Ian Sample

How did you discover this mechanism?

And so this was your big discovery, the glymphatic system.

Essentially, these channels running alongside blood vessels in the brain, which cerebrospinal fluid can flow through and flush out any waste.

But has it actually been observed in the living human brain?

So you and other scientists have pieced together what is going on with the glymphatic system, what it seems to be doing and how it seems to be working.

Tell me what the impact of this discovery has been.

Mike, and over the past five years or so, we've seen further advances in understanding how this system operates, and particularly the role of neurotransmitters in the operation of the glymphatic system.

Can you tell me what the neurotransmitters are doing in our bodies during the day, in our waking hours?

Okay, so when we're awake, these neurotransmitters like dopamine and serotonin are acting individually.

But now we understand that they're doing something surprising when we're asleep.

What's that?

So what you're saying is we have these chemical messengers that have their specific individual roles in how we feel, how we behave when we're awake, but they have this other role when we're sleeping, which is tied into the glymphatic system, which is tied into how our brain behaves.

is clearing out some of this metabolic waste that we've been talking about.

The changes you were talking about, what are they doing in the brain and body while we're sleeping?

What is the consequence of these slow waves of activity?

So when we're sleeping, and specifically it's during non-REM sleep, we fall into this state where the release of these neurotransmitters, these chemicals like serotonin, dopamine, norepinephrine, they're synchronized into slow waves.

And that seems to be driving this kind of pump that moves the cerebrospinal fluid through the brain.

And as it moves through the brain, it's sort of picking up the waste that is accumulating

in the brain.

That's how it all works in a healthy situation.