It hardly needs to be said that one of the greatest obstacles a medical student must overcome in their quest for a golden, shiny MD degree (it is golden and shiny, right?) with their name on it is the prodigious volume of information they have to cram into their head, but I will say it anyway: one of the greatest obstacles a medical student must overcome in their quest for a golden, shiny MD degree with their name on it is the prodigious volume of information they have to cram into their head. Just how much information are we talking about? While it is difficult to give a quantitative answer (e.g., “105,219.31 facts”), various qualitative answers are possible. It could, for instance, be submitted that the amount of information is: overwhelming; obscene; mind-boggling; disheartening; insane; nightmare-inducing; forbidding; like a black hole whose sole purpose is to suck away one’s free time; the sort of thing that makes one ask, “Why?”; enough to sink a ship; enough to sink a medical student; enough to sink a ship made of medical students (whatever that means); not conducive to either weekend or holiday relaxation; perhaps metaphysically impossible to master; and so large that it can make one brew some sugar cookie tea at 2 AM on a Friday morning, curl up into a ball, rock back and forth in a dusty corner of their apartment, mumble incoherently to themselves until the Sun comes up, and not even remember to drink the tea. Seriously, we’re dealing with a lot of information here.
How exactly I could successfully learn and remember a lot of information was a topic that preoccupied me for several weeks last summer as I was preparing to get things started at UTMB. From personal experience I knew that rote repetition, while perhaps effective for managing small amounts of information, and while perhaps effective for others, wasn’t going to work for me, based on what I had heard about the intellectual demands of medical school. If I try to remember something by reading it, then instantly reading it again, then instantly reading it one more time, then waiting 10 minutes and reading it again, then reading it again the next day, then waiting three days and reading it one last time, I’ve found that the information I took in will have very likely fallen out within about a month, if not a handful of days. So, I decided to do some research on memory techniques, of which there are actually a decent number. But there was one technique that stood out to me as the most bizarre, but also the most promising one among those I looked into. This would be the method of loci, or, more informally, the “mind palace technique.” (Yes, the one made famous by the [quite sterling] BBC series Sherlock.) Here I wish to briefly explain the technique, discuss how to use it most effectively, and hopefully encourage a reader or two––whether or not they are medical students––to give it a whirl. There’s no way this is going to resemble a comprehensive introduction, but towards the end I’ll provide a couple of helpful resources for the interested reader.
The basic idea behind the method of loci is that humans generally have quite good visual and spatial memory (to lump, for simplicity, the two types of memory together), but not so good semantic memory, or memory of facts, ideas, concepts, and other abstractions. This is simply a brute fact of human psychology; it’s the way we’re wired, as it were. If, to give a simple demonstration of the point, I were to give you a page of writing that indicates where you would find 30 different items in a particular grocery store (e.g., canned beans in aisle 9, vegetables in aisle 1, sugar cookie tea in aisle 7, etc.), and I said that you only have five minutes to study the list, then, if you’re like me, odds are that you’ll forget where at least some of the 30 items are soon after the five minutes of study time have elapsed, assuming you use rote repetition alone to study the list. But now suppose that instead of handing you any sort of written list I actually take you to the grocery store and, in the span of five minutes, show you where you might find the 30 different items found on the aforementioned list. Would you have an easier time recalling the items and their locations in this scenario than you did in the previous scenario? For the simple reason that our visual and spatial memory typically outperforms our semantic memory when it comes to long-term recall, I believe you would.
