any of these particular areas are damaged, people tend to lose specific elements of language, such as the ability to conjugate verbs or decipher metaphors.

One of the most intriguing findings of this new science of reading is that the literate brain actually has two distinct pathways for reading. One pathway is direct and efficient, and accounts for the vast majority of reading comprehension -- we see a group of letters, convert those letters into a word, and then directly grasp the word's meaning. However, there's also a second pathway, which we use whenever we encounter a rare and obscure word that isn't in our mental dictionary. As a result, we're forced to decipher the sound of the word before we can make a guess about its definition, which requires a second or two of conscious effort.

The second major mystery explored by Dehaene is how reading came to exist. It's a mystery that's only deepened by the recency of literacy: the first alphabets were invented less than 4,000 years ago, appearing near the Sinai Peninsula. (Egyptian hieroglyphic characters were used to represent a Semitic language.) This means that our brain wasn't "designed" for reading; we haven't had time to evolve a purpose-built set of circuits for letters and words. As Deheane eloquently notes, "Our cortex did not specifically evolve for writing. Rather, writing evolved to fit the cortex."

Deheane goes on to provide a wealth of evidence showing this cultural evolution in action, as written language tweaked itself until it became ubiquitous. In fact, even the shape of letters -- their odd graphic design -- has been molded by the habits and constraints of our perceptual system. For instance, the neuroscientists Marc Changizi and Shinsuke Shimojo have demonstrated that the vast majority of characters in 115 different writing systems are composed of three distinct strokes, which likely reflect the sensory limitations of cells in the retina. (As Dehaene observes, "The world over, characters appear to have evolved an almost optimal combination that can easily be grasped by a single neuron.") The moral is that our cultural forms reflect the biological form of the brain; the details of language are largely a biological accident.

Deheane ends the book with a discussion of education -- he's a supporter of phonics and ridicules the whole-language method, "which does not fit with the architecture of our visual brain." It's an interesting chapter, and it's always nice to see scientists grapple with the practical implications of their work, but the most compelling themes of the book remain rooted in basic science. As Deheane and others have demonstrated, the brain is much more than the seat of the soul -- it's also the fleshy source of our culture. By studying the wet stuff inside our head, we can begin to understand why this sentence has this structure, and why this letter, this one right here, has its shape.

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Luxury Goods

Thu, 19 Nov 2009 12:59:34 -0500

Saks and Barneys and the rest of those luxury retailers have discovered that nothing destroys a luxury brand like a sale:

All around Saks Fifth Avenue, merchandise is sold out. The $2,520 Marni shearling vest? Gone. The $5,295 Brioni leather bomber jacket? Only one left. The $1,995 over-the-knee Christian Louboutin boots?
The $1,995 over-the-knee Christian Louboutin boots at Saks have sold out, unless you can wear the only pair left -- a size 11. "All gone, except for this," said Nick Passerelli, a Saks employee, dangling a size 11 boot from his fingers.

After a brutal year in which the nation's luxury retailers were forced to offer their wares at stunning discounts, they are trying to get their magic back. And they may have found a way: deliberately running low on merchandise.

Saks, the chic Manhattan department store, is a prime example. Its inventory is down by double digits compared with last year. That is partly a response to lower demand, of course, but it is also a business strategy aimed at weaning consumers from deep discounts. By carrying fewer goods and selling them at full price, Saks is essentially telling customers: buy it now or live without it.

"Upscale stores want to train the customer that luxury equals exclusivity and that they cannot assume they can wait and they're able to buy it on sale," said William S. Taubman, chief operating officer of Taubman Centers, a mall developer and owner.

This is bad news for people like me, who subsist on online sales. But I think it's clearly good retail policy, if only because the allure of luxury items - the irrational desire that makes us want to spend two thousand dollars on a boot - is entirely rooted in their rarity. When you put something on sale, you suggest the opposite: the object is too abundant, which is why it requires a discount.

The reason luxury items are damaged by abundance is because they are "positional goods," since part of their appeal is that they signal your social position. A Christian Louboutin boot doesn't protect your feet better than a L.L. Bean winter boot - in fact, it's probably far less functional - but it does convey a sense of identity. The fancy shoe instantly informs strangers that you're the type of person who can afford (and appreciate) such splurges, and also knows how to find something so rare. (This is an under-appreciated perk of capitalism: it allows us express ourselves with things, defining our personality with clothes, computers and brands. I'm not defending this practice - I'm simply noting that it works, and that people the world over rely on mass-produced objects to remind themselves who they are.) Last year, I talked to Jonah Berger about the quirks of luxury retail brands, and how even seemingly subtle brands - such as Prada t-shirts without the Prada logo - are still all about exclusivity:

LEHRER: You've pointed out that expensive brands come with a subtle paradox: consumers spend lots of money on these brands (such as Prada or Armani) but these high-end products are actually less likely to contain clear brand markers. Although that $20 Tommy Hilfiger polo shirt will almost certainly contain a Hilfiger logo, that $100 Prada t-shirt won't advertise its provenance. Why, then, do consumers spend so much money on expensive brands?
BERGER: Communication. Consumers want other people to think certain things about them, and so they wear clothes that communicate particular identities. Conspicuous consumption, or spending lots of money on visible goods, is a good way to try and communicate wealth, but this signal breaks down when any wannabe can buy a certain car or handbag. What were once status symbols become just aspirational markers rather than the real thing. Consequently, insiders may engage in more inconspicuous consumption to signal only to others in the know. Such subtle signals may be almost invisible to the mainstream, and this helps maintain their cache.

LEHRER: In a 2007 paper, you note that "Manhattanites stopped wearing mesh trucker hats when the bridge-and-tunnel crowd adopted them." In other words, the urbane crowd abandoned a fad once too many of the "wrong" people adopted it. You argue that this kind of switch is because consumers choose products that communicate a "desired identity." Is this true of all product domains? Or are certain consumer items more intertwined with our identity than others? If so, why? Why are hats more reflective of our identity than, say, backpacks?

BERGER: Certain domains are definitely more symbolic of identity and this fact has a lot to do with utility and function. People buy detergent based on what cleans the best, and consequently that choice doesn't say much about who they are. Shirt choice, however, is based much less on function. Two different colored shirts do an equally good job of being shirts, so observers are more likely to attribute someone's choice to something about their identity. Similarly, things that violate functionality are more likely to be seen as identity-relevant. Wearing sunglasses indoors makes it harder to see. Wearing a scarf in the summer is unnecessary. Consequently, these behaviors are more likely to be seen as signals of identity because they have little functional value.

