Okay, they’re about to lock me in here and then use these electric coils to make magnetic fields that rotate. They’re roughly the strength of Earth’s magnetic field and we’ll see if my brain is picking up on the fact that the magnetic field is changing. The whole time I’ll have my eyes closed it’ll be pitch black in here, basically no stimuli except for the changing magnetic field and I’ll keep my head perfectly still facing forward.
So what is the setup of the paper how do you set this up? So basically we wanted to see if humans have any brain response to a magnetic field. it has long been recognized that certain bird species have a remarkable ability to find their way home, hence the use of homing pigeons to carry messages for us.
Their impeccable sense of direction is owed in part to their ability to sense the Earth’s magnetic field but they are not the only animals that do this certain bacteria, bees, salmon, turtles rats, dogs, whales, cats in all of them are known to have a magnetic compass. Dogs, known to poop with their bodies oriented preferentially north-south have even been trained to locate bar magnets Given a choice between three containers they were much better than chance at identifying the one containing the magnet.
In fact, they were much better at finding a magnet than finding a food treat under similar conditions Given all these examples it seems more likely that humans should have the ability to detect magnetic fields. And if you’re wondering how humans could physically pick up the magnetic fields, consider that magnetite crystals have been found in the brain that closely resembled those of magnetically active bacteria My colleagues in neuroscience said ‘wow this is hard to believe you know this is impossible’ but lots of biologists and geophysicists said well it’s a matter, of course, humans are not, you know, exceptions among all those mammalian species. But up till now, the evidence has been contradictory and controversial.
So in the early 80sRobin, Baker did some studies where they took groups of students and drove them around in very convoluted routes around the English countryside. And they were blindfolded and then they would stop the bus and ask the students to identify which direction they came from. So basically ‘home’ and they got pretty significant results from that.
Shortly afterward maybe a few years afterward this study was attempted again at Princeton University and they did just a very similar experiment there and they couldn’t get significant behavioral results there. that’s a controversy, lots of positive reports and the failure of the duplication, negative data in neuroscience as well so let’s step back and then see if there’s any systematic, selective response from the brain to the magnetic field itself, not anything associated like a vestibular thing or visual scene, swinging and stuff like that.
So this is the test chamber, I’ll turn on the light so this is um our magnetic… is that the way we get yes that’s the way you have to crouch in So I’m gonna crawl under there.-Yes and you sit down there… hang on a sec hang on this is too cool I really like it.
What.. whose chair is that? It just happened to be…Joe’s chair Joe’s reclining the chair and not used for this purpose but it turned out it’s very relaxing and the main reason of this cage is to shield the outside effect for one thing and also have good control over the modifiedFaraday cage where electricity is running okay, so and then there’s no sound or vision or tactile or any other additional stimulation because we are tapping into the very subtle response of the brain at the subliminal subconscious level.
It doesn’t block the Earth’s magnetic field. The Earth’s magnetic field goes straight through this and that’s actually sort of what we want because inside the chamber we’re not trying to override the Earth’s field we’re just trying to redirect it just to add a little bit of field here and here remove a little bit there and by doing that we can smoothly move the field back and forth and move it in a way that relates to how someone might experience the field as they’re sort of moving you know around outside so that’s essentially what you’re simulating inhere yes -are you’re making it as though my head is swiveling around in the earth’s magnetic field yes except that if you actually doing it in the real world then your vestibular system is also sending signals.
We are not interested in contamination from vestibular signals so we would like to generate artificially that kind of situation like this, however eliminating any other sensory modalities such as vestibular. Can I hop in there and just have a look? oh yeah, go ahead of course – okay I mean I feel like for my job I have been in more weird soundproof boxes than most people These black coils here, do these create the magnetic field? No, so those are for a different experiment so the magnet coils are actually these things.
Those are the magnetic coils And you can see there’s four of these square coils -yeah- in all three directions and this is a nested three-axis coil set and it’s designed to create a magnetic field in any direction inside the chamber and in the center of the chamber where your head and torso is going to be.mm-hmm it’s designed to create a uniform field so a field with no gradients or curves in it.
I’ve brought a compass and so I can just see if the magnetic field is changing, what’s gonna happen when I sit in this room. okay, that was a pretty dramatic shift. So there will be two kinds of rotations one is clockwise and one is counterclockwise and as a control on some trials, the magnetic field won’t change at all. So we can compare on trials that happen after the field rotation versus trials where no field rotated. so this is the sort of thing that I’ll be experiencing but in the dark?
