I found this video about the science of learning how your memory knows where your car is parked. It’s rooted in the hippocampus (the part of the brain shaped like a seahorse), and it maps out the territory around you. Some nerves are associated with boundary understandings, and some lay out a grid (a triangular grid, I note — the same sort of grid that Bucky Fuller, bless his heart, thought was the real coordinate system of the Universe… the notion that the brain actually marks things in a triangular grid is a post of its own someday soon). But this is, of course, about… you guessed it…
Palace of Memory
You see, the visual-spatial parts of your brain are what we call, in shorthand, the “right brain” (even though they’re not all in your right brain). And the “left brain” is more about language and deductive thought, and linear processing of information. We contrast the two hemispheres of the brain by talking about one as more formal and organized (left), and one as more holistic and broad-brush and creative (right). But the hippocampus is neither — it’s in the brain stem, or at least attached to it, and doesn’t really look at the world from either point of view. It’s more raw processing power, and at least some of that processing power is directed at knowing where you are in the world.
When you imagine your own Palace of Memory, though, your forebrain — your left brain and your right brain — are likely pinging a left-brain neuron for the information stored, and a right-brain neuron for the image associated with that stored information, and some grid-neurons and edge-neurons in the hippocampus. You’re engaging four neurons (or possibly neuron-groups) for the price of one memory, and fixing it more completely in your mind.
This is the essence of the ancient technique, which pseudo-Cicero in Ad Herennium called the artificial memory, but which is in fact not artificial at all — it’s apparently rooted in a genuine brain function, and it’s possible to uncover that brain function through science — and then exploit that awareness through a technique of personal development that’s at least 2500 years old. Brilliant.