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Fourth Down

Tue, 17 Nov 2009 17:09:36 -0500

Bill Belichick has never been the most popular coach in the NFL, but his Sunday night decision to go for it on 4th and 2 on his own 28 with two minutes remaining in the fourth quarter has even his fans crying foul. I bring up this football decision not because I'm interested in a debate - as a Pats fan, the last five minutes of that game were excruciating - but because I think it illustrates the difficulty of making rational decisions, even when the evidence supports the call.

I've blogged about the research of UC Berkeley economist David Romer before, but his basic thesis, based on an exhaustive statistical analysis of 4th down scenarios, is that NFL coaches are irrationally risk-averse. They punt the ball way too frequently and kick far too many field goals.

Belichick was an econ major, and has expressed a familiarity with Romer's research. Nicholas Beaudrot has persuasively shown how, from this econometric perspective, Belichick's bizarre decision actually makes perfect sense:

On 4th down, with 2 yards or fewer to go, New England has gained a first down on approximately 66% of its attempts with Tom Brady as quarterback. The Colts had one timeout. If the Patriots gain a first down, the game ends; they can slowly walk to burn a few seconds, then take a knee on each down to end the game. If they don't gain a first down, the Colts would still need to score a touchdown to win the game. Let's give the Colts a probability P of getting the six if the ball starts at the 28 yard line. So if the Patriots try for the first, their chance of losing is
(Probability of 4th down failure) x
(Probability of Colts scoring a TD from the 28 Yard line) = 0.33P

The average New England punt nets about 40 yards. Let's give the Colts a probability Q of scoring a TD on a driving starting at the Indianapolis 32. Then, the chance of the Patriots losing is simply Q. For Belichick's decision to make sense, we just have to believe that he gave his team a lower chance of losing. In math terms, that would mean 0.33P < Q. Doing some algebra leaves you with P < 3Q. In other words, for the Patriots to have made the right decision, we only have to believe the Colts odds of scoring a TD on a drive starting 28 yards from the end zone are less than three times the odds of the same outcome starting from 68 yards out. The win probability graph for the game suggests that, given 1st-and-10 from New England's 29, the Colts had roughly a 51% chance of winning in the actual situation. We have to believe that their chances under the punt scenario were above 17% for Belichick to have made a bad good decision. Considering the Colts' have scored touchdowns on 30% of their offensive possessions, my guess is that this was a good one.

The reason I bring up this analysis is to demonstrate that even defensible decisions can have wrenching emotional consequences. Belichick's call might have been statistically correct, but it felt horribly wrong.

And this kind of contradiction isn't just relevant for football coaches. Just consider health care: the only way we're ever going to reduce medical costs is to restrict procedures that haven't passed evidence-based efficacy tests. Maybe that means 40 year old women don't get mammograms, or that we treat prostrate cancer less aggressively, or that we stop performing spinal fusion surgeries. Although there's solid evidence to question all of these medical options, such changes provoke intense debate. Why? Because our emotions don't understand statistics. Because when we have back pain we want an MRI. Because when it's our father with prostate cancer we want the most aggressive possible treatments. And so on.

The point is that there's often an indefatigable gap between the rigors of cost-benefit analyses and the emotional hunches that drive our decisions. We say we want to follow the evidence, but then the evidence rubs against a bias like loss aversion, and so we make an exception. We'll follow the evidence next time.

So here's my cheeky proposal for lowering the cost of health care: Put Belichick in charge of Medicare. Nobody likes him anyways, and he's clearly able to follow the math even when it feels like a mistake.

PS. Razib addresses a similar issue from a slightly different angle.

Update: Here's more evidence that Belichick's decision was eminently rational, and made them 9 percent more likely to win than punting the ball.

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The Tiger Woods Effect

Tue, 17 Nov 2009 12:42:53 -0500

Success is intimidating. When we compete against someone who's supposed to be better than us, we start to get nervous, and then we start to worry, and then we start to make stupid mistakes. That, at least, is the lesson of a new working paper by Jennifer Brown, a professor at the Kellogg school.

Brown demonstrated this psychological flaw by analyzing data from every player in every PGA tournament from 1999 to 2006. The reason she chose golf is that Tiger Woods is an undisputed superstar, the most intimidating competitor in modern sports. (In 2007, Golf Digest noted that Woods finished with 19.62 points in the World Golf Ranking, more than twice as many as his closest rival. This meant that "he had enough points to be both No. 1 and No. 2.") Brown also notes that "golf is an excellent setting in which to examine tournament theory and superstars in rank-order events, since effort relates relatively directly to scores and performance measures are not confounded by team dynamics." In other words, every golfer golfs alone.

Despite the individualistic nature of the sport, the presence of Woods in the tournament had a powerful effect. Interestingly, Brown found that playing against Woods resulted in significantly decreased performance. When the superstar entered a tournament, every other golfer took, on average, 0.8 more strokes. This effect was even more pronounced when Woods was playing well. Based on this data, Brown calculated that the superstar effect boosted Woods' PGA earnings by nearly five million dollars.

Brown argues that this phenomenon is caused when "competitors scale back their effort in events where they believe Woods will surely win." After all, why waste energy and angst on an impossible contest?

That hypothesis is certainly possible, but I'd argue that the superstar effect has more to do with "paralysis by analysis" than with decreased motivation. I'd bet that playing with Tiger Woods makes golfers extra self-conscious, and that such self-consciousness leads to choking and decreased performance. The problem, then, isn't that golfers aren't trying hard enough when playing against Tiger - it's that they're trying too hard. I wrote about this mental challenge in the London Observer earlier this year:

Scientists have begun to uncover the causes of choking, diagnosing the particular mental differences that allow some people to succeed while others wither in the spotlight. Although it might seem like an amorphous category of failure, their work has revealed that choking is triggered by a specific mental mistake: thinking too much.
The sequence of events typically goes like this: when people get nervous about performing, they become self-conscious. They start to fixate on themselves, trying to make sure that they don't make any mistakes. This can be lethal for a performer. The bowler concentrates too much on his action and loses control of the ball. The footballer misses the penalty by a mile. In each instance, the natural fluidity of performance is lost; the grace of talent disappears.