Yep. Now we’re gonna want you to use your left hand to hold it here ’cause it’s easier than the front the cap yep. On this cap, there are 64 electrodes which will pick up the electrical activity of my brain and you’re sure this isn’t just to make people look stupid? – Oh, no, no, no When you’re awake with your eyes closed the dominant signal is called the alpha wave. In most people, it occurs around 10 Hertz. These little squiggles right here they’re happening at around 10 times per second, these are the alpha waves.
We are measuring your alpha wave which is known to be an indicator of relaxing and sometimes even drowsy but not sleeping and then when you notice something like in vision or audition or touch your alpha wave is suppressed and that is the signature of a brain detecting sensory signal and moving attention towards it. So the goal of this experiment is to determine if a magnetic field rotation causes the amplitude of alpha waves to drop. I’m about to go into the cage I’m gonna turn off the light. And then we just do this with a stool turn off all the lights in the room and we close the doors.
And throughout the experiment I’ll be listening in and watching the video for safety reasons Can you hear me? Yes, I can. I’m setting up the experiment. Um, we’ll be starting shortly. Just wait for the ‘ding dings’ The experiment is starting, you can see that’s our starting point. In terms of direction, it will vary from two preset values yeah, so you can see there, that was a field rotation This is like one of the more glamorous ahhhh…there we go. That’s what I was not meant to hit. Thank you. Sorry about that.
I could see that happening. You could see that coming. Man, I was thinking about saying something to the camera. I can’t wait to see the results though. this is a section of my raw EEG results. You can see that every three seconds the field was rotated either clockwise counterclockwise or it was fixed, meaning it didn’t change. Now it’s impossible to draw conclusions just by looking at this so the scientists average overall the trials in the different conditions and plot the alpha power over all the electrodes. This is a recording from someone who is particularly sensitive to changes in the magnetic field.
As I play this, watch how the clockwise and counterclockwise responses compare to the fixed field result. the recording starts before a rotation. The magnetic stimulus takes place and now observe the post-stimulus-response, particularly for counterclockwise for this subject the counterclockwise rotation resulted in a clear decrease in alpha power of at least three decibels shown by the dark blue color. This corresponds to a decrease in alpha power by around 50% Now, here are my results.
After the magnetic stimulus, my response to counterclockwise is clearly not as pronounced. But over time for clockwise rotations, my alpha power is reduced. I was told I was neither the most sensitive to magnetic fields nor the least sensitive, I was somewhere in the middle. So the conclusion is that our brains have the ability to sense magnetic field change but it’s implicit and subliminal it’s non-conscious part of the brain. This is just the first step to make sure that it’s not theoretically impossible that our ancestors might have utilized this ability for their navigation. Even the modem people like ourselves may potentially have it.
This will open up the window for the next stage research as to how we could bring it to the consciousness, how could we strengthen them, and how could we utilize it. As yet it’s unclear if anyone can actually make use of this sense consciously or subconsciously to help them navigate, but the study’s authors point out that a surprising number of human languages lack terms like front back left and right and instead use cardinal directions, North, South, East, and west.
Individuals who’ve been raised from an early age within a linguistic social and spatial framework using cardinal reference cues might have made associative links with geomagnetic sensory cues to aid in daily life. In other words, people from such cultures may be conscious of their magnetoreception. They would be very interesting to test.
But if it turns out that this sense is no longer functional in humans, just a relic from our ancestors, it would be interesting to consider why we lost it. Maybe modern world humans don’t need it – that’sone explanation. Another explanation is we are surrounded so much and exposed so much to artificially created strong magnetic fields, starting from the airplane cabinet, headphones, some younger people are wearing this for 10 hours per day.including an MRI scanner too.
So it’s possible our internal compass may be a victim of our modern technology. This study does not show that magnetic fields have some kind of special influence on you, that they don’t cure disease, they don’t make you smarter. you can’t communicate telepathically or something through them So these are the types of emails that Connie does not want to receive just so, just so everyone’s clear in case you’ve got sort of a crazy idea.
My hair still looks stupid, In case you have a crazy idea for what to do with magnetic fields and the human brain this study does not support that. It only supports that the human brain and pick up on the physical stimulus of the Earth’s magnetic field yup Which, in itself is a super cool finding. it is a super cool finding, it’s like the basis for future research because you know you can’t have any behavior without some kind of something going on in your brain.