Whether or not the example is worth anything, the basic idea behind the method of loci remains. How exactly does the method put it to use? In a sentence, the method of loci involves taking any amount of information you want to learn, imagining figures or scenes which represent that information, placing these figures or scenes at certain spots (“loci”) in one or more imagined settings, and then––again with the aid of the imagination––“walking through” these settings and observing the images that have been placed there to (ideally) recall all of the information which is represented by the figures and scenes. This is a good way to remember things for many reasons, but the primary reason––the reason so-called “memory athletes” are able to perform such impressive feats as memorizing 3,000 or so random digits in under an hour––is that in placing your chosen images in spatial, albeit imagined, settings, you’ll be relying upon your visual and spatial memory. And visual and spatial memory, as I’ve suggested, is the “reliable” memory, the veritable Samwise Gamgee of the mind that can forever be trusted to carry you to the top of Mount Memory when your semantic memory gives out as soon as the going gets tough, whether this be at the bottom of the mountain or twenty feet beyond the borders of the Shire. The net result of utilizing the method? You can, in theory, memorize a lot more information with it than you can with any technique that relies on semantic memory alone, such as rote repetition or acronyms.
Now, I could continue to bore you with the method of loci’s theory, or I could give an example of the method at work, and intersperse it with bits and pieces of theory. Something tells me the latter route is the better one, so let’s go with it. In the course I’m taking right now––Pathobiology and Host Defenses––I’m learning microbiology, i.e., the science of tiny organisms. So let’s open up the 2016 edition of First Aid for the USMLE Step 1 to the microbiology section and find something to memorize using the method of loci. How about the first five rod-shaped bacterial species that have a “gram-positive” staining pattern? Yes, this should do. Here are the five species:
To learn these bugs, let’s begin by imagining a place whose general layout we can remember. It can be a middle school, a movie theater, a clothes closet, Niagara Falls, or a Super Mario 64 level. So long as we’ve got a pretty idea of what the place is like, it’ll work. Next, let’s run through the list of bacteria and, for each species, come up with an image which will help us remember it. The images can be anything, really, but it’s best to have images which will consistently make us think of the information we’re trying to learn. For Bacillus we might imagine the Greek god Bacchus dancing around (because “Bacillus” kind of sounds like “Bacchus”); for Clostridium we might imagine a claustrophobic individual stuck inside a one-person submarine and desperately trying to escape (because “Clostridium” and “claustrophobic” are similarly structured); for Corynebacterium we might imagine a giant, Jabba the Hutt-like bacterium scarfing down a pile of corn kernels (because “coryne” makes me think of corn); for Gardnerella we might imagine Gregor Mendel––the father of modern genetics––working in his garden (because “gardener” is, for all intents and purposes, phonetically contained in “Gardnerella”); and for Lactobacillus we might imagine a glass of putrid milk (because “lacto-” brings lactose to my mind, and “-bacillus” does the same for bacteria, and thus expired food).
Now we imagine the place we began with. How does it look? Stable and pristine? Good; that’s our cue to add the images. We start with Bacillus. For my setting I’m using the refrigerator in my apartment. This doesn’t earn me many points for creativity, but, hey, it’ll do. (If you haven’t come up with a setting of your own, I invite you to take a peek inside your fridge now so that you can follow along, assuming you don’t have some futuristic, high-tech fridge that doesn’t resemble mine.) Alright then, I open the door of my refrigerator to find––heavens above!––the Greek god Bacchus dancing around on the top shelf! He’s a tad small, for sure, but that’s Bacchus alright. Next we have our poor claustrophobic individual (if you have an arch-nemesis who happens to be claustrophobic, you can use them) trying to get out of a one-person submarine; I’ll put them on the middle shelf. Then we have our Jabba the Hutt-like bacterium eating corn kernels. He (it?) can go on the bottom shelf. The last two are Gregor Mendel and the glass of putrid milk. They can go in the vegetable and meat drawers, respectively, so that if I were to open both drawers in my imagination I would be greeted by them.