Sian Beilock, a professor of psychology at the University of Chicago, has helped illuminate the anatomy of choking. She uses golf as her experimental paradigm. When people are learning how to putt, it can seem daunting. There are just so many things to think about. Golfers need to assess the lay of the green, calculate the line of the ball, and get a feel for the grain of the turf. Then they have to monitor their putting motion and make sure that they hit the ball with a smooth, straight stroke. For an inexperienced player, a golf putt can seem unbearably hard, like a life-sized trigonometry problem.

But the mental exertion pays off, at least at first. Beilock has shown that novices hit better putts when they consciously reflect on their actions. The more time they spend thinking about the putt, the more likely they are to hole the ball. By concentrating on their game, by paying attention to the mechanics of their stroke, they can avoid beginner's mistakes.

A little experience, however, changes everything. After golfers have learned how to putt - once they have memorised the necessary movements - analysing the stroke is a waste of time. The brain already knows what to do. It automatically computes the slope of the green, settles on the best putting angle, and decides how hard to hit the ball. Bradley Hatfield, a professor of kinesiology and psychology at the University of Maryland, has monitored the brain wave activity of expert athletes during performance. (Because the subjects have to wear a bulky plastic cap full of electrodes, Hatfield can only study golfers, archers and Olympic rifle shooters.) While the brain waves of beginners show lots of erratic spikes and haphazard rhythms - this is the neural signature of a mind that is humming with conscious thoughts - the minds of expert athletes look strangely serene. When they are performing, they exhibit a rare mental tranquility, as their brain deliberately ignores interruptions from the outside world. This is neurological evidence, Hatfield says, of "the zone", that trance-like mindset which allows experts to perform at peak levels. (As the corporate motto says, the best athletes don't think: they just do it.)

Beilock's data further demonstrate the benefits of relying on the automatic brain when playing a familiar sport. She found that when experienced golfers are forced to think about their putts, they hit significantly worse shots. All those conscious thoughts erase their years of practice. "We bring expert golfers into our lab, we tell them to pay attention to a particular part of their swing, and they just screw up," Beilock says. "When you are at a high level, your skills become somewhat automated. You don't need to pay attention to every step in what you're doing."

This is what happens when people "choke". The part of their brain that monitors their behaviour starts to interfere with actions that are normally made without thinking. Performers begin second guessing skills that they have honed through years of practice. The worst part about choking is that it tends to spiral. The failures build upon each other, so a stressful situation is made more stressful.

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Expertise

Mon, 16 Nov 2009 09:28:33 -0500

The WSJ discovers the unreliability of wine critics, citing the fascinating statistical work of Robert Hodgson:

In his first study, each year, for four years, Mr. Hodgson served actual panels of California State Fair Wine Competition judges--some 70 judges each year--about 100 wines over a two-day period. He employed the same blind tasting process as the actual competition. In Mr. Hodgson's study, however, every wine was presented to each judge three different times, each time drawn from the same bottle.
The results astonished Mr. Hodgson. The judges' wine ratings typically varied by ±4 points on a standard ratings scale running from 80 to 100. A wine rated 91 on one tasting would often be rated an 87 or 95 on the next. Some of the judges did much worse, and only about one in 10 regularly rated the same wine within a range of ±2 points.

Mr. Hodgson also found that the judges whose ratings were most consistent in any given year landed in the middle of the pack in other years, suggesting that their consistent performance that year had simply been due to chance.

It's easy to pick on wine critics, as I certainly have in the past. Wine is a complex and intoxicating substance, and the tongue is a crude sensory muscle. While I've argued that the consistent inconsistency of oenophiles teaches us something interesting about the mind - expectations warp reality - they are merely part of a larger category of experts vastly overselling their predictive powers.

Look, for instance, at mutual fund managers. They take absurdly huge fees from our retirement savings, but the vast majority of mutual funds in any given year will underperform the S&P 500 and other passive benchmarks. (Between 1982 and 2003, there have only been three years in which more than 50 percent of mutual funds beat the market.) Even those funds that do manage to outperform the market rarely do so for long. Their models work haphazardly; their success is inconsistent.

Or look at political experts. In the early 1980s, Philip Tetlock at UC Berkeley picked two hundred and eighty-four people who made their living "commenting or offering advice on political and economic trends" and began asking them to make predictions about future events. He had a long list of pertinent questions. Would George Bush be re-elected? Would there be a peaceful end to apartheid in South Africa? Would Quebec secede from Canada? Would the dot-com bubble burst? In each case, the pundits were asked to rate the probability of several possible outcomes. Tetlock then interrogated the pundits about their thought process, so that he could better understand how they made up their minds. By the end of the study, Tetlock had quantified 82,361 different predictions.

After Tetlock tallied up the data, the predictive failures of the pundits became obvious. Although they were paid for their keen insights into world affairs, they tended to perform worse than random chance. Most of Tetlock's questions had three possible answers; the pundits, on average, selected the right answer less than 33 percent of the time. In other words, a dart-throwing chimp would have beaten the vast majority of professionals. Tetlock also found that the most famous pundits in Tetlock's study tended to be the least accurate, consistently churning out overblown and overconfident forecasts. Eminence was a handicap.

But here's the worst part: even terrible expert advice can reliably tamp down activity in brain regions (like the anterior cingulate cortex) that are supposed to monitor mistakes and errors. It's as if the brain is intimidated by credentials, bullied by bravado. The perverse result is that we fail to skeptically check the very people making mistakes with our money. I think one of the core challenges in fixing our economy is to make sure we design incentive systems to reward real expertise, and not faux-experts with no track record of success. We need to fund scientists, not mutual fund managers.

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Dopamine and Future Forecasting

Fri, 13 Nov 2009 11:20:36 -0500

Ed Yong has a typically excellent post on a new paper that looks at how manipulating dopamine levels in the brain can change our predictions of future pleasure:

Tali Sharot from University College London found that if volunteers had more dopamine in their brains as they thought about events in their future, they would imagine those events to be more gratifying. It's the first direct evidence that dopamine influences how happy we expect ourselves to be.
Sharot recruited 61 volunteers and asked them to say how happy they'd feel if they visited one of 80 holiday destinations, from Greece to Thailand. All of the recruits were given a vitamin C supplement as a placebo and 40 minutes later, they had to imagine themselves on holiday at half of the possible locations. After this bout of fanciful daydreaming, they had to take another pill but this time, half of them were given L-DOPA instead of the placebo. Again, they had to imagine themselves in various holiday spots.

