Dr. Brenda Milner: “A Tribute to H.M.”
Jason Gencher, Bachelor of Music
In the fall of 2012, I was lucky enough to attend some McGill homecoming events. Dawning my sports blazer, and McGill ’13 name tag, I slipped imperceptibly through the throngs of alumni, their eyes fixed on the campus they once were belligerent upon (O! Those unsung heroes who made McGill what is it today!). I did catch some interesting lectures, apart from free meals, one of which was given by that unforgettable name in the field of cognitive neuropsychology, Dr. Brenda Milner.
Dr. Milner, in her 96th year and still as vibrant as she was 50 years ago (or what I would assume she was like, 29 years before I was born), gave a presentation on the subject which brought her such fame in her field, that of H.M., or whom we can now reveal as Henry Molaison.
Mr. Molaison suffered from terrible epilepsy for most of his young life, resulting in a radical surgery whereby a Dr. William Scoville removed sections of both his temporal lobes, his hippocampus, and some of the surroundings structures. This surgery was so radical, as Dr. Milner pointed out in her presentation, because it was bilateral. This sort of procedure was very rare, and made many neurosurgeons uncomfortable (including Dr. Penfield, whom Brenda also studied with). In most surgeries of the brain, if the surgeon removes the structure on the left side, the ‘copy’ on the right side will be able to step in and partially restore any lost function. Removing both medial temporal lobes, as in the case of Molaison, would have unknown consequences. The surgery occurred, and H.M. was by-and-large relieved of his constant epilepsy, which had impaired him to such a point that he could not sit through a meal without the possibility of a grand mal seizure. Yet, there were other, more disappointing consequences. He had lost all ability to commit new information to his explicit memory (short term), and suffered from severe anterograde amnesia (ability to create new memories).
While being a disaster for the patient, the outcome of the surgery was a boon for this field of science. As Milner explained, Henry Molaison was from that point on, the most sought after person in neurology. Every doctor wanted a chance to observe him, and study the effects of this sort of disorder in humans. Milner was lucky enough to be invited down to Connecticut and observe H.M. on several occasions.
In her presentation, Dr. Milner describe the finding that she is most well known for, with regards to Mr. Molaison. She explains that before she left to catch the train to see H.M., she took some children’s developmental psychology ‘games’ for her visit with him. One of these was an activity whereby the child had to trace the inside of a simple geometrical object, in this case a star. Easy enough. The twist was that they had to do so by looking at the paper through a mirror, so all your movements effectively had to be the reverse of what you wanted to do. H.M. was able to complete the task, at first with several errors, as many of us would too. Milner would then pack up and return to Montreal. She would come back a few weeks later and try it again. Molaison was not able to recall who Milner was, and always had to be re-explained the task he had to accomplish in the activity. After repeated trials, he was able to complete the activity with little or no errors. This was evidence of learning. Milner had discovered that H.M. was able to learn, despite his obvious handicap of being unable to remember what he learned!
The neurology is of course, much more complicated than I make it seem. If H.M. was asked to remember a number, as Milner anecdotally told us in her lecture, he could only do so by repeating the information to himself, or using a confounding series of steps to arrive at the number he was given. The tracing activity involved acquiring new information in the cerebellum, and perhaps this is why he was able to do this, and not other memory activities. We still stand to learn a lot from Henry Molaison. After his death in 2008, his brain was sectioned and transferred for study to UC San Diego. The results of the analysis are anxiously awaited. And while one may argue that perhaps the most dangerous beast in the animal kingdom is a surgeon without a wait list, or that brain surgeons know only how to do one thing: remove, we should be able to comfort ourselves in knowing that H.M. still lived a humane life, and was always content in his stupor, despite some days looking himself in the mirror and commenting on how he was beginning to “look a bit like my father.”