Brain Trust (9 page)

Is this because imagining eating makes you feel full?

To test this, Morewedge had subjects imagine eating either M&M’s or cheese, and then offered them a cheese bowl. Only the subjects who imagined eating cheese ate fewer squares. So it’s not a phantom feeling of fullness that keeps you from overindulging, it’s that—as opposed to just cuing the food, which sensitizes you to it—imagining eating a food habituates you to it. One piece of cake is great, two is good, three is OK, but four is bad. And imagining you’ve already had a couple slices means that when you actually start eating, you’re further into the downward trajectory of enjoyment.

“But the effect is undone when you’re exposed to a different stimulus,” says Morewedge. So if you’re going to be tempted by potato chips you have to imagine chips. If it’s ice-cream-and-movie night, you have to specifically imagine eating ice cream. If you go down the list of goodies at an upcoming Thanksgiving meal, when you imagine eating yams, you will overwrite the inoculation of having previously imagined eating stuffing.

But if you can predict a tempting food, imagine eating it—the more the better. Then when it’s there in front of you, you’ll eat less.

Speaking of the health benefits of the mind
, a study at Harvard Medical School found that even when patients were explicitly told the drugs they were taking were placebos, devoid of active ingredients (in fact, the pill bottles were labeled placebo), their health improvements far outstripped peers given no sugar pills. While more research is needed, the study’s authors suggest that the “medical ritual” of taking pills—any pills—might be to blame.

Believe it or not, Hugh Herr is this book’s lone representative of the Sports Hall of Fame. A prodigy rock climber, Herr lost both lower legs to frostbite, the result of three nights in -20°F temps stranded in a blizzard on Mt. Washington. After rehab, Herr built prosthetic feet and hopped back on the rock, not in an I-still-want-to-climb-even-though-I-really-can’t kind of way, but with the intent of picking up where he left off—on a tear through the country’s hardest climbs. He showed up at the steep granite cliffs of Index, Washington, with tiny wedges of rubber-covered steel attached to metal tubing, which he planned to use as “feet” on the notorious overhanging crack City Park, which despite a bevy of able-bodied suitors had previously seen only one ascent.

Three days later, Herr styled it. And he did so partly because his prosthetic feet let him do something that ordinary climbers couldn’t—wedge his “toes” into the viciously thin crack in order to take weight off his arms.

Not only had his prosthetics allowed him to perform as well as other humans, they made him superhuman. And it’s this lack of human-as-end-goal approach that Herr brings to his work at MIT. “About half the work we do is augmentative,” says Herr, meaning that while he’s designed some of the world’s best replacement legs and feet, he also designs mechanics to be worn on healthy humans. These are the exoskeletons that futurists and sci-fi buffs have imagined at least since 1963 when the character Iron Man debuted in
Tales of Suspense
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. Imagine being able to run for miles with a hundred-pound backpack or jump from a two-story building. Herr’s exoskeletons will make both possible.

But even more awesome is a project that brings Herr’s interests
full circle. “We’re in the process of building a spider suit that augments the human ability to climb,” says Herr. Basically, the suit will be a soft and flexible second skin jacket, with strong latex webs at the joints. These webs hold the suit and thus the arms, hands, and fingers in a fully flexed position—as at the apex of a pull-up. “It’s cool ’cause there’s no power source,” says Herr. Instead, the suit makes use of muscle power that’s generally unused while climbing—your pushing muscles. To extend your arms above your head, you push to stretch these latex webs, and when you pull down, the bands contract to pull with you. “The bicycle was invented, and now we have the sport of cycling,” says Herr, “and just like that, someday we’ll have a new sport of power climbing or augmented running. Augmentative technology will allow humans to do things we haven’t even imagined yet.”

If you want a preview, as I most certainly did, try the following: Connect short lengths of surgical tubing from both shoulders to both hands so that you can only raise your arms with effort. Then stretch strong rubber bands from each fingernail to the base of each finger, as shown on
this page
. The tricky part is keeping the bands in place, which I did with the liberal application of Super Glue (in the name of science!). Though only a rough prototype and admittedly pretty cumbersome, the bands made me immediately able to chuck mad dynos (translation: pull from hold to hold, not lob angry diplodocuses) at the climbing gym.

I’m sure that at least the gathered muscle-bound, knuckle-dragging college students thought it was pretty awesome.