The next day, Sharot brought the volunteers back. By this time, they would have broken down all the L-DOPA in their system. She asked them to choose which of two destinations they'd like to go to, from the set that they had thought about the day before. Finally, they rated each destination again.

By the end of the experiments, they perceived their imaginary holidays to be more enjoyable if they had previously thought about the locations under the influence of L-DOPA (while vitamin C, as predicted, had no effect). The implication is clear: think about the future with more dopamine in the noggin and you'll imagine that you have a better time.

As I've noted before, the popular caricature of dopamine - it's the hedonistic molecule in the brain, activated by sex, drugs and rock and roll - is slightly misleading. Dopamine neurons, it turns out, don't care about pleasure per se - they're much more interested in predicting pleasure, and then comparing our predictions to the actual event. The transactions of dopamine are largely about learning - finding a way to maximize our rewards - and not about mere decadence.

What I find so interesting about this experiment is that it neatly confirmed this theory of computational neuroscience. After all, the subjects didn't feel happier after popping a pill of L-DOPA - boosting dopamine levels didn't lead to instant gratification, like Huxley's soma. Instead, it merely altered their predictions of future happiness.

But here's the funny thing about those predictions: they tend to correlate pretty accurately with our actual experience. If you think you're going to have a good time on vacation, then you probably will, just as we tend to enjoy foods and beverages and products that we expect to enjoy. (This is the consumer version of the placebo effect.) Here's how I described similar phenomena in How We Decide:

Baba Shiv, a neuroeconomist at Stanford, supplied a group of people with Sobe Adrenaline Rush, an "energy" drink that was supposed to make them feel more alert and energetic. (The drink contained a potent brew of sugar and caffeine which, the bottle promised, would impart "superior functionality"). Some participants paid full price for the drinks, while others were offered a discount. The participants were then asked to solve a series of word puzzles. Shiv found that people who paid discounted prices consistently solved about thirty percent fewer puzzles than the people who paid full price for the drinks. The subjects were convinced that the stuff on sale was much less potent, even though all the drinks were identical. "We ran the study again and again, not sure if what we got had happened by chance or fluke," Shiv says. "But every time we ran it we got the same results."
Why did the cheaper energy drink prove less effective? According to Shiv, consumers typically suffer from a version of the placebo effect. Since we expect cheaper goods to be less effective, they generally are less effective, even if they are identical to more expensive products. This is why brand-name aspirin works better than generic aspirin, or why Coke tastes better than cheaper colas, even if most consumers can't tell the difference in blind taste tests. "We have these general beliefs about the world⎯for example, that cheaper products are of lower quality⎯and they translate into specific expectations about specific products," said Shiv. "Then, once these expectations are activated, they start to really impact our behavior.

So the next time you buy something on sale, pop a pill of L-DOPA. It will increase your pleasure, if only because you expect it to.

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Orchid Genes

Tue, 10 Nov 2009 15:28:42 -0500

David Dobbs has a fantastic new article on behavioral genetics at The Atlantic. He adds an important amendment to the vulnerability hypothesis, which holds that certain genes make people more vulnerable to psychiatric disorders. While these snippets of DNA aren't deterministic per se, when they are combined with traumatic childhood events, or a stressful few months, they can lead to serious mental illness. It's the old genes plus environment story, and it's typically cast in a negative light. But Dobbs finds that the vulnerability hypothesis comes with a positive (and often overlooked) flip-side:

At first glance, this idea, which I'll call the orchid hypothesis, may seem a simple amendment to the vulnerability hypothesis. It merely adds that environment and experience can steer a person up instead of down. Yet it's actually a completely new way to think about genetics and human behavior. Risk becomes possibility; vulnerability becomes plasticity and responsiveness. It's one of those simple ideas with big, spreading implications. Gene variants generally considered misfortunes (poor Jim, he got the "bad" gene) can instead now be understood as highly leveraged evolutionary bets, with both high risks and high potential rewards: gambles that help create a diversified-portfolio approach to survival, with selection favoring parents who happen to invest in both dandelions and orchids.
In this view, having both dandelion and orchid kids greatly raises a family's (and a species') chance of succeeding, over time and in any given environment. The behavioral diversity provided by these two different types of temperament also supplies precisely what a smart, strong species needs if it is to spread across and dominate a changing world. The many dandelions in a population provide an underlying stability. The less-numerous orchids, meanwhile, may falter in some environments but can excel in those that suit them. And even when they lead troubled early lives, some of the resulting heightened responses to adversity that can be problematic in everyday life--increased novelty-seeking, restlessness of attention, elevated risk-taking, or aggression--can prove advantageous in certain challenging situations: wars, tribal or modern; social strife of many kinds; and migrations to new environments. Together, the steady dandelions and the mercurial orchids offer an adaptive flexibility that neither can provide alone. Together, they open a path to otherwise unreachable individual and collective achievements.

This orchid hypothesis also answers a fundamental evolutionary question that the vulnerability hypothesis cannot. If variants of certain genes create mainly dysfunction and trouble, how have they survived natural selection? Genes so maladaptive should have been selected out. Yet about a quarter of all human beings carry the best-documented gene variant for depression, while more than a fifth carry the variant that Bakermans-Kranenburg studied, which is associated with externalizing, antisocial, and violent behaviors, as well as ADHD, anxiety, and depression. The vulnerability hypothesis can't account for this. The orchid hypothesis can.

This is a transformative, even startling view of human frailty and strength. For more than a decade, proponents of the vulnerability hypothesis have argued that certain gene variants underlie some of humankind's most grievous problems: despair, alienation, cruelties both petty and epic. The orchid hypothesis accepts that proposition. But it adds, tantalizingly, that these same troublesome genes play a critical role in our species' astounding success.

The orchid hypothesis--sometimes called the plasticity hypothesis, the sensitivity hypothesis, or the differential-susceptibility hypothesis--is too new to have been tested widely. Many researchers, even those in behavioral science, know little or nothing of the idea. A few--chiefly those with broad reservations about ever tying specific genes to specific behaviors--express concerns. But as more supporting evidence emerges, the most common reaction to the idea among researchers and clinicians is excitement. A growing number of psychologists, psychiatrists, child-development experts, geneticists, ethologists, and others are beginning to believe that, as Karlen Lyons-Ruth, a developmental psychologist at Harvard Medical School, puts it, "It's time to take this seriously."

