[whimsical soft music] NARRATOR: For a lot of people, getting enough sleep can be tough.

New parents, [baby crying] night shift workers, soldiers, [wind billowing] and nearly everyone as we get older.

The ways we have now to improve sleep don't work for everyone.

And sometimes, they come with side effects.

But imagine there was something you could wear to bed that could coax your brain into getting more deep sleep.

Well, that?

[snoring] [wondrous orchestral music] SOPHIA: Measuring out the materials I use.

NARRATOR: Early prototypes of any technology can be a little persnickety.

SOPHIA: Okay.

NARRATOR: Just ask engineer Sophia Fluke.

It's a very delicate process because we just made all of this ourself.

NARRATOR: She loves it, but there's something else there too.

Also, a little bit of hate for it.

It depends on the day.

Let's see how our electrodes look.

NARRATOR: This is the WISP.

I think this guy's ready to use.

NARRATOR: And if all goes as planned, it could change the way we think about sleep.

of biology's greatest mysteries.

We used to think that the need to sleep was something we could minimize or conquer, but really, over the past couple of decades, we've started to understand just how important it is.

Not only the duration of sleep, but now we're increasingly more aware of the need for high quality sleep.

NARRATOR: The WISP is a wearable headband designed to make you feel more rested and alert.

The goal of these Eugene and Portland researchers is to influence a sleep stage known as deep sleep or slow-wave sleep.

These look like the brain is almost trying to get into slow-wave sleep.

The sleep scientists for many years now have long thought that the most restorative phase of sleep is slow-wave sleep.

The sleep that you see usually in the first half of the night as soon as your head hits the pillow.

NARRATOR: This kind of sleep also affects memory.

As you get old, as I can verify, your memory is not as good for all the incidental things that happen during the day.

And there's very good evidence that part of that's because you're losing the capacity for deep sleep.

NARRATOR: Brainwaves are normally chaos.

Neurons fire in different parts of your brain as you talk, move, dream, and solve problems.

It's a purposeful cacophony, but during deep sleep, your brain waves slow down and synchronize, throbbing in slow oscillations.

The WISP picks up on those pulses and applies light electrical stimulation.

MIRANDA: It detects when your brain is naturally entering slow-wave sleep.

And at that exact moment that it sees that, the device will hook onto those and stimulate the brain to make those larger and last longer.

DON: Once we do that, the brain's slow oscillations continue throughout the night.

So it's like we jumpstart the natural rhythms and keep them going.

NARRATOR: The team didn't discover this quirk of neurobiology.

MALE SPEAKER: Keep eyes closed, eyes closed.

NARRATOR: But they've been able to isolate where these slow waves originate and target them.

MALE SPEAKER: Good.

NARRATOR: They've tested WISP on a few people in Oregon so far, and the results are promising, so much so, it caught the attention of the U.S. Military, which recently linked sleep deprivation in soldiers to accidents, traumatic brain injury, PTSD, and suicide.

The military's funding a second round of clinical trials.

That looks like it'll work fine.

See how that goes.

NARRATOR: Which means BEL engineers are busy developing a new prototype that'll be a little more stylish.

Fit, comfort, electrode placement as far as trying to get to the right place on your head.

Well, it thinks it's done.

NARRATOR: It'll be a game changer if the WISP delivers and gives sleep deprived people a better night's rest, but lurking on the edge of this project is science that could be even more exciting.

It involves a part of the brain we didn't really know existed until about a decade ago.

It's called the glymphatic system and it's revolutionizing our understanding of sleep, dementia, and Alzheimer's.

The glymphatic system right now is an enigma.

We know it exists in mice.

We think it exists in people and we have some proof, but we really don't know what it looks like.

We don't know how it functions.

NARRATOR: Scientists think the glymphatic system is a series of canals, pathways.

MALE SPEAKER: It's a series of tubes!

NARRATOR: Its purpose is to flush away all the excess proteins and byproducts the brain makes as it works.

Buildups of some of these proteins not being able to clear them away effectively are thought to play a starring role in the development of Alzheimer's disease.

This way.

NARRATOR: At the University of Washington Medical Center, Rane Levendovszky is working on noninvasive ways to measure the flow of the glymphatic system after a good and bad night's sleep.

SWATI: MRI is my window into their brain.

NARRATOR: In science, if you can't measure something, you can't truly understand it.

SWATI: We are trying to see the system from many different angles, hoping to catch some part of it and then put the pieces of the puzzle together and have a picture of glymphatics for us.

NARRATOR: The WISP trials are the perfect opportunity for this because the synchronized slow waves of deep sleep are when the glymphatic system takes out the most trash.

Okay, are you ready to start?

MALE SPEAKER: Yep.

NARRATOR: If the team's hypothesis holds, disrupting sleep we will disrupt the glymphatic system and improving deep sleep will make it work even better.

It will connect another dot between sleep and memory.

SWATI: If we can make this part of a routine test, once you hit 65, you get an MRI, you do a glymphatic measurement, and you see that your glymphatic system is not working the way it should be, that could be an indication that, okay, you're at risk of Alzheimer's.

And so you can help to at first, maybe slow down the progression of the disease and maybe at some point develop technology or therapy that can just prevent it from tanking at a later stage.

NARRATOR: That better sleep technology may end up looking suspiciously like the WISP headband, improving our sleep tonight and into the future.

DON: Now, one of the questions is, can we keep this up for weeks and months and really change somebody's brain aging process?

Can we make younger brains by helping to synchronize them in the deep sleep?

NARRATOR: And maybe if we sleep better, we'll age better too.

Probably want to get a little closer, a little bit more progress.

Shooting now.

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