these are two sides of the same coin.

You see the color green,

there's something happening in your brain

that's coding that experience of the color green.

So, with psychedelics,

the biggest divide is whether we're talking about

on the psychological side or the biological side.

Does it work by hitting these brain receptors

and then having other effects?

Or does it work because of the experience?

Clearly, there's this very real biological effect.

Something dramatic happens to the brain

when you put the psychedelic in the system,

but then someone has this experience,

and when they change their life because of that,

that ends up sounding more like

they went through a really good course of psychotherapy.

So, psychedelics are really interesting

at that bridge between the biological and the psychological.

What 'psychedelic' means from its linguistic roots

is "mind manifesting."

The idea that these are mind manifesting-

that's consistent with this other notion

that these are non-specific amplifiers.

In other words,

you could have a euphoric experience.

You could have a hellish experience.

Also, terminology is so difficult in this area.

Psychedelic can be used to refer

to what are called the "classic psychedelic compounds":

psilocybin, which is in magic mushrooms,

LSD,

DMT, which is in ayahuasca,

mescaline, which is in peyote.

Those are the classic psychedelics.

They affect a particular type of serotonin receptor

and that's their primary mechanism of action.

But then you have other drugs

that I think it's appropriate to call them psychedelic;

other scientists will disagree.

So for example, MDMA will work by releasing serotonin.

So, that's a different mechanism.

And you have other drugs such as ketamine and PCP.

So, that affects the glutamate system

in the brain primarily rather than the serotonin system.

So, what does psychedelic mean then

if it refers to multiple pharmacological classes of drugs

that work in different ways?

And the answer for me is that these are all drugs

that can have a profound effect on one's sense of reality,

including one's sense of self.

The huge question that's always thrown out is:

'How do these psychedelics work?'

And you can just come at that from so many different angles.

Now to go down that biological path,

what's happening?

There's a lot going on.

For example, psilocybin,

which people may know is the active agent

in so-called "magic mushrooms."

Once it's circulating through your blood,

after you've eaten some of it,

it actually converts to a related compound called psilocin,

which is the thing that's actually hitting

the brain receptors.

And it activates a subtype of serotonin receptor.

So, we have lots

of different types of serotonin receptors in our brain.

One is called the 'serotonin 2A' receptor,

and psilocybin and the other classic psychedelics,

can latch onto that

the same way that our serotonin latches

onto these brain receptors.

So, psilocybin affects serotonin,

but then serotonin affects the glutamate system.

And then at another level,

you have this massive increase in communication,

across these different silos in the brain.

That is probably an important level of analysis

that is underlying at the psychological level:

patients who have claims of insight viewing themselves

from a radically different perspective,

from a different lens,

and based on animal research,

there also seems like there may be

increased 'neuroplasticity'

in the system so that in the days following

the psychedelic experience,

people are more primed to learn new things.

There's a greater ability to establish a new

and more optimal normal state.

So, there's seemed

to really be something important about

'the nature of the experience'

that people have during these sessions.

It's not just about hitting a certain type

of serotonin receptor in the brain.

There's something about the psychology

of the experience that unfolds

during that session that tends to be important-

which is in some sense

what makes the psilocybin treatments,

a bit more like psychotherapy

than traditional psychiatric medications

where you just take the pill and you forget it.

There's some interacting reasons

why the psychedelic renaissance is happening now.

Our society has been in a mental health crisis,

and it's been stagnating.

Pharmaceutical companies don't make the investments

in new mental healthcare treatments,

like they did decades ago.

I mean, the best medical treatments

that we have for many addictions,

are substitution treatments,

also known as 'agonist treatments.'

And I think these are good,

but when you don't see success,

I would say it's probably 'cause they fail

to get to the roots of these mental disorders,

including addiction.

That's why I think psychedelics have been so successful.

Nothing is gonna be a miracle cure for everyone-

nonetheless, they have so much promise,

and we have to have that balance.

I think that's more possible today.

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