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Smell and Memory

Mon, 09 Nov 2009 11:01:17 -0500

A new paper by scientists at the Weizmann Institute documents the primal connection between whiffs of smell and episodic memory. This nasal nostalgia is mediated by the hippocampus, the manufacturer of long-term memory in the brain. Here's the abstract:

Authors, poets, and scientists have been fascinated by the strength of childhood olfactory memories. Indeed, in long-term memory, the first odor-to-object association was stronger than subsequent associations of the same odor with other objects. Here we tested the hypothesis that first odor associations enjoy a privileged brain representation. Because emotion impacts memory, we further asked whether the pleasantness of an odor would influence such a representation. On day 1, we associated the same visual objects initially with one, and subsequently with a second, set of pleasant and unpleasant olfactory and auditory stimuli. One week later, we presented the same visual objects and tested odor-associative memory concurrent with functional magnetic resonance brain imaging. We found that the power (% remembered) of early associations was enhanced when they were unpleasant, regardless of whether they were olfactory or auditory. Brain imaging, however, revealed a unique hippocampal activation for early olfactory but not auditory associations, regardless of whether they were pleasant or unpleasant. Activity within the hippocampus on day 1 predicted the olfactory but not auditory associations that would be remembered one week later. These findings confirmed the hypothesis of a privileged brain representation for first olfactory associations.

As the scientists note, artists have long described the powerful linkage of smell and the past. Here's Marcel Proust, explaining the madeleine:

"When from a long distant past nothing subsists, after the people are dead, after the things are broken and scattered, taste and smell alone, more fragile but enduring, more unsubstantial, more persistent, more faithful, remain poised a long time, like souls, remembering, waiting, hoping, amid the ruins of all the rest; and bear unflinchingly, in the tiny and almost impalpable drop of their essence, the vast structure of recollection."

As I noted in Proust Was A Neuroscientist, these ornate subclauses contain some prophetic insights into how our brain works. In 1911, the year Proust began writing his novel, anatomists had no idea how our senses connected inside the skull - the brain was three pounds of mysterious mush. One of Proust's hypotheses, however, was that our senses of smell and taste bear a unique burden of memory. That's why he makes it clear that just looking at the seashell shaped cookie, which he'd glimpsed countless times in patisserie windows, brought back nothing; Combray remained lost. In fact, Proust even goes so far as to blame his sense of sight for obscuring his childhood memories in the first place. "Perhaps because I had so often seen such madelines without tasting them," Proust writes, "that their image had disassociated itself from those Combray days." Luckily for literature, Proust decided to put the cookie in his mouth. As he writes, it was "by taste and smell alone" that his childhood memories came flooding back.

Why is smell so sentimental? One possibility, which is supported by this recent experiment, is that the olfactory cortex has a direct neural link to the hippocampus. In contrast, all of our other senses (sight, touch and hearing) are first processed somewhere else - they go to the thalamus - and only then make their way to our memory center. This helps explain why we're so dependent on metaphors to describe taste and smell. We always describe foods by comparing them to something else, which we've tasted before. ("These madeleines taste just like my grandmother's madeleines!" Or: "These madeleines taste like the inside of a lemon poppy seed cake!") In contrast, we have a rich language of adjectives to describe what we see and hear, which allows us to define the sensory stimulus in lucid detail. As a result, we don't have to lean so heavily on simile and comparison.

It's also worth noting, of course, that the data doesn't quite support the strong version of the Proustian hypothesis. While olfactory associations enjoy a "privileged brain representation," that hippocampal link is less important than the unpleasantness of the smell, which is much better at predicting whether or not we'll remember the memory a few days later. This is the bleak truth of the brain: it clings to what we don't like.

For more, check out the work of Rachel Herz. And thanks to Jason Synder for the tip!

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Crying Babies

Fri, 06 Nov 2009 13:14:25 -0500

This is absolutely fascinating, yet another reminder that the structure of language infects everything. Here's Nell Greenfieldboyce, at NPR:

The distinctive sounds of a newborn's first cries may be influenced by the mother tongue of its parents.
A new study of over a thousand recorded cries from 30 French newborns and 30 German newborns found differences in the cries' melody patterns. French cries tended to have a rising melody, while the German cries tended to have a falling melody.

The finding suggests that newborns just a few days old may already be trying to imitate the prevailing intonation patterns of the language they heard while still in the womb.

The moral is that, even before we're born, we are deeply influenced by the syllables and grammars that surround us. The words are still meaningless, and yet they leave a meaningful mark on the brain. This reminds me of that great Wallace Stevens quote: "Speech is not dirty silence/Clarified. It is silence made still dirtier." Babies, it turns out, are also corrupting the silence with a kind of speech. From the moment our brain is made, we start to express ourselves in the terms and forms of language, so that even the most instinctive utterance - the scream of a newborn - is still shaped by culture.

UPDATE: Important qualifications from the always lucid Language Log:

This is a really interesting and suggestive study, which needs to be replicated to be entirely convincing. It finds a fairly large difference in the distribution of pitch and amplitude profiles of French and German neonates, with the French babies tending to produce cries with later peaks that the German babies. The effect size in the reported data is a large one (d=1.0).

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Sleep

Wed, 04 Nov 2009 17:53:19 -0500

As a chronic insomniac, I'm always a little disturbed when I learn about the lingering cognitive effects of a bad night sleep:

In a study at the Walter Reed Army Institute of Research in 2003, for example, scientists examined the cognitive effects of a week of poor sleep, followed by three days of sleeping at least eight hours a night. The scientists found that the "recovery" sleep did not fully reverse declines in performance on a test of reaction times and other psychomotor tasks, especially for subjects who had been forced to sleep only three or five hours a night.
In a similar study in 2008, scientists at the Karolinska Institute in Stockholm found that when subjects slept four hours a night over five days, and then "recovered" with eight hours a night over the following week, they still showed slight residual cognitive impairments a week later, even though they reported no sleepiness.

Or this:

In a recent study for The Archives of Internal Medicine, scientists followed 153 men and women for two weeks, keeping track of their quality and duration of sleep. Then, during a five-day period, they quarantined the subjects and exposed them to cold viruses. Those who slept an average of fewer than seven hours a night, it turned out, were three times as likely to get sick as those who averaged at least eight hours.

My problem with these studies is that they make me less likely to fall asleep. To understand why, let's play a simple game with only one rule: Don't think about white bears. You can think about anything else, but you can't think about that. Ready? Close your eyes, take a deep breath, and banish the animals from your head.

