Could the root of Alzheimer's be...magnetic?
I learned about how induction works in school, but I don't think I really understood it until the advent of wireless charging. Practically, it's quite simple: you coil a wire into a loop, connect it to electricity, and a magnetic field forms through the middle of the loop. If you put another non-electrified loop close to that one, the magnetic field from the first one will "induce" a current in the second one. Wireless charging!
It wasn't until years later that I had the thought that this effect might have something to do with consciousness. I had come to the conclusion that there must be a feedback loop in the brain - we, as humans, are constantly making predictions and trying to confirm them. On a very low level, we're predicting and confirming things all the time. You do it unconsciously. I can type 1+1= and make the answer appear in your brain without saying it. So, there must be a feedback loop. It's how we learn after all - Prediction -> True/False -> Prediction -> True/False.
My first thought in this direction was just "consciousness is weird + a loop would generate a magnetic field that might induce currents in neighboring neurons = maybe consciousness is related to that magnetic field". Nothing extraordinary.
A few more years pass.
I'd been thinking consciousness has these weird levels to it. I think the strangest thing that I couldn't quite reason about was the blackouts that we have. Everyone has them. You drive/walk/bike on autopilot to the completely wrong destination, only noticing once you've arrived. Who was driving? How do we do that, seemingly while "unconscious" to the extent that we're not fully aware of what we're doing? How often are we doing that? We're kind of blissfully unaware of our lack of awareness (until we arrive at the wrong destination!) so it might not be uncommon.
I had a bigger thought. What if consciousness is specific to learning?
When you think about evolutionary incentives, it would make sense for our brain to be as fast as possible. "Gut instinct" in that sense should be as automatic as possible. We shouldn't have to consciously think to run away from a charging rhino. Our brains do that automatically. This idea of "thinking fast and thinking slow" isn't novel, but connecting it to "level of consciousness" struck me as a pretty interesting idea. Thinking fast = unconscious running of the brain "model" in a sense - inference. Thinking slow = conscious training of the brain "model", running inference but checking/validating/updating in realtime. Slower and more precise.
That felt right, so I kept thinking about it.
There's a lot of research behind the idea that we don't perceive things in real-time - conscious perception actually lags response time. So like, we've done brain scans on people while they react to something in real time, and their reactions to the stimulus come earlier than the electrical activity that we associate with conscious perception in the brain. So their brain is reacting without consciousness, but then oddly booting up consciousness after that reaction starts. Weird!
But wait, maybe that makes sense. If consciousness is for learning, maybe the primary purpose is feedback on actions. Kind of how AI models are often trained with RLHF, or Reinforcement Learning with Human Feedback. Perhaps the brain is like Reinforcement Learning with Conscious Feedback. So the brain in its current state will act or react according to what you've learned to date automatically, to reduce latency, because that was evolutionarily critical. But once it does, you can evaluate that action/reaction and decide if it was correct or incorrect. So consciousness is in control - we decide how the model is trained, but we aren't the model itself. Hmm.
A few months pass.
I read a paper on consciousness that felt like it was missing the point, and it inspired me to do some digging back into that magnetic field theory. I thought it would be difficult to try to track down a physical loop in the brain responsible for learning, but turns out it's actually pretty established science. Two parts of the brain located at the exact center, connecting the brainstem to the brain, are the thalamus and the neocortex. Connecting them is a tight bidirectional feedback loop called the Cortico-Thalamo-Corticol (CTC) neural circuit. And guess what? If it's damaged, we lose consciousness. Maybe we're onto something here.
Okay, so let's carry that. Let's say this complex feedback loop system at the center of the brain is projecting a magnetic field. That feels right - we know brainwaves exist, and they change depending on our level of consciousness - your brain waves when you're asleep are measurably different than when you're awake. So it's not a crazy leap to assume a magnetic field is connected to conscious perception. But, how? How would a magnetic field actually make an impact on brain function?
This is where it gets weird.
Magnetite is one of the main iron ores that exists, and it's...magnetic. Shocker. But the crazy thing about magnetite is that our brains synthesize it. Yes, our brains synthesize magnetic particles. This sounds insane, but it's less insane than you'd think. Some species of bees and birds famously navigate using biological magnets, and very strangely cows tend to align with the earth's magnetic field when grazing in a field - unless they're near high voltage electrical wires. So magnets in the brain is not unusual for life on earth.
But so, our brains literally make this stuff. Why? We're not totally sure yet. But I have an idea.
Perhaps the magnetic field(s) projected by the CTC loops are able to make small changes to neural circuits in the entire brain by manipulating these magnetite particles that have been synthesized by the body. After all, we know neurons run on electricity, and being able to manipulate conductive magnetic particles could allow us to tweak firing neurons "in-flight". With the source sensory data coming into the thalamus in hand (assuming that's where our conscious perception originates), we could make little corrections to how the brain responds to that data as it responds, thereby strengthening the associated neurons, and making that pathway more likely for the next run - learning, in essence.
But I still wasn't totally convinced. I needed some empirical evidence, and I don't have any spare brains lying around.
A few weeks pass.
Alzheimer's. My grandfather had it. Everyone knows someone who's been affected by it. Terrible disease. I think about it a lot because it's so weird. The way the brain can jump around to different time periods, remember things that never happened, and briefly become lucid even in extremely late stage. It just doesn't feel like a normal disease to me. It feels like a misfiring engine. The brain loses the ability to coordinate itself - it stops understanding the flow of time. Some of the symptoms are as if the "unity of consciousness" has broken apart - sensory data streams are no longer aligning so nothing really makes any sense. But then you get these moments of lucidity. How could a system in such a broken state occasionally just start working again?
I recently started thinking the disease might have something to do with consciousness. I wasn't sure what, but it seemed connected.
As it turns out, there's a hell of a smoking gun here. Back in 2016 researchers discovered there were two types of magnetite in the brain - some biogenic, but most of it originating externally from air pollution - largely created by things like brakes on cars. We're able to tell the difference between the two because the biogenic magnetite is shaped differently - typically octahedral with well defined faces. External magnetite isn't like this - it's typically spherical and irregular in shape.
In the last few years, we've gotten results in empirical studies that magnetite from air pollution leads to signs of Alzheimer's. We'd previously correlated Alzheimer's with high levels of magnetite in the brain, but from what I can tell the research to determine a causation is fairly recent.
What if the disease is a disease of consciousness? What if our magnetic control system starts breaking down as a result of magnetic particles of odd shapes and sizes in our brain reducing our ability to exert conscious control over our brain? Some brains had a 100-1 ratio of external particles. I'd imagine that might cause some chaos.
Addendum: Dopamine binds to magnetite and makes it less likely to clump together. We could this effect in medical technology for all sorts of things, so it's being researched quite a lot. Perhaps amphetamines help with focus because the additional dopamine gives you more precise control over these magnetite particles and thus control over how your neurons fire - allowing you to resist instincts (existing pathways) in favor of new ones. Focus.