For thousands of years in cultures all across the world, there has been a fascination with
this tiny little structure in the back of your brain called the pineal gland.
The philosopher Rene Descartes even went as far as to claim it as the "principal
seat of the soul", which is about as lofty of a claim as you can possibly get.
In more modern times it's been associated with the third eye chakra point.
Some even speculate it might be the source of the hormone responsible for dreaming
and near-death experiences.
Again, some pretty lofty claims.
So in today's video we're going to do a deep dive on the pineal gland.
We're going to look at it, and some of the surrounding anatomy.
We're going to discuss its function and see if there's any legitimacy to
all the claims that have been made over the past few thousand years.
Let's do this!
Let's start by taking a look at some of the relevant anatomy so we
can get a good understanding of the exact location of the pineal gland.
So first off, you're looking at a bisected head in
the mid-sagittal plane — so that means it's been cut right down the center.
There is a ton of really interesting anatomy that we can see here, but we're going to be focusing
our attention today in this small portion in the dead center of the head, called the diencephalon.
There are several different structures inside of the diencephalon, so once
again we're going to try and limit our focus to just a couple of areas,
namely this region here that I'm traversing with the probe, called the hypothalamus.
It's called the hypothalamus because it's just below this structure right here,
called the thalamus.
Then right behind the thalamus is going to be this reddish—purple,
tiny little structure, and this ladies and gentlemen, is the pineal gland.
Now the pineal gland is going to be reddish—purple
because it is one of the most vascular tissues in the body.
In fact, it's a rebel!
It's a renegade!
Most of the structures you can see here are going to have what's called the blood—brain
barrier protecting it, which you could think of as kind of like this bouncer,
deciding what kind of substances get to interact with the neurological tissue.
But not the pineal gland!
The pineal gland just has tons and tons and tons
of blood flowing through it and that's what gives it this darkened appearance.
Another thing that's pretty unique about this pineal gland
is that there's really only one of it.
What I mean by that is — if you take a look at all the rest of these neurological structures in here,
there is a left and a right hemisphere to them.
So for instance, you're looking at the left hemisphere of the cerebellum, and then behind this
thick band of connective tissue, called the falx cerebri, is the left hemisphere of the cerebrum.
But not the pineal gland!
There is only one pineal gland — it doesn't have hemispheres.
It's also going to be sitting right dead in the center.
Now this is the primary reason the philosopher Rene Descartes decided — by the way,
Rene Descartes is one of the most influential people in all of philosophy — and he decided
looking at this, he's like... "well if there's two of everything else and only one of this, it
makes a lot of sense that if anywhere in the brain there was going to be the soul, this would be it!"
The thing is, based on our current understanding of neuroscience,
there is no consciousness located here in the pineal gland.
It's glandular.
This is going to secrete things like hormones — not be a storehouse for consciousness.
So, as cool of a thought as that is, I don't think Rene Descartes was correct on that one.
What about the whole "third eye" component to it?
Because in my mind, this is actually super cool.
Because the pineal gland, actually has an indirect connection to your eyeballs.
When light first hits your eyeballs, it's going to go through these curved
structures called the cornea and the lens, and that's going to bend the light to hit
this photoreceptive layer in the very back of your eyeball, called the retina.
The retina is then going to have synapses and send the signals
of that light to this area of the brain right here called the hypothalamus.
But it's a very specific structure on the hypothalamus
that I'm poking with my probe right here, called the suprachiasmatic nucleus.
This is your biological clock.
You see, pretty much every living thing on this planet — that includes plants,
fungus, even you — has what's known as a circadian rhythm.
This is a perception of time,
even at a cellular level, based around a 24-hour period as the earth turns around.
This is so important to health, we're just now realizing how big of an impact
alterations in your circadian rhythm can have in things such as
schizophrenia, cancer, and all sorts of very interesting neurological disorders.
Your circadian rhythm is primarily dictated by melatonin levels.
Melatonin, which is probably familiar to you because you can purchase this in
a bottle at your local grocery store, is a natural sleep aid.
But it is what tells your cells and your body to essentially just start
quieting down — go to sleep.
Guess where we know it's produced at — the pineal gland.
You see, the suprachiasmatic nucleus is going to indirectly connect to the pineal gland, it's going
to send some impulses to various other structures down in the neck and then it's going to come
back up and say, "hey! Pineal gland! Make more melatonin when we're in the presence of darkness!"
You see, it's not even necessarily based around sunlight.
It could be daytime, but you're in a pitch-black room, what that will then tell your pineal gland
through your suprachiasmatic nucleus is, "hey, maybe it's time to go to sleep..."
So what will happen, is in the
lack of light, that is then going to stimulate the pineal gland to create more melatonin.
Again this is something we know for a fact that the pineal gland is going to do.
Maybe it's time we get into speculation land, or conjecture land, or maybe land...
And I don't say that because this is not true,
it's just that we need a lot more evidence before we can say it's definitely true.
I'm mainly talking about the secretion and creation of DMT, or dimethyltryptamine.
Now this is a very psychoactive compound that a lot of people think the pineal gland
is going to secrete during things like dreams and near-death experiences.
The thing is as far as I know, we have next to no evidence of that at all.
As far as I can tell, that's just something people are saying because
it would make sense if that was the case based on what we know about DMT.
But that doesn't mean that we've actually seen that in any kind of laboratory setting.
In fact, we have only found very minimal amounts of DMT
in the brain of humans, and we have found some in rodents like rats, but
that doesn't necessarily mean that it scales correctly or appropriately to humans.
Just because it works in a mammal such as a rat,
does not mean it's going to work the same way in a mammal like a human.
And the small amounts of DMT that have been found in humans
haven't been enough to be psychoactive...
So basically if you're telling me that the pineal gland is going to definitely secrete a
whole bunch of DMT during near-death experiences, I really don't know what you're basing that on...
To me, that's nothing but conjecture.
But again, I'm not saying that it's not true...
In fact, based on what I know about DMT, I would not be surprised at all if that is actually true.
But at this point, we got to stop saying it as though it's factual.
I mean, you could get on the internet right now — you get on YouTube right now
and just find video after video after video of people saying,
"near-death experiences, dreams, all this stuff is caused by DMT!"
And I'm just like, "well... I don't know how you know that..."
So what does it all mean?
Am I saying that it's all just a bunch of hogwash and hooey?
That there's no third-eye component to it, and that
DMT isn't being secreted from it and all that?
Kind of!
I'm not trying to be rude or offensive for any
of you who may be really into this opening up at the third-eye type stuff.
Because I personally find that to be fascinating to discuss and have conversations around.
So I'm not trying to be rude or offensive, but what I do want you
to know, if there's one thing you take away from this entire video, it's that
all the stuff you're hearing in pop culture and metaphysical realms is really just conjecture.
It's just people saying stuff...
And that's fine, again, as long as we're just having interesting conversations about it.
But as far as I can tell none of that is actually grounded in science.
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