by Sam Kean
Such musings put Penfield outside the mainstream of neuroscience, but not too far outside. Historically, thinkers have always compared the brain to the technological marvels of the age: Roman doctors likened it to the aqueducts; Descartes saw a cathedral organ; scientists during the Industrial Revolution spoke of mills, looms, clocks; in the early 1900s the telephone switchboard was in vogue. Those are materialistic analogies, but neuroscience has always tolerated a fair amount of mysticism as well. Andreas Vesalius’s Fabrica provoked so much hatred in part because its precise renderings of the brain left no fuzzy places where the soul might camp out. Later generations of neuroscientists had even stronger spiritual bents. For his part, Penfield tried to split the difference: he compared the human brain to a computer, but insisted that the brain had a programmer as well—an immaterial essence that operated it.
Still, there’s no denying that neuroscientists have gotten more materialistic over the past century: the old saying that “the brain secretes thought the way the liver secretes bile” pretty much sums up their metaphysics. Penfield’s religious convictions, however, only deepened as he aged, especially as he found new spiritual outlets: at age fifty, for instance, he began laboring over a religious novel, a bildungsroman about Abraham entitled No Other Gods. Like Silas Weir Mitchell, he found he couldn’t get at some truths about the human condition except through stories. (Penfield later published a second novel, about Hippocrates, who’d studied epilepsy and the mind-body problem in ancient Greece.)
Penfield even dared to lecture here and there about how the mind arises from the brain, lectures in which he quoted Job and Proverbs and slyly promoted mind-body dualism. He got away with this because he’d built his dualism on a lifetime of surgical observations. For example, even though he could make his patients kick or bleat during surgery, he emphasized that the patients always felt they’d been forced to act. He never succeeded in activating their will to act, which proved to him that the will lay beyond the material brain. Penfield also declared that mere electricity, while able to conjure up full-blown mental scenes, could never provoke real, high-level thinking: people heard orchestras playing but never composed music themselves, or got insight into mathematical theorems. Penfield saw real thinking as something you could never trick a brain into doing because, again, the mind lay somehow beyond the brain.
However tantalizing these ideas were, Penfield could never quite alchemize them into a coherent philosophy of mind, brain, and soul. So, just before turning seventy he retired from the bustle of surgery to pursue this work full-time. He wavered month to month between optimism and despair over how much headway he’d made into the mind-body-soul problem. He never lost his faith that the soul existed, nor that some people, like temporal lobe epileptics, communed directly with God. But Penfield convinced very few colleagues to take dualism seriously, and a flippant remark he’d made when young must have haunted his later years: “When a scientist turns to philosophy,” he’d sneered, “we know he’s over the hill.”
Like Descartes and Swedenborg and so many others, Penfield never resolved the mind-body-soul paradox, and his evidence for dualism looks shakier every year. Among many other things, neuroscientists now know of brain patches that, when sparked, can indeed induce a desire to move or speak. It seems that free will is just another brain circuit. (More on this next chapter.) And while neuroscientists may not know exactly how the electrified tapioca inside our skulls gives rise to the glorious human mind, Penfield’s solution—to decide ahead of time that we have a soul, and that the soul explains everything we don’t understand about the brain—seems like a cop-out, a betrayal of the scientific ethos.
Nevertheless, unlike the vast majority of people who’ve bloviated about brains and souls, Penfield did make real, seminal contributions to neuroscience. “Brain surgery is a terrible profession,” he once wrote to his mother. “If I did not feel it would become very different in my lifetime, I should hate it.” Brain surgery did improve, not only during Penfield’s life, but because of Penfield’s life. And his innovative, unflinching approach to mapping the brain provided the first real glimpses of the ghost in the machine: the sensations and emotions—and even outright delusions—that make us human in the end.
CHAPTER NINE
“Sleights of Mind”
We’ve seen how emotions and other mental phenomena help us make decisions and form beliefs. But if those processes go awry—and they will—we fall into delusion.
