It’s hard to sympathize with Gilderoy Lockhart in Harry Potter and the Chamber of Secrets. He’s a self-absorbed narcissist who seems rather inept at most magic, except for the Memory Charm which he uses effectively to remove the memories of wizards and witches who have done great magical deeds so that he can claim such deeds for himself. This leads to a career as an author and celebrity. Lockhart is good at selling an oversized image of himself.
In the one instance when Gilderoy tries to use the spell, Obliviate, to burnish his reputation once more, he unwittingly uses an almost-broken wand that causes his spell to backfire. Stupendously in this case because he seems to have erased all his memories and has no idea who he is anymore or of any past events in his life. This crass damage is actually the more likely outcome in real life. We’ve learned a lot about how the human brain works by mishaps from people who’ve had accidents that caused severe lesional damage to their brains, and from early medical practices of lobotomy – removing chunks of the brain in the hope of reducing ill-understood maladies such as epilepsy. A most famous case in psychology or neuroscience books is patient H.M. who had major memory problems after being lobotomized, and then happily allowed himself to be studied and tested over decades. Of course he couldn’t remember any of this.
Gilderoy’s specializing in using Obliviate with surgical-like precision is actually very remarkable, given the complexities of the human brain. To erase a memory associated just with a singular event which was likely highly emotional and dramatic is actually very challenging – especially if you want to leave the unwitting suspect none the wiser. Even more so, if the event was not recent and likely lodged in long-term memory. You can’t just turn on a blue-flashing light and slam people with electromagnetic radiation as the Men in Black do. Neuralyzing, they call it.
Memory and cognition are tricky things. I’ve been marveling at the complexity of how our human brains do what they do, as I’ve been reading through The Idea of the Brain by Matthew Cobb. The year is 1950 and Karl Lashley is giving a seminar at Cambridge reviewing his long studies on memory. The title: “In Search of the Engram”. What is an engram? Apparently, it means “the physical trace of a memory”. Are memories physically located in certain areas of the brain? And if we knew exactly where they were, could we mess with them, or even remove them? (A dramatic view of how this might play out can be seen in the movie Eternal Sunshine of the Spotless Mind.)
More well-known in the field than Lashley is his former student Donald Hebb. Both Lashley and Hebb thought that memory was distributed throughout the brain rather than localized in a particular area. Hebb is also associated with some great quotes. Referring to neuron activation and synapse development, Hebb’s theory is couched in the memorable “cells that fire together wire together”. One quote that I particularly like, referring to the dualist brain-mind arguments of the day: “Our failure to solve a problem does not make it insoluble. One cannot logically be a determinist in physics and chemistry and biology, and a mystic in psychology.”
Then there’s the “grandmother” cell. Cobb relates the funny story of how it came about as an extrapolation of the work of the Russian neurosurgeon Akakhievitch (you’ll have to read the book to find out more!), and how “it was used as a shorthand way of underlining the inherent silliness of suggesting that every object we recognize, whatever its orientation or context, is represented by the activity of a particular cell or group of cells. Taken to its absurd conclusion, there would have to be a cell for your grandmother sitting, your grandmother standing on her head, your grandmother playing the ukulele, and all possible combinations of the infinite variations in which you could recognize your grandmother.”
And then there’s the famous 2005 study by Fried and Koch. Apparently, after inseting electrodes into the brains of patients (who were being prepped for surgery for severe epilepsy), they showed images to patients and recorded the activity of individual hippocampal cells. The results are mind-boggling: “In one case, a unit responded only to three different images of the ex-president Bill Clinton. Another unit (from a different patient) responded only to images of the Beatles, another one to cartoons from The Simpsons…” And most strikingly, “one patient possessed a single unit in the left posterior hippocampus active exclusively by different views of the actress Jennifer Aniston. The cell did not respond if Aniston was pictured with her then partner, Brad Pitt. In another patient, a cell responded consistently to pictures of the actress Halle Berry, including when she was dressed up as Catwoman…”
What is one to make of all this? Cobb writes that “the authors were more cautious – although the cells responded consistently to Aniston or Berry or Clinton, that did not mean that these were the only stimuli that could potentially excite these cells – the patients had been shown only a very limited range of pictures… just because a single cell responded to an image, that did not mean it was the only cell involved in recognizing the image, merely that it was the only cell they had recorded from that belonged to the relevant network. They estimated that a million neurons would be activated by each stimulus…”
I agree with Cobb when he argues that a significant limitation of our understanding comes from the helpful (yet limiting) reductionist approach – take things apart to find how each part works. The key issue is that “function is both localized and distributed – or rather, to be clearer, both terms are misleading: localization is rarely precise, and distributed functions are also localized to particular networks and cells, even if these may sprawl over the brain. Brain function therefore involves both segregation and integration.” A long-standing dictum employed in neuroscience – that location implies function (or “where is how”) – needs to be re-thought. A related dictum we face in chemistry and biochemistry is that structure implies function. But when we get to systems chemistry, this reductionist stricture becomes very problematic.
Let’s get back to Gilderoy. If engrams and grandmother cells exist as localized patches, he’d have to be an exceedingly able wizard to isolate those patches without causing severe harm to his victims (which might then implicate him and reveal his thievery). Perhaps one of the reasons why he’s a bungler at most other magic is that he doesn’t practice it because of his exclusive concentration on perfecting the Memory Charm. Messing with the brain too much though, should start to produce side effects. Legilimency, the Imperius curse, and even the seemingly simpler Confundus! might start to cause longer-term degeneration. There are hints of this in the Harry Potter series where victims seem to become more susceptible to further break-ins to their brain and executive functions.
Hermione is praised as the greatest witch of her age. In the final book, she removes the memory of herself from her parents – likely requiring great magical skill made even more difficult by the emotional challenge of the very act. This is one instance where the movie does a better job than the book in conveying the drama of Hermione’s Obliviate. And it reminds me that Lockhart may not be simply a magical oaf with poor skills. Obliviate is much, much harder than it looks.
P.S. For a previous post on memory, and The Chamber of Secrets, see here.
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