H. M., an
Unforgettable Amnesiac, Dies at 82
New York Times obit
Published: December 4, 2008
He knew his name. That
much he could remember.
He knew that his father’s family came from
Thibodaux, La., and his mother was from Ireland, and he knew about the 1929
stock market crash and World War II and life in the 1940s.
But he could remember
almost nothing after that.
In 1953, he underwent an
experimental brain operation in Hartford to correct a seizure disorder,
only to emerge from it fundamentally and irreparably changed. He developed a
syndrome neurologists call profound amnesia. He
had lost the ability to form new memories.
For the next 55 years,
each time he met a friend, each time he ate a meal, each time he walked in the
woods, it was as if for the first time.
And for those five
decades, he was recognized as the most important patient in the history of
brain science. As a participant in hundreds of studies, he helped scientists
understand the biology of learning, memory
and physical dexterity, as well as the fragile nature of human identity.
On Tuesday evening at
5:05, Henry Gustav Molaison — known worldwide only as H. M., to protect his
privacy — died of respiratory
failure at a nursing home in Windsor Locks, Conn. His death was confirmed
by Suzanne Corkin, a neuroscientist at the Massachusetts
Institute of Technology, who had worked closely with him for decades. Henry
Molaison was 82.
From the age of 27, when
he embarked on a life as an object of intensive study, he lived with his
parents, then with a relative and finally in an institution. His amnesia did
not damage his intellect or radically change his personality. But he could not
hold a job and lived, more so than any mystic, in the moment.
“Say it however you
want,” said Dr. Thomas Carew, a neuroscientist at the University of California,
Irvine, and president of the Society for Neuroscience. “What H. M. lost, we now
know, was a critical part of his identity.”
At a time when
neuroscience is growing exponentially, when students and money are pouring into
laboratories around the world and researchers are mounting large-scale studies
with powerful brain-imaging technology, it is easy to forget how rudimentary
neuroscience was in the middle of the 20th century.
When Mr. Molaison, at 9
years old, banged his head hard after being hit by a bicycle rider in his
neighborhood near Hartford, scientists had no way to see inside his brain. They
had no rigorous understanding of how complex functions like memory or learning
functioned biologically. They could not explain why the boy had developed
severe seizures after
the accident, or even whether the blow to the head had anything do to with it.
Eighteen years after that
bicycle accident, Mr. Molaison arrived at the office of Dr. William Beecher
Scoville, a neurosurgeon at Hartford Hospital. Mr. Molaison was blacking out
frequently, had devastating convulsions
and could no longer repair motors to earn a living.
After exhausting other
treatments, Dr. Scoville decided to surgically remove two finger-shaped slivers
of tissue from Mr. Molaison’s brain. The seizures abated, but the procedure —
especially cutting into the hippocampus, an area deep in the brain, about level
with the ears — left the patient radically changed.
Alarmed, Dr. Scoville
consulted with a leading surgeon in Montreal, Dr. Wilder Penfield of McGill University, who with
Dr. Brenda Milner, a psychologist, had reported on two other patients’ memory
deficits.
Soon Dr. Milner began
taking the night train down from Canada to visit Mr. Molaison in Hartford,
giving him a variety of memory tests. It was a collaboration that would forever
alter scientists’ understanding of learning and memory.
“He was a very gracious
man, very patient, always willing to try these tasks I would give him,” Dr.
Milner, a professor of cognitive neuroscience at the Montreal Neurological
Institute and McGill University, said in a recent interview. “And yet every
time I walked in the room, it was like we’d never met.”
At the time, many
scientists believed that memory was widely distributed throughout the brain and
not dependent on any one neural organ or region. Brain lesions, either from
surgery or accidents, altered people’s memory in ways that were not easily
predictable. Even as Dr. Milner published her results, many researchers
attributed H. M.’s deficits to other factors, like general trauma from his
seizures or some unrecognized damage.
“It was hard for people
to believe that it was all due” to the excisions from the surgery, Dr. Milner
said.