On display at the Museum of Natural History
is a 4’ x 11’ swatch of 96-thread-count spider silk cloth—as strong as steel and much tougher. It represents the contribution of more than one million female golden orb spiders, which were milked by hand in Madagascar. That’s the problem with spider silk—spiders don’t spin cocoons and they eat only live food, and so farming them for silk is nearly impossible. Which is why it’s especially exciting that scientists from Notre Dame and the University of Wyoming have inserted spider genes into silkworms. Already the worms are producing stronger, softer fabric than any previous silkworms. In addition to textile applications (including bulletproof vests), researchers hope their new hybrid silk will someday replace cadaver-derived artificial tendons.

“It’s like you need × amount of good feeling in the course of existence and you can get it in different ways,” says Mark Wilson, psychobiologist at Emory University and Yerkes National Primate Research Center. One way monkeys in his lab get this good feeling is through dominance in the social hierarchy. It feels good to be top rhesus.

But there’s another way.

Wilson gave his monkeys banana-flavored pellets, much richer in sugars than their normal diet. As you’d expect, all monkeys liked the banana pellets—I mean, who wouldn’t? But check this out: Monkeys at the top of the social hierarchy regulated banana pellets to keep their caloric intake roughly similar to that of their standard diet.

Subordinate monkeys didn’t. They binged.

Specifically, while the dominant monkeys might opportunistically snack on pellets during the day, subordinate monkeys stayed up late into the night, stuffing their faces with sugary goodness. (Midnight ice cream, anyone?)

The explanation Wilson favors is that a sugary diet excites dopamine pathways in the brain. Dominant monkeys already get their dopamine fix from social interactions, while subordinate monkeys get none. So we’re back to “X amount of a good feeling”—subordinate monkeys eat their way to the dopamine release that dominant monkeys get naturally.

Going human, Wilson posits that, “If you’re much less than X, you’re much more prone to addictions of all sorts—food, exercise, shopping, gambling, psychostimulants.”

It’s easy to see how this applies to something like diet. “It’s the notion my grandmother talked to me about,” says Wilson,
“comfort food.” The trick in losing weight is to find comfort another way—without the food. Simply, if you make your life happier, you’ll be less driven to overeat.

A survey of 30,816 Europeans found that
Danes are happiest and Bulgarians the least happy. Factors most responsible for happiness were younger age, satisfaction with household income, being employed, high community trust, and religious conviction. However, an unrelated study found that while short-term happiness rises and falls with a country’s economy, long-term happiness has nothing to do with your country’s wealth.

Ted Williams entered the final two games of the 1941 season batting .39955. If he’d sat them out, the average would’ve been rounded up to .400, making him the first (and still the only) MLB player to bat the milestone. Manager Joe Cronin told Williams the decision to play and risk it or simply sit on the record was up to Williams, who famously said, “If I can’t hit .400 all the way, I don’t deserve it.” He went six for eight in the season-ending double-header and finished with a .406 batting average.

“But many players make the other choice,” says Devin Pope, behavioral scientist at the University of Chicago’s Booth School of Business. Though no one’s yet had the good fortune to confront the decision while camped at .400, many players have entered
their last at bat with a .300 average. “More than 30 percent of those batters send in a pinch hitter,” says Pope. On the flip side of the .300 fence, Pope explains that batters at .299 never send in pinch hitters—and they never walk. For better or for worse, players who go into their final at-bat with a .299 average swing, trying to get the hit that puts them over the .300 hump.

The same is true of the diamond market. “You can’t find any .99-carat diamonds,” says Pope. Dealers know their customers will pay significantly more for a 1-carat diamond than they would for a .99-carat one, and so cut the stones accordingly.

So too with SAT scores. If a student scores xx90—like 1,590 or 1,690—they’re about 20 percent more likely to retake the test than someone who scored lower in the last two digits. Next time—certainly—they’ll hit that next hundred-point marker!

Thanks to our irrational human brains, we value these milestones—a .300 hitter, a 1-carat diamond, an 1,800 SAT score—disproportionately more than if they were just a tick lower. This means that batters have incentive to ride the pine at .300 or swing for a single at .299, trying to get to the high side of a value fence and thus likely earn a higher salary after the next contract negotiation. Conversely, advertisers exploit the low side of the value fence, pricing a gallon of milk at $3.99 and a car at $19,995. To our brains, the savings looks much larger than it actually is.

This also means that every time your car’s odometer gains a digit in the hundreds spot, it loses twenty dollars in resale value. Devin Pope showed that a car with 50,799 miles is worth twenty dollars more than a car with 50,800 miles. That’s an expensive mile. But a car with 50,899 miles is still worth as much as it was at 50,800. In respect to miles, your car doesn’t lose value smoothly—it ratchets downward with the hundreds digit.