Around the New Year, a couple of things happened that I meant to post about, but haven't got round to until now. One of those was the fact that the character of Popeye is now in the public domain within the EU, but really, aside from putting a few pictures of Popeye in the post there's not a lot I can do with that.
Above: Public domain in the EU. Which is where the server hosting it happens to be. Har.
So let's look at the other (and rather sadder) event that happened around Christmas: the death of Henry Molaison, known to thousands of psychology students simply as "HM".
I first learnt about HM in my first year at university, when I was first being introduced to the neurophysiology behind memory. It's a fearsomely complicated topic — we spent a considerable time covering the debate about what the different kinds of memory even were, let alone how they worked — and it was impressed on us very quickly that there is no single part of the brain that "does" memory. We learnt about Karl Lashley, the American
And then, bringing it all into clear and frighteningly relevant focus, along came HM. He was born in 1926, and developed very severe epilepsy at a young age. In an attempt to cure him that some would describe as "experimental" and others would describe as "ludicrously reckless", surgeon William Scoville removed pretty much all of his posterior hippocampus, along with a few other bits that he wasn't even aiming for. In case you're a bit rusty on your neuroanatomy, the hippocampus is a small, seahorse-shaped bit of brain, buried deep in its craggy folds, which is instrumental in the formation of short-term memories and in spatial reasoning.
"Why, that's foolish," you're probably thinking. "If Scoville knew that, why on earth did he remove it?" Well, he didn't know it at that point. Indeed, the main reason we know anything about the role of the hippocampus in laying down memories is that HM, immediately after recovery from the operation, was entirely unable to remember anything that had happened more than a few hours previously.
Although he was cured of epilepsy, HM was now suffering from a condition called anterograde amnesia. This isn't the type of amnesia that Hollywood loves so much, where you forget who you are but otherwise function perfectly normally (that's retrograde amnesia, and is usually considerably more debilitating than your average schmaltzy matinee movie would have it). Instead, HM remembered most of the events that took place up to his operation, but woke up each morning with no idea of what had happened since then.
It's a testament to the strength of HM's personality that he didn't go completely insane. Scoville, presumably in an attempt to work out which bits of the brain he shouldn't take out next time, worked closely with him for years afterwards, but every day HM met him for the first time. Every day he had to learn what was wrong with him, every day he had to come to terms with a world that was unaccountably no longer in 1953. Worse than that, he had to cope with the vast numbers of people who knew absolutely everything about him, but who (as far as he could tell) he had never met.
One of the insights that HM brought us was the difference between episodic memories (those about a particular event) and procedural memories (those covering general abilities and knowledge that you don't realise you know). Although he couldn't form the episodic memories necessary to remember one day to the next, he did pick up skills. One of my tutors told me, for example, that HM was a stunningly good table-tennis player, despite thinking that he had never played it before — years of playing his first game again and again had left their mark. Essentially, he lived a reverse Groundhog Day — the world moved on, while he went round in circles.
Back on my old blog, I posted a quotation from HM that was in one of my textbooks. I'll repost it here:
"Every day is alone in itself, whatever enjoyment I've had, and whatever sorrow I've had...
Right now, I'm wondering. Have I done or said anything amiss? You, see at this moment, everything looks clear to me, but what happened just before?
That's what worries me.
It's like waking from a dream; I just don't remember."
Well, if Dory's words back in this post were sad, that should have you bawling. HM was isolated from the world in a way that we can't imagine, unable to form any lasting relationships, and presumably aware every day that all he was experiencing was about to ebb out of his mind, never to return. Even though he was famous (albeit among a very specific section of the population), he remained anonymous to all those who knew about him, known to us all just by his initials.
On the 2nd of December last year, Henry Gustav Molaison died of respiratory failure in a nursing home in Connecticut. I didn't know his name or see his picture until after his death, but even so, I wish I'd met him. He contributed enormously, without knowing he was doing it, to one of the most fascinating and important branches of science affecting us today, and he lived one of the most difficult lives imaginable, by all accounts in a gracious and polite way.
Wherever he is now, I hope Henry is remembering everything that happened to him, all the people he ever saw, and all the ways he was able to make a difference.
And I hope he's playing a mean game of table tennis.
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