'Only three movies ever made... portray amnesia with anything approximating accuracy' — Neuropsychologist Sallie Baxendale

The quotation above appeared last week in Jurek Martin's Financial Times obituary of Henry Molaison, "the most famous amnesiac in the history of neuroscience."

Martin's piece invoked "Memento," one of Baxendale's aforementioned three.

What are the other two?

Answer here this time tomorrow.

In the meantime, here's Martin's masterful obituary about Molaison, the man whose past never was.

The most famous amnesiac in the history of neuroscience

Tales of a man with no memory have been a staple of the movies since the silent era. In “Memento”, released to critical acclaim in 2000, the hero finds that after the killing of his wife he can remember nothing for more than a few moments. As he struggles to solve her murder he frantically records every thought, every discovery before it is blanked from his mind.

But it was not all fiction, as almost all movies about amnesia are. It had been inspired by the real life of the man known only to neuroscientists as HM, or sometimes Henry M, whose actual identity was revealed only after his death in Connecticut last week at the age of 82. He was Henry Gustav Molaison and he was, without doubt, the most famous and examined patient in the history of neuroscience.

He was born on February 26 1926 in Hartford, the son of a Cajun electrician from Thibodeaux, Louisiana, and an Irish mother. In 1953, HM underwent experimental brain surgery in Hartford to correct repeated epileptic seizures, which began after he had been knocked over by a bicycle when he was nine. They had become so frequent and severe that he could no longer hold down his job as a motor mechanic and all treatment had failed.

The surgeon, William Beecher Scoville, who had refined lobotomy techniques, removed two finger-length wedges of tissue from HM’s brain by cutting deep into its hippocampus. The seizures became infrequent but the patient’s life was radically, and forever, changed. He could remember his name and his early life but almost nothing that happened after he emerged from the operating table. Each experience, each face, was eternally new to him. Whatever he absorbed lasted in his mind for no more than about 20 seconds, yet his basic intelligence was unimpaired. He was the victim of “profound amnesia”, or, to give its technical term, severe anterograde amnesia. Scoville, conscience-stricken, contacted two Canadian physicians, Wilder Penfield and Brenda Milner, renowned for their work on memory loss. Dr Milner began to visit HM regularly. In this early period of neuroscience, knowledge of the brain was rudimentary, with widespread disagreements over the causes of amnesia. The memory function, it was assumed, was distributed throughout the brain and not dependent on one neural organ or region.

Dr Milner’s seminal study, based on her work with HM, was published in 1962. It revealed there were at least two systems in the brain responsible for creating memory; one was the subconscious, “motor learning”, by which people can remember how to perform basic tasks, such as riding a bicycle; the other, declarative memory, stores facts and experiences until they are consciously recalled. This was based in the hippocampus, part of which had been removed from HM’s brain.

Legions of researchers descended on Connecticut to examine neuroscience’s most famous patient, who was always extremely obliging, even if he could never remember who his repeated visitors were.

He lived at home, with his parents and later another relative, before eventually moving into a nursing home and was able to function at a basic level from what he could remember from the first 27 years of his life. He could prepare a meal, make his own bed and work in a garden. He was also able to do crossword puzzles, more of a motor skill. He had no problems with straightforward conversations. Dr Milner recently recalled him as “a very gracious man, very patient, always willing to try these tasks I would give him. And yet every time I walked into the room, it was like we’d never met.”

Suzanne Corkin, once a student of Dr Milner’s and now of the Massachusetts Institute of Technology, has similar fond memories of her long collaboration with HM, about whom she is writing a book. “He was like a family member. You’d think it would be impossible to have a relationship with someone who didn’t recognise you, but I did.” She added he tried to show recognition: “He thought he knew me from high school.”

She has arranged to have his brain preserved, much as Einstein’s was, for scientific posterity. Just after his death, she had a team of scientists taking extensive magnetic resonance images of his brain, trying to find out which areas of temporal lobes were damaged and which were not.

Art does not precisely imitate life in Memento, but, according to Sallie Baxendale, a neuropsychologist writing in the British Medical Journal in 2004, it is one of only three movies ever made to portray amnesia with anything approximating accuracy. Common plot devices depict memory loss after a trauma and recovery after another one or show the subject living a normal but different life, which, she writes, is “neurologically improbable”. Fictional film assassins, such as Jason Bourne, are particularly prone to forgetting what they have done.

Her comprehensive article, aptly titled “Memories aren’t made of this”, notes that “Memento” was “inspired partly by neuropsychological studies of the famous patient HM”.

It is not known if HM ever used photographs or scratched words in his skin to try to remember what he would forget in a moment, as the character Leonard does in the film, but, in most respects, it gets profound amnesia right. “The fragmented, almost mosaic sequence of scenes in the film also cleverly reflects the perpetual present nature of the affliction,” Dr Baxendale observed.

One can speculate on who might play HM in a film. The late Peter Sellers could have, as he did the simple-minded Chauncey Gardiner; also Dustin Hoffman, who portrayed the autistic-savant Raymond in "Rain Man," or Tom Hanks, reprising his role as Forrest Gump. Each character, while mentally flawed, achieved a certain serenity, as, apparently, did Henry Gustav Molaison. He had, after all, given his brain to science.