To ensure everlasting peace on earth, Woodrow Wilson first had to conquer the U.S. Senate. After World War I ended, Wilson warned that civilization could not endure a second. He therefore wanted Congress to adopt the League of Nations treaty, which he saw as humanity’s last, best hope for peace. But he met realpolitik opposition in the Senate, whose members felt the treaty would sacrifice national autonomy. So in autumn 1919 President Wilson took his case to the American people, embarking on an eight-thousand-mile, twenty-two-day speaking tour to stir up anger and break his opponents. The tour broke Wilson instead.
After stop number one, Seattle, Wilson and his entourage chugged down the Pacific coast, then circled east toward the Rockies. Already feeling weak, Wilson was clobbered by altitude sickness near Denver, and he stumbled getting onstage in Pueblo on September 25, thanks to a piercing headache. He nevertheless boarded a train for Wichita that afternoon. Just twenty miles down the track he fell ill, and his doctor suggested they halt the train and take a walk along a dirt road. On the stroll Wilson met a farmer who gave him a cabbage and apples, then hopped a fence to chat up a wounded private on a porch. He returned to the train refreshed. But at 2 a.m. he knocked on the door of his wife, Edith’s, sleeping car, complaining of another staggering headache. More ominously, Wilson’s physician, Cary Grayson, noticed that half, and only half, of the president’s face had started twitching.
Grayson was already treating Wilson for various ailments—high blood pressure, intermittent migraines, intestinal distress (which Wilson referred to as “turmoil in Central America”). In retrospect, Wilson had probably also suffered two miniature strokes, in 1896 and 1906; Silas Weir Mitchell himself had examined the president-elect in 1912 and declared that Wilson wouldn’t survive his first term. Year by year after that, Grayson had watched Wilson grow increasingly brittle. He’d even begged Wilson to skip the speaking tour in 1919—a proposal that Wilson had raged at, considering it insubordination. Now, outside Wichita, Grayson ordered the train to stop and suggested that Wilson cancel his remaining speeches. Uncharacteristically, the president relented, too weak to fight. Wilson spent much of the thirty-six-hour ride home staring out the window and occasionally weeping, the left half of his face sagging lower every hour.
Back in Washington a cruel cranial pain prevented Wilson from working, and he spent his days playing pool, riding in touring cars, and watching silent films in the White House cinema. Meanwhile, the League of Nations treaty stalled in the Senate. Wilson’s nemesis, Senator Henry Cabot Lodge, even started mocking the literary quality of the League’s grandiloquent charter, a charter penned by Wilson himself.
At 8:30 a.m. on October 2, Edith checked in on Wilson and found him awake in bed, weak and complaining of numbness. She made a crutch of herself beneath his shoulder, dragged him to the toilet, and left to summon Grayson. She returned to find Wilson crumpled on the floor, half naked and unconscious. She and Grayson immediately closed off Wilson’s bedroom to all visitors, but a White House usher peeked in later and saw Wilson laid out like a waxwork, looking entirely dead except for the raw red gashes on his nose and temple, where he’d struck the exposed bathtub plumbing after collapsing.
For the next few months servants had to prop Wilson in a wheelchair each morning and hand-feed him. This latest stroke had paralyzed his left side, and he spent most days listening to Edith read or zoning out in the garden. Washington meanwhile lumbered along without him, because very few people knew about the stroke at first—it certainly wasn’t public knowledge. In March 1915
Grayson had introduced Edith to the recently widowed Wilson, and Edith quid pro quoed by insisting that Wilson promote Grayson, a navy man, to rear admiral over dozens of better-qualified candidates. Now the two old chums conspired to conceal Wilson’s health from most of his cabinet members and even the vice president—a constitutionally dicey situation. Before 1919 five presidents had died in office, most of them quickly; only Garfield had lingered, and he’d remained lucid. Not Wilson. In late November a press secretary painted a haunting image of Wilson as “a broken, ruined old man, shuffling along, his left arm inert, the fingers drawn up like a claw, the left side of his face sagging frightfully. His voice is not human; it gurgles in his throat, sounds like that of an automaton.” In the vacuum of power* Edith essentially became the first female president, controlling what papers Wilson saw and sending out memos in his name but her handwriting.
