Dr. Matt Walker

And despite one continuing on,

you can start to feel better because the other has come to your rescue.

And that shows me that your circadian rhythm doesn't care about how much adenosine is in your brain.

It's just going to keep going up and down, up and down every 24 hours.

And your adenosine level doesn't really care much about your circadian rhythm.

It's going to just build and build and build the longer and longer that you're awake and then get dissipated whenever it is that you sleep.

It does, but in the brain, it has this very interesting influence.

Now, I've described it as making you sleepier, and it does.

That's exactly what it does.

But it does it in a very...

very interesting way.

It's a bi-directional way.

There are at least two different adenosine receptors or adenosine welcome sites within the brain.

And adenosine is very clever in how it makes you sleepy.

Adenosine as it's rising will turn down the volume on the wake promoting regions of your brain.

but yet it will increase the volume on your sleep promoting regions.

And by way of this dual action, that's how it seems to instigate this feeling of sleepiness, by tamping, putting the brakes on wakefulness, but hitting the accelerator pedal on sleepiness.

But then adenosine seems to be part, or one of the reasons that it builds up is because it's a metabolic byproduct of cellular activity, of cellular metabolism.

And it seems to be that the longer that we're awake, because our brain is very cerebrally active during the day, even though I told you that the brain state of sleep is very active, it is, it's a very metabolically active state of sleep.

It is less metabolically active, however, during deep non-REM sleep.