“Oh, let’s see, fifty-nine or sixty?” Eugene replied. He was seventy-one years old.
The scientist started typing on the computer. Eugene smiled and pointed at it. “That is really something,” he said. “You know, when I was in electronics there would have been a couple of six-foot racks holding that thing!”
The scientist was fifty-two-year-old Larry Squire, a professor who had spent the past three decades studying the neuroanatomy of memory. His specialty was exploring how the brain stores events. His work with Eugene, however, would soon open a new world to him and hundreds of other researchers who have reshaped our understanding of how habits function. Squire’s studies would show that even someone who can’t remember his own age or almost anything else can develop habits that seem inconceivably complex-until you realize that everyone relies on similar neurological processes every day. His and others’ research would help reveal the subconscious mechanisms that impact the countless choices that seem as if they’re the products of well-reasoned thought, but actually are influenced by urges most of us barely recognize or understand.
By the time Squire met Eugene, he had already been studying images of his brain for weeks. The scans indicated that almost all the damage within Eugene’s skull was limited to a five-centimeter area near the center of his head. The virus had almost entirely destroyed his medial temporal lobe, a sliver of cells which scientists suspected was responsible for all sorts of cognitive tasks such as recall of the past and the regulation of some emotions. The completeness of the destruction didn’t surprise Squire-viral encephalitis consumes tissue with a ruthless, almost surgical, precision. What shocked him was how familiar the images seemed.
Thirty years earlier, as a PhD student at MIT, Squire had worked alongside a group studying a man known as “H.M.,” one of the most famous patients in medical history. When H.M.-his real name was Henry Molaison, but scientists shrouded his identity throughout his life-was seven years old, he was hit by a bicycle and landed hard on his head. [8] [9] [10] Soon afterward, he developed seizures and started blacking out. At sixteen, he had his first grand mal seizure, the kind that affects the entire brain; soon, he was losing consciousness up to ten times a day.
By the time he turned twenty-seven, H.M. was desperate. Anticonvulsive drugs hadn’t helped. He was smart, but couldn’t hold a job. [11] He still lived with his parents. H.M. wanted a normal existence. So he sought help from a physician whose tolerance for experimentation outweighed his fear of malpractice. Studies had suggested that an area of the brain called the hippocampus might play a role in seizures. When the doctor proposed cutting into H.M.’s head, lifting up the front portion of his brain, and, with a small straw, sucking out the hippocampus and some surrounding tissue from the interior of his skull, H.M. [12] [13] gave his consent.
The surgery occurred in 1953, and as H.M. healed, his seizures slowed. Almost immediately, however, it became clear that his brain had been radically altered. H.M. knew his name and that his mother was from Ireland. He could remember the 1929 stock market crash and news reports about the invasion of Normandy. But almost everything that came afterward-all the memories, experiences, and struggles from most of the decade before his surgery-had been erased. When a doctor began testing H.M.’s memory by showing him playing cards and lists of numbers, he discovered that H.M. couldn’t retain any new information for more than twenty seconds or so.
From the day of his surgery until his death in 2008, every person H.M. met, every song he heard, every room he entered, was a completely fresh experience. His brain was frozen in time. Each day, he was befuddled by the fact that someone could change the television channel by pointing a black rectangle of plastic at the screen. He introduced himself to his doctors and nurses over and over, dozens of times each day. [14]
“I loved learning about H.M., because memory seemed like such a tangible, exciting way to study the brain,” Squire told me. “I grew up in Ohio, and I can remember, in first grade, my teacher handing everyone crayons, and I started mixing all the colors together to see if it would make black. Why have I kept that memory, but I can’t remember what my teacher looked like? Why does my brain decide that one memory is more important than another?”
When Squire received the images of Eugene’s brain, he marveled at how similar it seemed to H.M.’s. There were empty, walnut-sized chunks in the middle of both their heads. Eugene’s memory-just like H.M.’s-had been removed.
As Squire began examining Eugene, though, he saw that this patient was different from H.M. in some profound ways. Whereas almost everyone knew within minutes of meeting H.M. that something was amiss, Eugene could carry on conversations and perform tasks that wouldn’t alert a casual observer that anything was wrong. The effects of H.M.’s surgery had been so debilitating that he was institutionalized for the remainder of his life. Eugene, on the other hand, lived at home with his wife. H.M. couldn’t really carry on conversations. Eugene, in contrast, had an amazing knack for guiding almost any discussion to a topic he was comfortable talking about at length, such as satellites-he had worked as a technician for an aerospace company-or the weather.
Squire started his exam of Eugene by asking him about his youth. Eugene talked about the town where he had grown up in central California, his time in the merchant marines, a trip he had taken to Australia as a young man. He could remember most of the events in his life that had occurred prior to about 1960. When Squire asked about later decades, Eugene politely changed the topic and said he had trouble recollecting some recent events.
Squire conducted a few intelligence tests and found that Eugene’s intellect was still sharp for a man who couldn’t remember the last three decades. What’s more, Eugene still had all the habits he had formed in his youth, so whenever Squire gave him a cup of water or complimented him on a particularly detailed answer, Eugene would thank him and offer a compliment in return. Whenever someone entered the room, Eugene would introduce himself and ask about their day.
But when Squire asked Eugene to memorize a string of numbers or describe the hallway outside the laboratory’s door, the doctor found his patient couldn’t retain any new information for more than a minute or so. When someone showed Eugene photos of his grandchildren, he had no idea who they were. When Squire asked if he remembered getting sick, Eugene said he had no recollection of his illness or the hospital stay. In fact, Eugene almost never recalled that he was suffering from amnesia. His mental image of himself didn’t include memory loss, and since he couldn’t remember the injury, he couldn’t conceive of anything being wrong.
In the months after meeting Eugene, Squire conducted experiments that tested the limits of his memory. By then, Eugene and Beverly had moved from Playa del Rey to San Diego to be closer to their daughter, and Squire often visited their home for his exams. One day, Squire asked Eugene to sketch a layout of his house. Eugene couldn’t draw a rudimentary map showing where the kitchen or bedroom was located. “When you get out of bed in the morning, how do you leave your room?” Squire asked.
“You know,” Eugene said, “I’m not really sure.”
Squire took notes on his laptop, and as the scientist typed, Eugene became distracted. He glanced across the room and then stood up, walked into a hallway, and opened the door to the bathroom. A few minutes later, the toilet flushed, the faucet ran, and Eugene, wiping his hands on his pants, walked back into the living room and sat down again in his chair next to Squire. He waited patiently for the next question.
At the time, no one wondered how a man who couldn’t draw a map of his home was able to find the bathroom without hesitation. But that question, and others like it, would eventually lead to a trail of discoveries that has transformed our understanding of habits’ power. [15] It would help spark a scientific revolution that today involves hundreds of researchers who are learning, for the first time, to understand all the habits that influence our lives.
As Eugene sat at the table, he looked at Squire’s laptop.
“That’s amazing,” he said, gesturing at the computer. “You know, when I was in electronics, there would have been a couple of six-foot racks holding that thing.”
In the first few weeks after they moved into their new house, Beverly tried to take Eugene outside each day. The doctors had told her that it was important for him to get exercise, and if Eugene was inside too long he drove Beverly crazy, asking her the same questions over and over in an endless loop. So each morning and afternoon, she took him on a walk around the block, always together and always along the same route.
The doctors had warned Beverly that she would need to monitor Eugene constantly. If he ever got lost, they said, he would never be able to find his way home. But one morning, while she was getting dressed, Eugene slipped out the front door. He had a tendency to wander from room to room, so it took her a while to notice he was gone.