Wilson resumed his duties as president after a few months, but he continued to struggle. He limped along with a cane, and photographers avoided shooting the melted left half of his face. Neurologically, he was, if anything, worse. Already an icy man, he grew even colder and more imperious, a sign of mental inflexibility. At the same time he was prone to weeping, a sign of emotional instability. Strangest of all, he stopped noticing things to his left. This wasn’t eye trouble, since Wilson could, technically, see things on his port side: he didn’t bump into furniture over there, for instance, since his unconscious brain could steer him around it. But he didn’t consciously notice things on his left side unless someone pointed them out. As a hypothetical example, a dozen fountain pens could be piled on the left-hand side of his desk, but unless there was also one on the right-hand side, he’d complain about not having a pen at hand—as if the whole left side of his world didn’t count. Bewildered aides had to rearrange his office, and they learned to usher guests in on his right side or else he’d snub them.
Eventually Wilson’s intransigence doomed the League. He rebuffed all suggestions that he amend its charter—it was peace the Wilson way, or go to hell—and the ratification movement languished. Convinced he could nevertheless ram the League through Congress later, Wilson began campaigning for a third presidential term in 1920, even though he’d become a veritable recluse. Edith, Grayson, and others mercifully sabotaged this campaign at the Democratic National Convention in San Francisco that year by spreading rumors—actually the truth—about Wilson’s impairments. The next year Wilson left the White House in tears, and even in his dotage remained convinced that he’d lost not one ounce of mental vigor. As late as January 1924 he sat down at his desk and sketched out a third inaugural address. He died within two weeks, his damaged brain finally exhausting itself.
Fifty years later, in a separate but equal branch of government, a Supreme Court justice reprised Wilson’s sad farce. By 1974 William O. Douglas had become the longest-serving justice in Court history, having been appointed by FDR in 1939. He’d also become a globetrotting liberal rabble-rouser and a pariah to conservatives: while Speaker of the House, Gerald Ford had tried to impeach him. On December 31, 1974, Douglas touched down in the Bahamas to celebrate the New Year there, accompanied by his fourth wife, a thirty-one-year-old blonde not even born when he’d joined the Court. Within hours of landing, Douglas had a stroke and collapsed.
Airlifted out of Nassau, he arrived at Walter Reed Hospital in Washington and spent the next few months convalescing. In all he missed twenty-one Supreme Court votes, and although his doctors noticed little progress—Douglas couldn’t walk and his left side remained paralyzed—he refused to resign from the Court. Finally, in March, he badgered one doctor into granting him an overnight pass to visit his wife. Instead of heading home, though, Douglas instructed his driver (he certainly couldn’t drive himself) to visit his office. He began catching up that very night and never returned to the hospital.
Douglas had some good reasons not to resign. His old enemy Gerald Ford had become president, and Douglas feared that Ford would “appoint some bastard” to take his place. Plus, the court would hear important cases that term on campaign finance and the death penalty. But mostly Douglas refused to resign because in his own mind there was nothing wrong. At first he told reporters that, far from having had a stroke, he’d merely stumbled, Gerry Ford–like, and gotten a little banged up—never mind the slurred speech and the wheelchair. When questioned about this, he claimed that the stories circulating about his paralysis were rumors, and he challenged naysayers to go hiking with him. When pressed further, he swore that he’d been kicking forty-yard field goals with his paralyzed leg that very morning. Hell, he said, his doctor wanted him to try out for the Redskins.
