Yannick Grandmont for The New York Times
May 20, 2013
Still Charting Memory’s Depths
By CLAUDIA DREIFUS
MONTREAL — In many ways, the Obama administration’s new plan to map the human brain has its origins in the work of Brenda Milner, the neuropsychologist whose detailed observations of an amnesia patient in the 1950s showed how memory is rooted in specific regions of the brain.
“Prior to Brenda Milner’s discoveries, many behaviorists and some cognitive psychologists followed the lead of Freud and Skinner in abandoning biology as a useful guide to the study of memory,” the Nobel laureate Dr. Eric Kandel wrote in his memoir, “In Search of Memory.” “Milner’s work changed all that.”
The amnesia patient, Henry Molaison (known during his lifetime only as H.M., to protect his privacy), died at 82 in 2008; his brain is now being dissected and digitally mapped in exquisite detail.
But Dr. Milner is still very much alive. Two months short of her 95th birthday, she puts in full days at the Montreal Neurological Institute and Hospital, where she is studying left/right brain differences.
We spoke in her offices here at “the Neuro” and at the annual meeting of the American Association for the Advancement of Science in Boston. Here is a condensed and edited version of the conversations.
How did you come to work with H.M., perhaps the most famous patient in the history of neuroscience?
In 1950, while working on a doctorate at McGill, I went to work here at the Montreal Neurological Institute to study the patients of Dr. Wilder Penfield. He’d created the Neuro as a place to pioneer the neurosurgical treatment of epilepsy. He’d developed a procedure for patients who were having epileptic seizures because of brain injuries where he’d excise the injured part of the brain.
One of the things I did was to try to help Dr. Penfield pinpoint where the seizures were coming from. This was really detective work. In the early 1950s, there wasn’t imaging technology to let us see the brain anatomically. I used EEGs and developed tests based in part on research I was doing.
And then, within a short period of time, we saw two patients, P.B. and F.C., who presented with something we’d never seen before. After their surgery, their ability to form long-term memory was gone — though their immediate memory and intelligence remained intact. I remember P.B. saying, “What have you people done to my memory?” Dr. Penfield and I hypothesized that there was damage on one side of the brain that we couldn’t have seen, and when he excised the other side he deprived these patients of the function of the region. We then wrote that theory up and presented it in an abstract to a meeting of the American Neurological Association in Chicago.
Did that lead to your meeting H.M.?
Yes. Directly. Afterward, Dr. William Scoville, a surgeon in Hartford, telephoned and said, “I’ve just read your abstract and I’m seeing the same thing in an epileptic patient on whom I carried out an operation.” Dr. Scoville then invited me to come to Hartford to study this person. That patient was H.M.
What was H.M. like?
He was very pleasant. And he so wanted to be helpful. At the time I met him, he must have been in his late 20s. He’d had really terrible epilepsy ever since a childhood bicycle accident, and the surgery had been beneficial for that. But the excision had made it difficult for him to acquire new long-term memories.
There were things about the past he recalled, but he’d tell you the same joke over and over again, never remembering he’d told it to you earlier. No matter how many times you met him, he couldn’t remember you.
I would give him tests where he had to repeat a set of numbers — 5, 8, 4. He could do it by constantly repeating those numbers to himself or making up formulas. Yet, if I distracted him — and life is constantly distracting — he could no longer give you 5, 8, 4. This was the heart of his incapacity.
What kinds of tests did you give him?
I had to show what he could learn and not learn. It was no good to say, “I have this patient and he cannot learn anything new,” because someone will say, “Brenda, what did you try to teach him?”
So I would hop on a train and go down to Hartford and give H.M. tasks based on learning. One was a puzzle where he had to trace his way out of a maze. He just couldn’t do it. A different one involved giving him a five-pointed star and asking him to trace its outlines while looking in a mirror. This looks easy, but is not. With most people, the more they practice, the better they get. This is really a test for motor-skill learning. Well, H.M. did it!
Seeing this was probably the most exciting thing that ever happened to me. As H.M. tried tracing the star — over 30 times in a three-day period — he showed a beautiful learning curve. He couldn’t recall any of the 30 tries, but he got better.
What did that mean?
That there are different kinds of learning and that autobiographic memory, or long-term memory, isn’t the whole of memory.
In the 1950s, what was the prevailing idea about memory?
There was this strange idea that memory was a function of the whole brain. The breakthrough was really to show that you couldn’t talk about memory as a great global function of the whole brain. It’s very dependent on particular areas.
But also that memory itself is multifaceted. Our memory is our autobiography, and H.M.’s autobiographical memory had been disturbed. After a critical part of his brain had been removed, H.M. couldn’t build up memories of his life as he lived it. At the same time, he could acquire some motor and some perceptual skills, which meant that there were different forms of learning and they involved different systems of the brain.
Did you like H.M.?
We all loved H.M. Yet it was very strange, psychologically, because when he died we all felt as if we’d lost a friend. And this is funny because one thinks of friendship as a bilateral thing. He didn’t recognize us or know us, and we felt we’d lost a friend.
You’re British. How did you come to live and work in Canada?
During World War II, I was a civilian research officer employed by the British Ministry of Supplies. And it was there that I met Peter Milner. He designed equipment to measure the tracking skills of radar operators. As a psychologist, I was charged with trying out these systems out on people. Well, every now and then the thing I was testing would break down and I’d have to call in Peter. Soon Peter was interested in psychology and I was interested in Peter. Radar brought us together.
Around 1944, he was asked to be part of a team setting up research on the beginnings of Canadian atomic energy. We hadn’t intended to get married. I had never intended to marry anyone because I never wanted children. But it was marriage or goodbye, and we weren’t ready yet for goodbye. So we got married, and three weeks later we departed for the New World.
We divorced in the 1970s. There were reasons, but we remained perfectly friendly and we spoke every day. We never stopped being friends. He’s my best friend. We go to the movies. We cook meals. We don’t live together. We live a few blocks from each other.
You are 95 and you still work —
I’m 94! I like to tell cabdrivers my age because they say, “You don’t look it.”
And yes, I do work. I have postdocs. I’ve always been interested in how the two sides of the brain work, and now, with functional M.R.I., we can see so much more. Now I won’t take on students going for their doctorates. That’s a five-year commitment. You don’t want to leave them stranded, if something happens to you.
You know, my mother, a music teacher, worked until she was 88. She would have stayed longer at her profession, but her hearing went and a music teacher must be able to hear.
How’s your memory?
Oh, it’s terrible, thank you. You forget things — names. But fortunately, I’ve discovered that there are quite a lot of people, not only people my age, who forget names.