The Violinist's Thumb: And Other Lost Tales of Love, War, and Genius, as Written by Our Genetic Code (31 page)

The best-known runt today is probably the “hobbit” skeleton from the Indonesian island of Flores. When it was discovered in 2003, many scientists declared it a stunted or microcephalic (tiny-headed) human; no way evolution was irresponsible enough to let the brains of a hominid dwindle that much, brains being about all we hominids have going. But nowadays most scientists accept that the brains of hobbits (officially,
Homo floresiensis
) did shrink. Some of this diminution might relate to so-called island dwarfism: islands, being severely finite, have less food, so if an animal can tune down some of the hundreds of genes that control its height and size, it can get by with fewer calories. Island dwarfism has shrunk mammoths, hippos, and other stranded species to pygmy sizes, and there’s no reason to think this pressure wouldn’t squash a hominid, even if the cost is a punier brain.
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By some measures, modern humans are runts, too. We’ve probably all gone to a museum and snickered over the wee suit of armor that a king of England or some other big swinging dick from history wore—what a shrimp! But our ancestors would
giggle at our clothes just the same. Since about 30,000 BC, our DNA has diminished the average human body size by 10 percent (roughly five inches). The vaunted human brain dwindled by at least 10 percent over that span, too, and a few scientists argue it has shrunk even more.

Scientists filling skulls with buckshot or millet in the early 1900s didn’t know about DNA, of course, but even with their crude tools, they could tell the brain size–intelligence theory didn’t add up. One famous study of geniuses—it got a two-page spread in the
New York Times
in 1912—did find some truly capacious organs. Russian writer Ivan Turgenev’s brain topped seventy ounces, compared to a human average of fifty. At the same time, the brains of statesman Daniel Webster and mathematician Charles Babbage, who dreamed up the first programmable computer, were merely average. And poor Walt Whitman had to sound his barbaric yawp over the rooftops with a command center of just forty-four ounces. Even worse was Franz Joseph Gall. Though an intelligent scientist—he proposed for the first time that different brain regions have different functions—Gall also founded phrenology, the analysis of head lumps. To his followers’ eternal shame, he weighed in at a measly forty-two ounces.

To be fair, a technician dropped Whitman’s brain before measuring it. It crumbled into pieces like a dried-out cake, and it’s not clear whether they found all of them, so maybe Walt could have made a better showing. (No such mishap with Gall.) Regardless, by the 1950s the size-smarts theory had received some fatal wounds, and any lingering association between brain heft and braininess died for good a few hours after Albert Einstein himself died in 1955.

After suffering an aortic aneurysm on April 13, 1955, Einstein found himself the subject of an international death watch. He
finally succumbed to internal hemorrhaging at 1:15 a.m. on April 18. His body arrived shortly thereafter at a local hospital in Princeton, New Jersey, for a routine autopsy. At this point the pathologist on duty, Thomas Harvey, faced a stark choice.

Any one of us might have been tempted the same way—who wouldn’t want to know what made Einstein
Einstein?
Einstein himself expressed interest in having his brain studied after he died, and even sat for brain scans. He decided against preserving the best part of himself only because he loathed the thought of people venerating it, the twentieth-century equivalent of a medieval Catholic relic. But as Harvey arranged the scalpels in his autopsy room that night, he knew humankind had just one chance to salvage the gray matter of the greatest scientific thinker in centuries. And while it may be too strong to say
stole,
by 8 a.m. the next morning—without next-of-kin permission, and against Einstein’s notarized wish for cremation—Harvey had shall we say
liberated
the physicist’s brain and released the body to the family without it.

The disappointment started immediately. Einstein’s brain weighed forty-three ounces, at the low end of normal. And before Harvey could measure anything more, word of the relic spread, just as Einstein had feared. During a discussion in school the next day about the loss of Einstein, Harvey’s son, normally a laconic lad, blurted out, “My dad’s got his brain!” A day later, newspapers across the country mentioned Harvey’s plans in their front-page obits. Harvey did eventually convince the remaining Einsteins, who were sure peeved, to grant permission for further study. So after measuring its dimensions with calipers and photographing it for posterity with his 35 mm black-and-white camera, Harvey sawed the brain into 240 taffy-sized hunks and lacquered each one in celloidin. Harvey was soon mailing the blobs in mayo jars to neurologists, confident that the forthcoming scientific insights would justify his peccadillo.

Fragments of Einstein’s brain, shellacked in hard celloidin after the physicist’s death in 1955. (Getty Images)

This certainly wasn’t the first autopsy of a famous person to take a lurid turn. Doctors set aside Beethoven’s ear bones in 1827 to study his deafness, but a medical orderly nicked them. The Soviet Union founded an entire institute in part to study Lenin’s brain and determine what makes a revolutionary a revolutionary. (The brains of Stalin and Tchaikovsky also merited preservation.) Similarly, and despite the body being mutilated by mobs, Americans helped themselves to half of Mussolini’s brain after World War II, to determine what made a dictator a dictator. That same year the U.S. military seized four thousand pieces of human flesh from Japanese coroners to study nuclear radiation
damage. The spoils included hearts, slabs of liver and brain, even disembodied eyeballs, all of which doctors stored in jars in radiation-proof vaults in Washington, D.C., at a cost to taxpayers of $60,000 per year. (The U.S. repatriated the remains in 1973.)