If anything, Douglas’s performance away from reporters was more pathetic still. He started sleeping through hearings, forgetting names, confusing facts on important cases, and whispering to aides about assassins; because of chronic incontinence, his secretary had to drench his wheelchair in Lysol. The other eight justices, although bound by omertà not to pressure Douglas publicly, agreed to table all 4–4 ties until the next term and not let Douglas cast deciding votes. In a small concession to reality Douglas did seek specialized stroke treatment in New York during the summer recess in 1975, but he failed to improve. The other justices finally forced Douglas to resign in November—and even then Douglas kept returning to work, calling himself the “Tenth Justice,” commandeering clerks, and attempting to cast more votes. Nothing’s wrong with me, he insisted. It was a bewildering end for an eminent jurist.
Cases like Wilson’s and Douglas’s—both the result of parietal lobe damage—are depressingly familiar to neurologists. Wilson had hemispatial neglect, the inability to notice half the world. Neglect patients shave only half their faces and dress only half their bodies. Ask them to copy a simple line drawing of a flower, and they’ll bisect the daisy. Give them a bowl of salad, and they’ll eat just half of it. Rotate the salad ninety degrees, and they’ll eat just half the remainder. Their memories are bisected, too. Italian neuroscientists once asked a few hemispatial neglect victims to imagine standing in the famous square in their hometown, Milan, while facing the cathedral. When asked to name every building around the square, victims could remember the structures only on one side. The scientists then asked them to turn around mentally and face the opposite direction. At this point they could name all the buildings on the other side—but not a single one of those they’d named seconds before. Even blatant contradictions of logic and sense cannot penetrate hemispatial neglect. One man who neglected everything to his left got confused about how to draw 11:10 on a clock face. He finally drew the numerals six through twelve going up the wrong side—forcing the clock to tick counterclockwise. The paradox didn’t distress him, though. Unlike regular stroke victims, who often lament their disabilities and grow depressed, people with hemispatial neglect usually remain blithe and cheerful.
On the right half of the quadrant, drawings by a man who suffers from hemispatial neglect; he cannot notice anything to his left. (Masud Husain, from “Hemispatial Neglect,” Parton, Malhotra, and Husain, Journal of Neurology, Neurosurgery, and Psychiatry 75, no. 1 [2004]: 13–21)
Along those same lines, some stroke victims, like Douglas, refuse to admit they’re paralyzed, and they lie shamelessly to themselves and others to maintain a delusion of competence. (Doctors call these patients anosognosics, from the term “anosognosia”—literally, an inability to recognize illness.) Ask them to raise their paralyzed arm, and they’ll grin and claim it’s tired, or say, “I’ve never been ambidextrous.” Ask them to lift a tray full of cocktail glasses and—unlike normal hemiplegics, who grab the tray’s middle with their one good arm—they’ll grab the tray at one end, as if their other arm is there to help support it. When they (inevitably) flip the whole works over, they’ll make up excuses. One anosognosic woman, when asked to clap, raised her one functioning arm and swished it in the air in front of her. (To which her doctor naughtily replied that she’d finally solved the old Zen koan: here was the sound
of one hand clapping.) The really strange thing is how normal anosognosics seem otherwise. They can make jokes, reminisce about old times, and speak fluently. But their judgment has been warped, and on one topic especially—their disability—they’re daft. A few stroke patients, after being stricken blind, deny even this deficit, to the detriment of their shins and the distress of anyone watching them cross the street.
We’ve learned a lot about the brain’s hardware so far. Learned how neurons work and how they wire themselves together into circuits. Learned how webs of interlocking circuits create vision and movement and emotion. But it’s time to cross over from the physical to the mental—and there’s no better bridge for this than delusions. Doctors have dealt with delusions for millennia, of course, and have long known certain psychological facts: that many delusions disappear after a few weeks, and that some appear most commonly among certain personality types, such as perfectionists. But only in the past century have doctors seen enough cases, with enough eerily similar symptoms, to determine that many delusions have an organic basis in the brain. In fact, some delusions are so reproducible, and knock out such specific mental modules, that they’ve become a spectacular tool for probing one of the great mysteries of neuroscience: how cells and biochemicals give rise to the human mind, in all its oddness.
