Dr. Matt Walker

And also in terms of cost, where you can have high cost, minimal cost, low cost.

I mean, hot bath or a shower is pennies on the dollars.

So I think there are probably two emerging data sets that I've been intrigued by, one of which we've been doing some work on, and it comes back to thermal.

What I failed to mention is not just that you need to warm up to wake up, which you do, but you also need to warm up to REM sleep, but not too much.

If you take an organism or a human being and you strip them of bed sheets and strip them of clothes so they're basically almost au naturel,

If you warm the body up to what we call the thermo-neutral point, so it tends to be, and this sounds extreme and you don't have to do this because you're under sheets and that makes a world of difference.

But if you warm the room to about 30 degrees Celsius,

which gets close to at the surface ambient level for your skin, something that can bring your core body temperature up, back up to operating.

Because I told you when you go, when you're in that deep sleep trigger zone, the middle zone, your core body temperature drops and it drops significantly.

And to wake up, you have to warm up.

But on the journey to warming up, you also have to get to thermoneutrality for you to have REM sleep.

If I keep you too cold, I can reduce the amount of REM sleep.

If I get you too hot, I can impair the amount of REM sleep.

So it's a Goldilocks phenomenon, not too little, not too much, just the right amount.

If I keep you there in terms of your thermal net neutrality, I can boost your REM sleep.

Now that's fiendishly difficult when you're trying to solve that equation as a commercial device, because different people are under different blankets, they run at different hot temperatures, they've got different partner situations.

So you need a closed loop system again.

But it's something that we're very interested in because almost all of the methods that I've described, and you were smart to pick this up, all target deep non-REM sleep.

But we spoke about in the first episode, every stage of sleep is important.

And in subsequent episodes, I'll tell you exactly why REM sleep is so critical.