You just lost the game. Everyone loses the game. As Dostoevsky observed in Winter Notes on Summer Impressions: "Try to avoid thinking of a white bear, and you will see that the cursed thing will come to mind every minute." In fact, whenever we try not to think about something that something gets trapped in the mind, stuck in the recursive loop of self-consciousness. Our attempt at repression turns into an odd fixation.

This human frailty has profound consequences. Dan Wegner, a psychologist at Harvard, refers to the failure as an "ironic" mental process. Whenever we establish a mental goal -- such as trying not to think about white bears -- the goal is accompanied by an inevitable follow-up thought, as the brain checks to see if we're making progress. The end result, of course, is that we obsess over the one thing we're trying to avoid.

What does this have to do with sleep? For me, insomnia is my white bear. My conscious goal is to fall asleep, which then causes my unconscious to continually check up on whether or not I'm achieving my goal. And so, after passing out for thirty seconds, I'm jolted awake by my perverse brain. It's rather frustrating.

And this is why I can't help but grit my teeth when I hear about how important a good night sleep is. I know it's important, OK? I don't need more reasons to try to fall asleep, because the more I want to fall asleep - the more intensely I'm trying to achieve my goal - the less likely I am to actually pass out. I'll lie awake, haunted by thoughts of white bears and cognitive deficits.

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The Gay Animal Kingdom, Part 2

Tue, 03 Nov 2009 09:32:49 -0500

This is excellent news. Dan Delong will be back in the classroom today. I'm so relieved.

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Temptation

Tue, 03 Nov 2009 08:56:04 -0500

Why are we so dishonest? Why do we bad things, even when we know we're doing something bad? Ever since Adam and Eve ate that apple, we've assumed that there is something inherently tempting about sin. If left to our own devices, we'd all turn into men at a Vegas bachelor party, indulging in sex, drugs and slot machines. We'd loot and pillage and lie. Immorality feels good, which is why it's so hard being moral.

Some people, of course, are made of stronger stuff, which is why they stay on the righteous path. Because they're better than us, they don't eat too much cake or cheat on their taxes. (Eternal heaven is their reward for avoiding such sins.) There is good and there is bad, and being good is about resisting the allure of the bad. It's about not listening to the snake, telling us to eat the forbidden fruit.

If only morality were so easy! A new paper demonstrates, once again, that the human brain is the ultimate category buster, blurring the lines of good and bad, black and white, until everything is gray. The reason is that our behavior is deeply contextual, profoundly influenced by our surroundings and immediate situations. Whether or not we're able to resist sin, then, might depend more on the details of the sin - and whether or not it triggers our automatic urges - then on the strength of our moral fiber.

That, at least, is the tentative conclusion of a clever new fMRI study by Joshua Greene and Joe Paxton at Harvard University, who argue that sometimes we do the right thing because the wrong thing simply isn't tempting, even if it leaves us better off. Consider a hypothetical wallet, stuffed full of cash, which you find on the subway. Our moral intuitions (influenced by Genesis) tell us that everyone wants to take the money and run, that we're all attracted by the possibility of unearned cash. But this latest study suggests that, at least for the people who take the wallet to the police, there is no temptation to resist. They don't steal because they don't want to steal; telling the truth isn't hard work. They are living, in other words, in a state of moral grace, at least when it comes to the wallet. (Interestingly, Greene and Paxton found that people who behaved dishonestly in the experiment exhibited more activity in brain areas, such as the prefrontal cortex, associated with self-control. In other words, they might be trying harder to resist, but it's doing no good.) Here's Piercarlo Valdesolo, describing the study in Mind Matters:

Greene and Paxton were interested in why people behave honestly when confronted with the opportunity to anonymously cheat for personal gain. They considered two possible explanations. First, there is the "Will" hypothesis: in order to behave honestly people must actively resist the temptation to cheat. In other words, returning the wallet depends on your ability to stifle your desire to take the cash and buy yourself something nice. Alternatively, there is the "Grace" hypothesis: honest behavior results from the absence of temptation. Returning the wallet requires no particular ability to control your treacherous urges - the urge simply isn't there.
These two hypotheses make competing predictions regarding the brain regions activated when acting honestly as well as the time it should take participants to decide to act honestly. If "Will" is correct then people who choose to act honestly should exhibit heightened activity in brain regions responsible for cognitive control (presumably resulting from the struggle to ignore immediate desires). But if "Grace" is right then no such increase should occur. Furthermore, people should take a longer time to decide to act honestly if doing so requires a conscious act of "Will," but a relatively shorter time to act if all you need is a bit of "Grace."

In order to test these possibilities the researchers measured neural activity in an fMRI machine while participants played a computerized game wherein they could gain money by predicting the outcome of coin flips. Correctly guess heads or tails, you get some cash. In one condition, participants recorded their predictions before seeing any of the flips, precluding the opportunity to cheat. In the other condition, participants were rewarded based on self-reported accuracy after the flips, and therefore could fudge their predictions in accordance with the outcome of the flip. I got 100 percent correct, Mr. Experimenter, must be my lucky day!

Consistent with the "Grace" hypothesis, those who acted honestly (who guessed wrong and self-reported as much) showed no increased activity in control-related areas relative to others who guessed wrong but did not have the opportunity to cheat. Honest reporting of scores, then, didn't require will-power, these participants simply did not feel the urge to cheat. Reaction time data further supported "Grace" showing that participants who acted honestly took no longer to do so, on average, when they had the opportunity to cheat than when they did not.

Why might such a state of temporary moral grace exist? The answer returns us to evolution, and to our history as social primates. One possibility is that we come pre-programmed for certain kinds of ethical behavior, as it might be more important to have an honest reputation within the group than to have a few extra dollars. And so we return the wallet, not because we've triumphed over our sinful urges but because, at least on this one subway ride, the urge did not exist. It will be interesting to conduct some follow-up studies, and see if it's possible to induce this state of grace in strangers. How can we make people think about their social reputation, and not the cash? We're so concerned about our credit history, but what about our virtue history?

