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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.
that sound good? -yeah gonna take about eight minutes
eight minutes perfect okay
I'm ready when you are
but before we do this let's meet the researchers. Can you
introduce yourself? -introduce myself? ah
my name is Shin Shimojo. I'm a professor
in neuroscience and experimental psychology at here Caltech Biology
Connie you are the first author here and your paper has just been
published, when this video goes out.
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 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
Myy 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 80s Robin 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 a pretty significant results from that.
Shortly afterwards maybe a few years afterwards 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 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 in yes
that's the way you have to crouch in
So I'm gonna 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 a good control over the modified Faraday 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 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 in here
yes -is 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 what happens 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 counter clockwise 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 over all 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 counter clockwise 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 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.
Native speakers of such languages
would refer to a nearby tree as being to their north rather than being in front
of them. 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's one 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 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 this study does not support that.
no it 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 for future research because
you know you can't have any behavior without some kind of something going on
in your brain.