That began to change in
1962, when Dr. Milner presented a landmark study in which she and H. M.
demonstrated that a part of his memory was fully intact. In a series of trials,
she had Mr. Molaison try to trace a line between two outlines of a five-point
star, one inside the other, while watching his hand and the star in a mirror.
The task is difficult for anyone to master at first.
Every time H. M.
performed the task, it struck him as an entirely new experience. He had no
memory of doing it before. Yet with practice he became proficient. “At one
point he said to me, after many of these trials, ‘Huh, this was easier than I
thought it would be,’ ” Dr. Milner said.
The implications were
enormous. Scientists saw that there were at least two systems in the brain for
creating new memories. One, known as declarative memory, records names, faces
and new experiences and stores them until they are consciously retrieved. This
system depends on the function of medial temporal areas, particularly an organ
called the hippocampus, now the object of intense study.
Another system, commonly
known as motor learning, is subconscious and depends on other brain systems.
This explains why people can jump on a bike after years away from one and take
the thing for a ride, or why they can pick up a guitar that they have not
played in years and still remember how to strum it.
Soon “everyone wanted an
amnesic to study,” Dr. Milner said, and researchers began to map out still
other dimensions of memory. They saw that H. M.’s short-term memory was fine;
he could hold thoughts in his head for about 20 seconds. It was holding onto
them without the hippocampus that was impossible.
“The study of H. M. by
Brenda Milner stands as one of the great milestones in the history of modern
neuroscience,” said Dr. Eric Kandel, a neuroscientist at Columbia University. “It
opened the way for the study of the two memory systems in the brain, explicit
and implicit, and provided the basis for everything that came later — the study
of human memory and its disorders.”
Living at his parents’
house, and later with a relative through the 1970s, Mr. Molaison helped with
the shopping, mowed the lawn, raked leaves and relaxed in front of the
television. He could navigate through a day attending to mundane details —
fixing a lunch, making his bed — by drawing on what he could remember from his
first 27 years.
He also somehow sensed
from all the scientists, students and researchers parading through his life
that he was contributing to a larger endeavor, though he was uncertain about
the details, said Dr. Corkin, who met Mr. Molaison while studying in Dr.
Milner’s laboratory and who continued to work with him until his death.
By the time he moved into
a nursing home in 1980, at age 54, he had become known to Dr. Corkin’s M.I.T.
team in the way that Polaroid snapshots in a photo album might sketch out a
life but not reveal it whole.
H. M. could recount
childhood scenes: Hiking the Mohawk Trail. A road trip with his parents. Target
shooting in the woods near his house.
“Gist memories, we call
them,” Dr. Corkin said. “He had the memories, but he couldn’t place them in
time exactly; he couldn’t give you a narrative.”
He was nonetheless a
self-conscious presence, as open to a good joke and as sensitive as anyone in
the room. Once, a researcher visiting with Dr. Milner and H. M. turned to her
and remarked how interesting a case this patient was.
“H. M. was standing right
there,” Dr. Milner said, “and he kind of colored — blushed, you know — and
mumbled how he didn’t think he was that interesting, and moved away.”
In the last years of his
life, Mr. Molaison was, as always, open to visits from researchers, and Dr.
Corkin said she checked on his health weekly. She also arranged for one last
research program. On Tuesday, hours after Mr. Molaison’s death, scientists
worked through the night taking exhaustive M.R.I. scans of his
brain, data that will help tease apart precisely which areas of his temporal
lobes were still intact and which were damaged, and how this pattern related to
his memory.
Dr. Corkin arranged, too,
to have his brain preserved for future study, in the same spirit that
Einstein’s was, as an irreplaceable artifact of scientific history.
“He was like a family
member,” said Dr. Corkin, who is at work on a book on H. M., titled “A Lifetime
Without Memory.” “You’d think it would be impossible to have a relationship
with someone who didn’t recognize you, but I did.”
In his way, Mr. Molaison
did know his frequent visitor, she added: “He thought he knew me from high
school.”
Henry Gustav Molaison,
born on Feb. 26, 1926, left no survivors. He left a legacy in science that
cannot be erased.