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Arts Education

Mon, 02 Nov 2009 14:05:15 -0500

Michael Posner and Brenda Patoine make a neuroscientific case for arts education. They argue that teaching kids to make art has lasting cognitive benefits:

If there were a surefire way to improve your brain, would you try it? Judging by the abundance of products, programs and pills that claim to offer "cognitive enhancement," many people are lining up for just such quick brain fixes. Recent research offers a possibility with much better, science-based support: that focused training in any of the arts--such as music, dance or theater--strengthens the brain's attention system, which in turn can improve cognition more generally.
We know that the brain has a system of neural pathways dedicated to attention. We know that training these attention networks improves general measures of intelligence. And we can be fairly sure that focusing our attention on learning and performing an art--if we practice frequently and are truly engaged--activates these same attention networks. We therefore would expect focused training in the arts to improve cognition generally.

They even have some longitudinal evidence:

In 2004, E. Glenn Schellenberg of the University of Toronto at Mississauga published results from a randomized, controlled study showing that the IQ scores of 72 children who were enrolled in a yearlong music training program increased significantly compared with 36 children who received no training and 36 children who took drama lessons. (The IQ scores of children taking drama lessons did not increase, but these children did improve more than the other groups on ratings of selected social skills.)

Just a few additional thoughts. The current obsession with measuring learning certainly has some benefits (accountability is good), but it also comes with some serious drawbacks, since it diminishes all the forms of learning, like arts education, that can't be translated into a score on a multiple choice exam. That's why the research cited above is so important: it helps us appreciate the "soft" skills that we tend to neglect.

But I think that even this clinical evaluation of arts education misses an important benefit: self-expression. I shudder to think that second graders, at least in most schools, are never taught the value of putting their mind on the page. They are drilled in spelling, phonetics and arithmetic (the NCLB school day must be so tedious), and yet nobody ever shows them how to take their thoughts and feelings and translate them into a paragraph or a painting. We assume that creativity will take care of itself, that the imagination doesn't need to be nurtured. But that's false. Creativity, like every cognitive skill, takes practice; expressing oneself well is never easy.

Finally, I think arts education, and the self-expression it encourages, can give children a tiny taste of an essential mental state: flow. First proposed by Mihály Csíkszentmihályi, flow is a condition of complete and effortless focus, characterized by total immersion in the task at hand. We don't notice the clock, or think about what we're eating for lunch - we're just thinking about what we're doing. (Not surprisingly, people are exceedingly happy while engaged in flow activities, be it composing a poem or constructing a Legos set.*)

Children have an extraordinary natural capacity for flow. (I've always loved this Auden aphorism, which he adapted from Nietzsche: "Maturity - to recover the seriousness one had as a child at play.") Unfortunately, I think most school kids never experience a taste of flow at school. Instead, they are drilled in all the usual subjects, from arithmetic to reading. The downside of this pedagogy is that it leads kids to conclude that learning is a dry and tedious pursuit, where we will always count the minutes until recess. Perhaps arts education improves our attentional system because it shows children that attention isn't always hard work. Sometimes, we want to focus, because we enjoy what we're focused on.

*I once wrote an entire essay in grad school on the presence of flow in the novels of John Updike. I think one of the reasons Updike was so interested in sex was that he saw the act of sex as a prime example of flow, a blessed state of grace in which we glimpse our larger purpose. Unfortunately, for most adults sex is their only flow experience, as work is full of meaningless drudgery.

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The Gay Animal Kingdom

Fri, 30 Oct 2009 11:04:02 -0500

I still don't have any additional details, but the initial newspaper report from the Jacksonville Journal-Courier is disturbing:

A Southwestern High School English teacher has been suspended after reports he had students in his classes to read an article about homsexuality in the animal kingdom.
Dan Delong of Carlinville acknowledged his suspension but declined to comment further until he spoke with his union representative.

Delong is said to have allowed students to read the article "The Gay Animal Kingdom" from the June 7, 2006, edition of Seed magazine. Seed magazine is a science and culture publication.

The article by Jonah Lehrer talks about the research of Joan Roughgarden, a biology professor at Stanford University who said she has documented homosexual societies among the more than 450 animal species.

School district secretary Pat Milner said a special School Board meeting has been set for 6 p.m. Monday at the district office in Piasa to discuss personnel/employee discipline.

Here, in case you're interested, is the controversial article.

UPDATE: Here's a Facebook page in support of Mr. Delong. And be sure to check out some of the comments below by his former students.

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The Neuronovel

Thu, 29 Oct 2009 13:23:51 -0500

In the latest N+1, Marco Roth takes a critical look at the rise of the "neuronovel":

The last dozen years or so have seen the emergence of a new strain within the Anglo-American novel. What has been variously referred to as the novel of consciousness or the psychological or confessional novel--the novel, at any rate, about the workings of a mind--has transformed itself into the neurological novel, wherein the mind becomes the brain. ince 1997, readers have encountered, in rough chronological order, Ian McEwan's Enduring Love (de Clérambault's syndrome, complete with an appended case history by a fictional "presiding psychiatrist" and a useful bibliography), Jonathan Lethem's Motherless Brooklyn (Tourette's syndrome), Mark Haddon's Curious Incident of the Dog in the Night-Time (autism), Richard Powers's The Echomaker (facial agnosia, Capgras syndrome), McEwan again with Saturday (Huntington's disease, as diagnosed by the neurosurgeon protagonist), Atmospheric Disturbances (Capgras syndrome again) by a medical school graduate, Rivka Galchen, and John Wray's Lowboy (paranoid schizophrenia). And these are just a selection of recently published titles in "literary fiction." There are also many recent genre novels, mostly thrillers, of amnesia, bipolar disorder, and multiple personality disorder. As young writers in Balzac walk around Paris pitching historical novels with titles like The Archer of Charles IX, in imitation of Walter Scott, today an aspiring novelist might seek his subject matter in a neglected corner or along some new frontier of neurology.

The essay is largely a lament for the decline of pre-neuroscientific novels, which weren't so infatuated with this "new reductionism of mind to brain, eagerly taken up by the press--especially the New York Times in its science pages." Here is Roth:

By comparison with most 19th-century novels, and even with most 20th-century modernist novels of the "stream of consciousness" school, the neuronovels have in them very little of society, of different classes, of individuals interacting, of development either alongside or against historical forces and expectations.

Instead, Roth argues that the new neuronovel subscribes to a cheap oversimplification of reality, in which "the proximate causes of mental function [are explained] in terms of neurochemistry, and ultimate causes in terms of evolution and heredity." The end result, Roth suggests, is "that the new genre of the neuronovel, which looks on the face of it to expand the writ of literature, appears as another sign of the novel's diminishing purview."