Even more grotesquely, William Buckland—in a story that’s possibly apocryphal, but that his contemporaries believed—topped his career as a gourmand when a friend opened a silver snuffbox to show off a desiccated morsel of Louis XIV’s heart. “I have eaten many strange things, but have never eaten the heart of a king,” Buckland mused. Before anyone thought to stop him, Buckland wolfed it down. One of the all-time raciest stolen body parts was the most private part of Cuvier’s patron, Napoleon. A spiteful doctor lopped off L’Empereur’s penis during the autopsy in 1821, and a crooked priest smuggled it to Europe. A century later, in 1927, the unit went on sale in New York, where one observer compared it to a “maltreated strip of buckskin shoelace.” It had shriveled to one and one-half inches, but a urologist in New Jersey bought it anyway for $2,900. And we can’t wrap up this creepy catalog without noting that yet another New Jersey doctor disgracefully whisked away Einstein’s eyeballs in 1955. The doctor later refused Michael Jackson’s offer to pay millions for them—partly because the doc had grown fond of gazing into them. As for the rest of Einstein’s body, take heart (sorry). It was cremated, and no one knows where in Princeton his family scattered the ashes.
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Perhaps the most disheartening thing about the whole Einstein fiasco is the paltry knowledge scientists gained. Neurologists ended up publishing only three papers on Einstein’s brain in forty years, because most found nothing extraordinary there. Harvey kept soliciting scientists to take another look, but after the initial null results came back, the brain chunks mostly just sat around. Harvey kept each section wrapped in cheesecloth and piled them into two wide-mouthed glass cookie jars full of
formaldehyde broth. The jars themselves sat in a cardboard box labeled “Costa Cider” in Harvey’s office, tucked behind a red beer cooler. When Harvey lost his job later and took off for greener pastures in Kansas (where he moved in next door to author and junkie William S. Burroughs), the brain rode shotgun in his car.

In the past fifteen years, though, Harvey’s persistence has been justified, a little. A few cautious papers have highlighted some atypical aspects of Einstein’s brain, on both microscopic and macroscopic levels. Coupled with loads of research into the genetics of brain growth, these findings may yet provide some insight into what separates a human brain from an animal brain, and what pushes an Einstein a few standard deviations beyond that.

First, the obsession with overall brain size has given way to obsessing over the size of certain brain parts. Primates have particularly beefy neuron shafts (called axons) compared to other animals and can therefore send information through each neuron more quickly. Even more important is the thickness of the cortex, the outermost brain layer, which promotes thinking and dreaming and other flowery pursuits. Scientists know that certain genes are crucial for growing a thick cortex, partly because it’s so sadly obvious when these genes fail: people end up with primitively tiny brains. One such gene is
aspm.
Primates have extra stretches of DNA in
aspm
compared to other mammals, and this DNA codes for extra strings of amino acids that bulk up the cortex. (These strings usually start with the amino acids isoleucine and glutamine. In the alphabetic abbreviations that biochemists use for amino acids, glutamine is usually shortened to
Q
[
G
was taken] and isoleucine to plain
I
—which means we probably got an intelligence boost from a string of DNA referred to, coincidentally, as the “IQ domain.”)

In tandem with increasing cortex size,
aspm
helps direct a process that increases the density of neurons in the cortex,
another trait that correlates strongly with intelligence. This increase in density happens during our earliest days, when we have loads of stem cells, undeclared cells that can choose any path and become any type of cell. When stem cells begin dividing in the incipient brain, they can either produce more stem cells, or they can settle down, get a job, and become mature neurons. Neurons are good, obviously, but each time a neuron forms, the production of new stem cells (which can make additional neurons in the future) stops. So getting a big brain requires building up the base population of stem cells first. And the key to doing that is making sure that stem cells divide evenly: if the cellular guts get divided equally between both daughter cells, each one becomes another stem cell. If the split is unequal, neurons form prematurely.

To facilitate an even split,
aspm
guides the “spindles” that attach to chromosomes and pull them apart in a nice, clean, symmetrical way. If
aspm
fails, the split is uneven, neurons form too soon, and the child is cheated of a normal brain. To be sure,
aspm
isn’t
the
gene responsible for big brains: cell division requires intricate coordination among many genes, with master regulator genes conducting everything from above, too. But
aspm
can certainly pack the cortex with neurons
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when it’s firing right—or sabotage neuron production if it misfires.

Einstein’s cortex had a few unusual features. One study found that, compared to normal elderly men, his had the same number of neurons and the same average neuron size. However, part of Einstein’s cortex, the prefrontal cortex, was thinner, which gave him a greater density of neurons. Closely packed neurons may help the brain process information more quickly—a tantalizing find considering that the prefrontal cortex orchestrates thoughts throughout the brain and helps solve multistep problems.

Further studies examined certain folds and grooves in Einstein’s cortex. As with brain size, it’s a myth that simply having
more folds automatically makes a brain more potent. But folding does generally indicate higher functioning. Smaller and dumber monkeys, for instance, have fewer corrugations in their cortexes. As, interestingly, do newborn humans. Which means that as we mature from infants to young adults, and as genes that wrinkle our brains start kicking on, every one of us relives millions of years of human evolution. Scientists also know that a lack of brain folds is devastating. The genetic disorder “smooth brain” leaves babies severely retarded, if they even survive to term. Instead of being succulently furrowed, a smooth brain looks eerily polished, and cross sections of it, instead of showing scrunched-up brain fabric, look like slabs of liver.