A memory palace seems like an inefficient way to learn, unless it's for a memorization stunt. At least, that's what it seems like as a beginner. It's slow, requires a very peaceful frame of mind, and isn't the kind of thing you can just dip into when needed in a time crunch. Nor does it make you better at the sort of fast calculations you get on an exam. Flash cards and homework seem like a more efficient way to grind in order to improve your speed and accuracy of recall.
We now have fast tools for information retrieval and visualization. It's usually more efficient to build a personal reference sheet than to construct a memory palace, unless you're trying to count cards.
Yet my experiences with visualization practice and memory palaces have been intriguing. I want to outline some of the benefits I've seen.
1) Constructing a memory palace makes textbook reading more engaging and focused.
Textbooks are dry, dense, and full of explanations that eventually become distractions from the information you're searching for. A memory palace turns dry prose into a far more engaging multi-sensory experience. When you're already in a peaceful, relaxed frame of mind, the dense charts and long lists of equations become interesting memorization challenges rather than dry references. I can study far, far longer if I'm visualizing the material than if I'm just scanning words on a page, trying to figure out which equations I'll need for the next test.
School does not incentivize this kind of scientific reading for pleasure, or even suggest it might be possible. It 100% incentivizes students to calculate, calculate, calculate, and to get their gratification from high grades. This is a disgusting outcome, and I see visualization practice as a way to reclaim your own mind and imagination from this Molochian trap.
2) Visualization lets you see what you know all at once.
I'm a classically trained pianist, and the trouble with audio/kinetic memorization is that you can only hold one posture or sound in your head at a time. At least that I'm aware of. Audio/kinetic memory can also be fragile. Ever tried to play a piece of classical music, hit a single point in the music where you can't remember what comes next, and just found yourself looping and floundering at the stuck place?
With the visual sense, we can all keep track of many objects all at once, and it's effortless to observe them. We might drop details. But because we're often imagining the thing itself (the molecular diagram, a 3D map with labeled extreme values, a photograph of a person), we have some structure available to help us fill in the blanks.
That makes it easy to go over a list. If you've placed 7 objects on a table in your mind palace, you just have to stand back and look at it. No more depending on remembering a sequence of words in the same order they were presented to you.
3) A memory palace helps you relate and understand concepts.
In my gen chem textbook, electronegativity and formal charge are presented in the same chapter, but are separated by a few sections. I understood how nuclear size and electron configuration gave rise to electronegativity, and I understood how electronegativity was important in determining which formal charge made for the best atomic diagram. But I hadn't thought at all about relating nuclear size and electron configuration to formal charge.
Scott Alexander's piece on mental mountains keeps coming back to me. Visual thinking seems to allow you hold up chunks of your memory that weren't formed together, and let the mind's natural tendency to find patterns go to work. If you're studying science, this is productive, because the whole idea is that it all links together. I visualize each textbook chapter as a room in my mind. But I can look through the doors into the other rooms and see the objects inside.
4) Visualization practice and memory palaces make you more able to see and manipulate 3D structures.
We've all had the experience of looking at a complex 3D image and not being able to untangle the full structure from the 2D representation. It just looks like a jumble of lines and colors. The eye slides off it, since we're not in the habit of figuring out how to translate it from the image to the object. Take a look at this molecule. You probably notice the central atom, the three branches, and the way that there's six blue atoms, each with two black atoms, and everything with white atoms.
But did you notice the way each looped branch is twisted relative to the others? Did you see how the angle of the tetrahedrons within each branch is rotated from link to link to link? Those are features that I only picked out when I committed this image to memory. Afterward, they jumped out at me even when I look at the original image. The picture looks different to me than it did before.
If you want to learn, do the real thing. Everybody learns what their job requires them to memorize, what it allows them to reference, and when it's best to consult with an expert. The memorization you'll accomplish by doing the work, not building a memory palace.
School is a signalling system. The smart thing to do is focus on maximizing your grades with minimal effort, not memorizing your gen chem textbook. Real learning is what you do on the job. So you should focus all your efforts on getting the job you want as efficiently as possible, not on this self-gratifying scholasticism. If you're getting tested on your calculations, and admitted to grad school or hired on the basis of your grades, then screw deep learning - start grinding!
I'm hoping the grind-and-graduate perspective is not just sad, but also suboptimal. It might be that memory palaces can be not just a slow and vivid hard drive, but can also allow you to do original thinking, set up calculation schemes, and expand what you're able to learn.
It'll be hard to say what's possible without a lot more practice. But I've never heard any teacher give one iota of guidance on any of this in my life, which makes me think it's probably a neglected topic. Visual thinking ability and imagination is hard to measure even by the standards of psychology and education science, and it's hard to turn into a product. So no wonder. I think it would be valuable just to have some case studies from people in this community who are willing to try it and see what happens.