It's a perceptive and provocative essay, but I don't buy it. For one thing, Roth fails to place the new "neuronovel" in its proper historical context. There is nothing new or trendy about novelists borrowing the language and theories of contemporary science, or even indulging in reductionism and determinism when it suits their aesthetic principles. Consider Emile Zola, the proud founder of naturalism who aspired to write "the scientific novel." The novelist, Zola declared, must literally become a scientist, "employing the experimental method in their study of man." Unfortunately, this led Zola to proclaim his blind faith in heredity and biological determinism. As he wrote in his preface to Therese Raquin, "I have chosen people completely dominated by their nerves and blood, without free will, drawn to each action by the inexorable laws of their physical nature." Of course, Zola's theories are now woefully obsolete. As Oscar Wilde declared, "Zola sits down to give us a picture of the Second Empire. Who cares for the Second Empire now? It is out of date. Life goes faster than Realism."

The point is that the "reductionism" and "chemical determinism" that have supposedly been embraced by 21st century neuronovelists is both 1) not new and 2) far more subtle and nuanced than the reductionism and determinism celebrated by many 19th century realists. There's a long and rich history of fiction interacting with the latest scientific facts, and I think it's important to understand the neuronovel in this context. George Eliot famously described her novels as a "a set of experiments in life." (She was particularly interested in contesting the ideas of "social physics," the determinism of her day.) Virginia Woolf, before she wrote Mrs. Dalloway, said that in her new novel the "psychology should be done very realistically." Gertrude Stein did research on automatic writing with William James, before doing research in a neuroanatomy lab at Johns Hopkins. Whitman worked in Civil War hospitals and corresponded for years with the neurologist who discovered phantom limb syndrome. (He also kept up with phrenology, the brain science of his day.) Or look at Coleridge. When the poet was asked why he attended so many lectures on chemistry, he gave a great answer: "To improve my stock of metaphors". In other words, this dialogue between contemporary art and contemporary science isn't some newfangled idea, or some 21st century publishing trend designed to sell books. Rather, it's part of a distinguished attempt to grapple with the implications of scientific theory, to understand how our new facts fit with our experience.

The second problem I have with Roth's essay is his misreading of many of the neuronovels he cites. Let's begin with Saturday, Ian McEwan's 2005 retelling of Mrs. Dalloway. The protoganist of the novel is a neurosurgeon, Henry Perowne. Roth reads Saturday as a brief in favor of "stark biological determinism":

We're always in Perowne's scientific mind, a mind capable of reflecting on itself in up-to-date terms of neuroscience, though we also catch glimpses of his creator guiding us, as in the surgeon's reflections on the superiority of neuroscience to ordinary language. When Perowne drives by an antiwar demonstration, a host of half thoughts arise, on war, death, terrorism, the justness of the cause. A voice tells us that all this occurs in "the pre-verbal language that linguists call mentalese. Hardly a language, more a matrix of shifting patterns, consolidating and compressing meaning in fractions of a second. . . . Even with a poet's gift of compression, it could take hundreds of words and many minutes to describe." Of course McEwan has almost done just that, even down to the color of Perowne's thoughts--"a sickly yellow"--but only while conceding the insufficiency of his chosen medium, like a painter ruing the fact that he is not a photographer.

I'd argue that Saturday is stuffed full of ambiguity. Instead of simply embracing the one-dimensional world view of the neurosurgeon, McEwan strives to constantly complicate it. As I wrote in Proust Was A Neuroscientist:

McEwan simultaneously contests the materialist world his character inhabits. Though Henry disdains philosophy and is bored by fiction, he is constantly lost in metaphysical reveries. As he picks up fish for dinner, Henry wonders "what the chances are, of this particular fish, from that shoal, ending up in the pages, no, on this page of this copy of the Daily Mirror? Something just short of infinity to one. Similarly, the grains of sand on a beach, arranged just so. The random ordering of the world, the unimaginable odds against any particular condition." And yet, despite the odds, our reality holds itself together: the fish is there, wrapped in newspaper in the plastic bag. Existence is a miracle.
It is also a precarious miracle. Woolf showed us this with Septimus, whose madness served to highlight the fragility of sanity. McEwan chooses Baxter, a man suffering from Huntington's disease, to produce a parallel effect. Baxter's disease, thinks the neurosurgeon, "is biological determinism in its purest form. The misfortune lies within a single gene, in an excessive repeat of a single sequence--CAG." There is no escape from this minor misprint.

But McEwan doesn't make the logical mistake of believing that such a deterministic relationship is true of life in general. Henry knows that the real gift of our matter is to let us be more than matter. While operating on an exposed brain, Henry ruminates on the mystery of consciousness. He knows that even if science "solves" the brain, "The wonder will remain. That mere wet stuff can make this bright inward cinema of thought, of sight and sound and touch bound into a vivid illusion of an instantaneous present, with a self, another brightly wrought illusion, hovering like a ghost at its center. Could it ever be explained, how matter becomes conscious?"

Saturday does not answer the question. Instead, the novel strives to remind us, again and again, that the question has no answer. We will never know how the mind turns the water of our cells into the wine of consciousness. Even Baxter, a man defined by his tragic genetic flaw, is ultimately altered by a poem. When Henry's daughter begins reciting Mathew Arnold's "Dover Beach," a poem about the melancholy of materialism, Baxter is transfixed. The words "touched off a yearning he could barely begin to define." The plot of Saturday hinges on this chance event, on a mind being moved by nothing more real than rhyming words. Poetry sways matter. Could anything be less likely?

McEwan ends Saturday the way he began it: in the dark, in the present tense, with Henry in bed. It has been a long day. As Henry is drifting off to sleep, his last thoughts are not about the brain, or surgery, or materialism. All of that seems far away. Instead, Henry's thoughts return to the only reality we will ever know: our experience. The feeling of consciousness. The feeling of feeling. "There's always this, is one of his remaining thoughts. And then: there's only this."

McEwan's work is a potent demonstration that, even in this age of dizzying scientific detail, the artist remains a necessary voice. Through the medium of fiction, McEwan explores the limits of science while doing justice to its utility and eloquence. Though he never doubts our existence as a property of matter--this is why the surgeon can heal our wounds--McEwan captures the paradox of being a mind aware of itself. While we are a brain, we are the brain that contemplates its own beginnings.

Update: Be sure to check out Marco Roth's extremely smart and insightful reply in the comments below.

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