Our images are in place, and because we humans have such darn good visual and spatial memory, they’re likely to remain right where we put them for some time. But there are at least three things we can do to our images around the time of their placement, in this example as well as in any use of the method of loci, to prolong their longevity in our imagination. Firstly, it helps to have the images moving around and interacting with their environment, and perhaps with one another. Some of our images are already doing that––Bacchus, for example––but others––the glass of putrid milk, for instance––are not. So let’s imbue some life into our glass of milk, which is the most static image among our five. The fix is pretty easy: we can just give the glass arms, legs, and a tail, and we’ll have it run around the meat drawer, spilling its smelly, moldy contents all over the place. That gross enough for you? If so, that’s a good sign this image in particular is going to stick in your memory. This brings me to the second thing we can do to enhance the longevity of our images: make them as outlandish as possible. Seriously, the more humorous and offbeat an image is, the longer its shelf life, metaphorically and, in this case, literally. So perhaps we can make Mendel––to pick on just one image––wear a pink jumpsuit, or something attention-grabbing like that. Whatever stands out to you. Thirdly, and finally, it’s to our advantage to activate as many of our sense modalities as possible when placing our images. For instance, before placing our glass of putrid milk––to mess with it some more––in the meat drawer, we can imagine taking a sip of its contents and then spewing whatever we drank all over the place (for the obvious reason that it tastes like a bucket of blended compost); smelling the milk’s rot; touching some of its mold; and hearing its contents slosh around as we set the glass in the drawer. Since we’ll be looking at the glass with our mind’s eye as we do all of these things, we won’t need to single out sight for special treatment.
Okay, we have our images, and we’ve tricked them out to improve their longevity. Let’s take a final look at them, and then close the refrigerator door. Our work here is done.
What have we accomplished in this short exercise? If all goes well, we’ve managed to learn the five species of bacteria listed above in a manner that’s fun and––perhaps more importantly––robust. If you placed images corresponding to our five species of bacteria in a certain imagined setting, whether this setting was your refrigerator or somewhere else, and whether you used my images or your own, you should find, upon waking up tomorrow, that those images are still there in your imagination, and that you can accurately interpret them. And you should wake up the next day to find the same thing. And the next day. And the next day. And…well…I can’t say that these images will last forever, as even the best designed images often fade away or grow static if they aren’t reviewed every now and then. But boy will they (or, at least, whatever they represent) last you a long time if you’re using the technique more or less correctly, and if you’re reviewing your images and their meanings on a daily or weekly basis.
Of course, bacteria are the not the only thing you can memorize with the method of loci. You can, in truth, memorize just about anything with it: phone numbers, names, dates, grocery lists, laws, speeches, sacred texts, equations, maps, poetry, pi to 30,000 digits, songs, Aristotle’s Nicomachean Ethics, First Aid for the USMLE Step 1, First Aid for the USMLE Step 2, First Aid for the USMLE Step 3––the list goes on and on. The method is really that versatile.
In any event, if this pithy introduction to the method has piqued your interest, I’m going to suggest two resources which can teach you far more about the method than this post either can or has (assuming it taught you something). The first resource is a book with the apparently fanciful title of Moonwalking with Einstein: The Art and Science of Remembering Everything. It’s written by a journalist named Joshua Foer, and in it, Foer deftly mixes autobiography with history, neuroscience, and psychology to tell the story of how he went from knowing nothing at all about the method of loci to winning the 2006 USA Memory Championship with the method’s aid. It’s definitely a page-turner, and it gives the reader, if informally, much of the information they could want about how the method of loci works, why it works, and how they can put it to good use.
The other resource is the website of Alex Mullen, one of those “memory athletes” I mentioned earlier. Alex, to be more precise, is not your average, ordinary memory athlete. On the contrary, he is currently the world’s top memory athlete, and he holds several world records in memory competition events. An advocate of the method of loci, Alex has posted a number of videos on his website in which he introduces the method and demonstrates how to use it, and he’s written quite a bit about the method as well. Oh, and did I mention that he’s a medical student? No? Well, he is. And he can memorize over thirty decks of cards in under an hour. So…yeah, he’s undoubtedly an authority on the method of loci in general, and on the use of the method in medical contexts in particular. I’ve learned a lot from him in the months since I first heard about the method, and I bet that you can learn a lot from him too.
With that, I bid you adieu. Happy memorizing!