A walk through the stages of sleep | Sleeping with Science, a TED series

Sleep is perhaps the single most effective thing

Translator: Jana Macková Reviewer: Zuzana Munzarová Dziaková

Spánok je možno jedna z najefektívnejších činností,

that we can do each and every day

ktorú môžeme vykonávať každý deň,

to reset the health of our brain and our body.

aby sme zresetovali zdravie nášho mozgu i tela.

And by understanding a little bit more about what sleep is,

A tým, že pochopíme, čo to vlastne spánok je,

perhaps we can get the chance to improve both the quantity and the quality

máme možno šancu zlepšiť množstvo aj kvalitu nášho spánku.

of our sleep.

[Sleeping with Science]

[Spánok s vedou]

(Music)

(hudba)

So, exactly what is sleep?

Takže čo je to ten spánok?

Well, sleep, at least in human beings,

Ľudský spánok sa delí na dva hlavné typy.

is subdivided into two main types.

On the one hand, we have non-rapid eye movement sleep,

Jeden typ je pomalý, pokojný spánok,

or non-REM sleep for short.

v skratke non-REM spánok.

But on the other hand,

Ten druhý typ je spánok spojený s rýchlym pohybom očí – REM spánok.

we have rapid eye movement sleep, or REM sleep.

And non-REM sleep has been further subdivided

Non-REM spánok sa ďalej delí do štyroch fáz,

into four separate stages,

unimaginatively called stages one through four,

neoriginálne nazvanými fáza jedna až štyri,

increasing in their depth of sleep.

pričom v každej fáze sa spánok prehlbuje.

And as we go into those light stages of non-REM sleep,

V ľahkej fáze non-REM spánku sa tep nášho srdca spomaľuje,

your heart rate starts to decrease,

your body temperature starts to drop

teplota nášho tela začína klesať

and your electrical brain wave activity starts to slow down.

a aktivita elektrických vĺn v našom mozgu sa znižuje.

But as we move into deeper non-rapid eye movement sleep,

Počas hlbších fáz non-REM spánku, fáza tri a štyri,

stages three and four,

now all of a sudden the brain erupts

v našom mozgu zrazu „vybuchnú“ veľké, silné mozgové vlny.

with these huge, big, powerful brain waves.

The body is actually recharged in terms of its immune system.

Imunitný systém nášho tela sa dobíja.

We also get this beautiful overhaul of our cardiovascular system.

Telo dôkladne prezrie náš kardiovaskulárny systém.

And, in fact, upstairs in the brain,

A v skutočnosti, hore v mozgu,

deep non-REM sleep will help consolidate memories

hlboký non-REM spánok pomáha konsolidovať naše spomienky

a fixuje ich do nervovej stavby nášho mozgu.

and fixate them into the neural architecture of the brain.

So that's non-REM sleep.

To by bolo k non-REM spánku.

But let's come on to REM sleep,

Teraz sa pozrime na REM spánok, ktorý je druhým hlavným typom.

which is the other main type of sleep.

And it's during REM sleep when we principally have the most vivid,

Práve počas REM spánku mávame tie najživšie

the most hallucinogenic types of dreams.

a veľmi halucinogénne sny.

The brain wave activity actually starts to speed up again.

Aktivita mozgových vĺn sa znova začína zrýchľovať.

It's during REM sleep that we receive almost a form of emotional first aid.

REM spánok je pre nás niečo ako emocionálna prvá pomoc.

And it's also during REM sleep where we get a boost for creativity,

Taktiež zvyšuje kreativitu, vďaka ktorej si vieme spojiť informácie.

that it stitches information together

so that we wake up with solutions

Takže, keď sa ráno zobudíme,

to previously difficult problems that we were facing.

dokážeme vyriešiť zložité problémy, ktorým čelíme.

Coming back to these two types of sleep,

Keď hovoríme o týchto dvoch typoch spánku,

it turns out that non-REM and REM will play out

ukázalo sa, že non-REM a REM spánok

in a battle for brain domination throughout the night,

sa počas noci bijú o nadvládu nad mozgom.

and that cerebral war is going to be won and lost

Každých 90 minút túto vojnu jeden z nich vyhrá,

every 90 minutes,

and then it's going to be replayed every 90 minutes.

no po týchto 90 minútach sa celý boj zopakuje.

And what this produces is a standard cycling architecture of human sleep,

A to vytvára štandardnú cyklickú stavbu ľudského spánku,

a standard 90-minute cycle.

štandardný 90-minútový cyklus.

But what's different, however,

Rozdiel je však v tom,

is that the ratio of non-REM to REM within those 90-minute cycles

že pomer non-REM a REM spánku sa počas 90-minútového cyklu

changes as we move across the night,

mení v priebehu noci.

such that in the first half the night,

V prvej polovici noci väčšina 90-minútového cyklu

the majority of those 90-minute cycles

are comprised of lots of deep non-REM sleep,

pozostáva z hlbokého non-REM spánku, presnejšie fáza tri a štyri.

particularly stages three and four of non-REM sleep.

But as we push through to the second half of the night,

No ako postupujeme do druhej polovice noci,

now that seesaw balance actually shifts over,

hojdačka sa prehupne a väčšina 90-minútového cyklu

and instead, most of those 90-minute cycles

are comprised of a lot more rapid eye movement sleep, or dream sleep,

pozostáva z REM spánku, kedy snívame,

as well as stage-two non-REM sleep,

a z druhého štádia non-REM spánku, ktorý je jeho ľahšou formou.

that lighter form of non-REM sleep.

And it turns out that there are implications

A ukázalo sa, že pochopenie rozčlenenia spánku

for understanding how sleep is structured in this way.

uvedeným spôsobom, má svoje dôsledky.

Let's take someone who typically goes to bed at 10pm,

Predstavme si niekoho, kto pravidelne chodí spať o desiatej večer

and they wake up at 6am,

a ráno vstáva o šiestej, takže spí osem hodín.

so they have an eight-hour sleep window.

But this morning, they have to wake up early

No v jedno ráno musí vstať veľmi skoro,

for an early morning meeting,

pretože má pracovné stretnutie alebo chce naštartovať deň v posilňovni.

or they want to get a jump start on the day

to get to the gym.

And as a consequence, they have to wake up at 4am in the morning,

A preto musí vstať o štvrtej ráno, nie o šiestej.

rather than 6am in the morning.

How much sleep have they actually lost?

O koľko spánku vlastne príde?

Two hours out of an eight-hour night of sleep

Dve hodiny z ôsmich znamená, že príde o 25 percent spánku.

means that they've lost 25 percent of their sleep.

Well, yes and no.

Áno, ale aj nie.

They have lost 25 percent of all of their sleep,

Príde o 25 percent z celkového spánku,

but because REM sleep comes mostly in the second half of the night

no pretože REM spánok je aktívny hlavne v druhej polovici noci,

and particularly in those last few hours,

presnejšie počas posledných pár hodín,

they may have lost perhaps 50, 60, maybe even 70 percent

pravdepodobne príde o 50, 60, dokonca 70 percent

of all of their REM sleep.

z celkového REM spánku.

So there are real consequences to understanding what sleep is

Pochopenie toho, čo je spánok a ako je štruktúrovaný,

and how sleep is structured.

má teda skutočne výhody.

And we'll learn all about the benefits of these different stages of sleep

V ďalších epizódach sa dozvieme o benefitoch rôznych fáz spánku

and the detriments that happen when we don't get enough of them

a o škodách, ktoré spôsobuje ich nedostatok.

in subsequent episodes.