Brain Maps and Magic

There's a lot to like about Rachel Schwarzlose's book, Brainscapes. She's a funny, smart writer with a well written survey of the latest research into the neurology of the maps scribed into our brains. New tools like PET and fMRI scans have at last given us the tools to actually watch the human mind at work, a microscope for the mind. It's marvelous, complex, and beautiful.

Let's start simple. The primary visual cortex (V1) is a layer of cells across the back of your skull. Some of these cells are essentially a movie screen that capture the nerve impulses from your retina. It's not a perfect match, the image comes through a bit distorted, but this layer of cells replicates what you see in a fairly faithful 2-D projection, before passing it up the chain to more complex processing systems.

Now imagine a magic user who could throw around tiny bits of energy, with a very tight focus. Would such a person be able to create illusions by stimulating their target's V1 circuits? It doesn't seem beyond the bounds of possibility, since folks are already doing lots of interesting things with transcranial magnetic stimulation. Just a little static electricity directed to the right spot might cause a big flash, stimulating all the neurons at once, followed by temporary blindness, as the cells settled back to baseline. It's tempting to contemplate, so I had to give that talent to a character, a simple hedge witch.

A more sophisticated user might be able to project specific images directly into a person's head. Fun to contemplate, but that's some pretty serious ability, there.

The next map in order of complexity might be the primary sensory cortex (S1). Its layout isn't as straightforward as the V1, but it manages to be a recognizable, if highly distorted, map of the body, particularly the skin. The ability to directly stimulate the S1 could allow projecting the sensation of spiders all over one's body, ugh! Combined with the right V1 signals, it could be convincing (and horrifying!). Of course, being able to write directly to S1 would allow direct inducement of pain and pleasure as well, certainly things with a high potential for abuse.

Related to, and overlapping with, the S1 is the primary motor cortex, M1. If you could seize control of the M1, you could march someone around like a marionette, which seems like a pretty ominous power, not something I'd trust most folks with.

These three maps are low level circuits in the brain that feed into a host of higher, more complex circuits to do advanced processing to create the world we experience every day. What they have in common is that all three interact directly with the concrete physical reality outside our bodies.

But we also need to perceive and represent more abstract concepts, like space, time and objects. Schwarzlose spends some time explaining how these primary maps are tied into others that allow for object recognition, locating your body in space, and a sense of the passage of time. These more abstract circuits don't have the simple physical mappings of the V1, S1, and M1, but researchers suspect that we map our body maps into space, and them into time. The concept of the number line, running from left to right (or not), past to future, is powerful in some cultures, while the idea of front to back motion is more prominent in others.

Zapping someone's object map could completely discombobulate the subject, if not permanently, then at least long enough for a quick getaway, since they're suddenly left without the ability to recognize the objects around them.

As Arthur C. Clarke said long ago, "any sufficiently advanced technology is indistinguishable from magic." I think today's explosion of neurological knowledge opens the doors to lots of interesting magic.