How stress affects your brain - Madhumita Murgia

Kako stres utječe na mozak -Madhumita Murgia

Prevoditelj: Irena Dobrić Recezent: Ivan Stamenković

Are you sleeping restlessly,

Spavate li nemirno,

feeling irritable or moody,

nervozni ste ili mrzovoljni,

forgetting little things,

zaboravljate sitnice,

and feeling overwhelmed and isolated?

osjećate se preopterećeno i izolirano?

Don't worry. We've all been there.

Ne brinite se. Svi smo to prošli.

You're probably just stressed out.

Vjerojatno ste samo pod stresom.

Stress isn't always a bad thing.

Stres nije uvijek loš.

It can be handy for a burst of extra energy and focus,

Može biti koristan jer naglo podiže energiju i koncentraciju,

like when you're playing a competitive sport,

naprimjer kad se bavite natjecateljskim sportom

or have to speak in public.

ili morate govoriti u javnosti.

But when its continuous,

Ali ako ste stalno pod stresom,

the kind most of us face day in and day out,

kao što je to većina nas iz dana u dan,

it actually begins to change your brain.

on počinje mijenjati vaš mozak.

Chronic stress,

Kronični stres,

like being overworked or having arguments at home,

naprimjer premorenost ili obiteljske svađe,

can affect brain size,

može utjecati na veličinu mozga,

its structure,

njegovu građu

and how it functions,

i na njegov način rada,

right down to the level of your genes.

sve do razine gena.

Stress begins with something called

Stres započinje takozvanom

the hypothalamus pituitary adrenal axis,

osovinom hipotalamus - hipofiza - nadbubrežna žlijezda (HPA),

a series of interactions

nizom interakcija između

between endocrine glands in the brain and on the kidney,

endokrinih žlijezda u mozgu i žlijezda na bubregu.

which controls your body's reaction to stress.

koje određuju kako će organizam reagirati na stres.

When your brain detects a stressful situation,

Kad mozak uoči neku stresnu situaciju,

your HPA axis is instantly activated

osovina HPA istog se trena aktivira

and releases a hormone called cortisol, which primes your body for instant action.

i počne lučiti hormon kortizol, koji priprema organizam za brzu reakciju.

But high levels of cortisol over long periods of time

No visoka razina kortizola tijekom dužeg vremenskog razdoblja

wreak havoc on your brain.

stvara pravi kaos u mozgu.

For example, chronic stress increases the activity level

Naprimjer, kronični stres povećava aktivnost

and number of neural connections in the amygdala,

i broj neuronskih veza u amigdali,

your brain's fear center.

centru straha u mozgu.

And as levels of cortisol rise,

I kako razina kortizola raste,

electric signals in your hippocampus,

tako električni signali u hipokampusu,

the part of the brain associated with learning, memories, and stress control,

dijelu mozga koji je povezan s učenjem, sjećanjima i kontrolom stresa,

deteriorate.

postaju sve slabiji.

The hippocampus also inhibits the activity of the HPA axis,

Hipokampus također koči aktivnost osovine HPA

so when it weakens,

i kad se ona smanji,

so does your ability to control your stress.

smanji se i naša sposobnost da kontroliramo stres.

That's not all, though.

No to nije sve.

Cortisol can literally cause your brain to shrink in size.

Pod utjecajem kortizola mozak se može doslovno smanjiti.

Too much of it results in the loss of synaptic connections between neurons

Previše kortizola reducira broj sinapsi među neuronima

and the shrinking of your prefrontal cortex,

i smanjuje prefrontalni korteks,

the part of your brain the regulates behaviors like concentration,

dio mozga koji regulira funkcije kao što je koncentracija,

decision-making,

donošenje odluka,

judgement,

prosuđivanje

and social interaction.

i socijalna interakcija.

It also leads to fewer new brain cells being made in the hippocampus.

Dovodi i do toga da se u hipokampusu stvara manje novih moždanih stanica.

This means chronic stress might make it harder for you to learn

To znači da kronični stres može otežavati učenje

and remember things,

i pamćenje

and also set the stage for more serious mental problems,

te otvoriti put ozbiljnijim psihičkim problemima,

like depression and eventually Alzheimer's disease.

kao što su depresija i s vremenom Alzheimerova bolest.

The effects of stress may filter right down to your brain's DNA.

Utjecaj stresa može se očitovati čak i na molekulama DNK u mozgu.

An experiment showed

Jedan je eksperiment pokazao

that the amount of nurturing a mother rat provides its newborn baby

da briga koju ženka štakora posveti novorođenom mladuncu

plays a part in determining how that baby responds to stress later in life.

utječe na to kako će taj štakor kasnije u životu reagirati na stres.

The pups of nurturing moms turned out less sensitive to stress

Mladunci koji su imali brižnu majku bili su manje osjetljivi na stres

because their brains developed more cortisol receptors,

zato što se u njihovom mozgu razvilo više receptora za kortizol,

which stick to cortisol and dampen the stress response.

koji vežu na sebe kortizol i smanjuju utjecaj stresa.

The pups of negligent moms had the opposite outcome,

Mladunci koji su bili zanemareni doživjeli su suprotan ishod

and so became more sensitive to stress throughout life.

te su postali osjetljiviji na stres, a takvi su ostali cijeli život.

These are considered epigenetic changes,

Takve promjene nazivaju se epigenetskim promjenama,

meaning that they effect which genes are expressed

što znači da utječu na to koji će geni doći do izražaja,

without directly changing the genetic code.

ali ne i na sam genetski kod.

And these changes can be reversed if the moms are swapped.

Te se promjene mogu poništiti ako se majke zamijene.

But there's a surprising result.

No došlo se do iznenađujuće spoznaje.

The epigenetic changes caused by one single mother rat

Epigenetske promjene koje je uzrokovala jedna ženka štakora

were passed down to many generations of rats after her.

naslijedili su mnogi naraštaji štakora nakon nje.

In other words, the results of these actions were inheritable.

Drugim riječima, posljedice njenog ponašanja bile su nasljedne.

It's not all bad news, though.

No nije sve tako crno.

There are many ways to reverse what cortisol does to your stressed brain.

Mnogo je načina da se ponište posljedice djelovanja kortizola na mozak.

The most powerful weapons are exercise and meditation,

Od najveće su koristi tjelovježba i meditacija,

which involves breathing deeply

odnosno duboko disanje

and being aware and focused on your surroundings.

i usredotočenost na ono što nas okružuje.

Both of these activities decrease your stress

Obje aktivnosti smanjuju stres

and increase the size of the hippocampus,

te povećavaju volumen hipokampusa,

thereby improving your memory.

i tako poboljšavaju pamćenje.

So don't feel defeated by the pressures of daily life.

Zato ne dozvolite da vas skrše pritisci svakodnevnog života.

Get in control of your stress before it takes control of you.

Preuzmite kontrolu nad stresom prije nego što on počne kontrolirati vas.