TED2012
Tali Sharot: The optimism bias
Tali Sharot: Sklonost optimizmu
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Jesmo li rođeni da budemo optimistični, a ne realistični? Tali Sharot govori o novom istraživanju koje sugerira da je naš mozak "ugođen" tako da promatramo stvari s vedrije strane te kako to može biti i opasno i korisno.
Tali Sharot - Cognitive neuroscientist
Tali Sharot studies why our brains are biased toward optimism. Full bio
Tali Sharot studies why our brains are biased toward optimism. Full bio
Double-click the English transcript below to play the video.
00:16
I'm going to talk to you about optimism --
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Govorit ću vam o optimizmu --
00:19
or more precisely, the optimism bias.
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ili, preciznije rečeno, o sklonosti optimizmu.
00:21
It's a cognitive illusion
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To je kognitivna iluzija
00:23
that we've been studying in my lab for the past few years,
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koju smo proučavali u mom laboratoriju
nekoliko proteklih godina.
nekoliko proteklih godina.
00:26
and 80 percent of us have it.
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i koju ima 80 posto svih nas.
00:28
It's our tendency to overestimate
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To je naša sklonost precjenjivanju vjerojatnosti
00:30
our likelihood of experiencing good events in our lives
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da ćemo doživjeti dobre događaje u našim životima
00:33
and underestimate our likelihood of experiencing bad events.
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i podcjenjivanju vjerojatnosti da ćemo doživjeti loše događaje.
00:37
So we underestimate our likelihood of suffering from cancer,
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Dakle podcjenjujemo vjerojatnost da ćemo oboljeti od raka
00:40
being in a car accident.
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ili doživjeti prometnu nezgodu.
00:42
We overestimate our longevity, our career prospects.
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Precjenjujemo našu dugovječnost, naš napredak u karijeri.
00:45
In short, we're more optimistic than realistic,
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Ukratko, više smo optimistični, nego realistični,
00:48
but we are oblivious to the fact.
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ali nismo svjesni toga.
00:51
Take marriage for example.
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Uzmite brak za primjer.
00:53
In the Western world, divorce rates are about 40 percent.
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U zapadnom svijetu, stopa razvoda je oko 40 posto.
00:56
That means that out of five married couples,
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To znači da će dva od pet brakova
01:00
two will end up splitting their assets.
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završiti dijeljenjem imovine.
01:03
But when you ask newlyweds about their own likelihood of divorce,
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No kada upitate mladence o vjerojatnosti raspada njihovog braka,
01:06
they estimate it at zero percent.
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oni je procjenjuju s nula posto.
01:10
And even divorce lawyers, who should really know better,
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Čak i odvjetnici za brakorazvodne parnice,
koji bi trebali znati bolje,
koji bi trebali znati bolje,
01:13
hugely underestimate their own likelihood of divorce.
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uvelike podcjenjuju vjerojatnost raspada vlastitog braka.
01:17
So it turns out that optimists are not less likely to divorce,
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Dakle ispostavlja se da za optimiste nije manja vjerojatnost da će se razvesti,
01:20
but they are more likely to remarry.
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ali je veća vjerojatnost da će ponovo stupiti u brak.
01:23
In the words of Samuel Johnson,
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Riječima Samuela Johnsona,
01:25
"Remarriage is the triumph of hope over experience."
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"Ponovno stupanje u brak je pobjeda nade nad iskustvom."
01:29
(Laughter)
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(Smijeh)
01:31
So if we're married, we're more likely to have kids.
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Ako smo u braku, veća je vjerojatnost da ćemo imati djecu.
01:36
And we all think our kids will be especially talented.
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I svi mislimo kako će naša djeca biti posebno nadarena.
01:39
This, by the way, is my two-year-old nephew, Guy.
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Ovo je, usput rečeno, moj dvogodišnji nećak Guy.
01:42
And I just want to make it absolutely clear
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I želim samo naglasiti
01:44
that he's a really bad example of the optimism bias,
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da je on uistinu loš primjer sklonosti optimizmu,
01:47
because he is in fact uniquely talented.
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jer je on stvarno iznimno nadaren.
01:50
(Laughter)
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(Smijeh)
01:51
And I'm not alone.
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I ja nisam jedina koja ovako razmišlja.
01:53
Out of four British people, three said
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Troje od četvoro Britanaca su rekli
01:55
that they were optimistic about the future of their own families.
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kako su optimistični u vezi budućnosti svojih obitelji.
01:59
That's 75 percent.
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To je 75 posto.
02:01
But only 30 percent said
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Ali samo 30 posto ih je reklo
02:03
that they thought families in general
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kako misle da je obiteljima, općenito govoreći,
02:05
are doing better than a few generations ago.
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bolje nego što je bilo prije nekoliko generacija.
02:08
And this is a really important point,
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Ovo je vrlo važno istaknuti
02:10
because we're optimistic about ourselves,
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zato što pokazuje da smo optimistični u vezi nas samih,
02:11
we're optimistic about our kids,
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optimistični smo u vezi naše djece,
02:13
we're optimistic about our families,
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optimistični smo u vezi naših obitelji,
02:15
but we're not so optimistic about the guy sitting next to us,
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ali nismo toliko optimistični kada se radi o drugima,
02:18
and we're somewhat pessimistic
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i donekle smo pesimistični
02:20
about the fate of our fellow citizens and the fate of our country.
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kada se radi o sudbini naših sugrađana i sudbini naše države.
02:24
But private optimism about our own personal future
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No privatni optimizam o našoj osobnoj budućnosti
02:28
remains persistent.
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ostaje trajan.
02:30
And it doesn't mean that we think things will magically turn out okay,
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To ne znači kako mislimo
da će se stvari magično posložiti,
da će se stvari magično posložiti,
02:34
but rather that we have the unique ability to make it so.
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već da imamo jedinstvenu sposobnost da to ostvarimo.
02:39
Now I'm a scientist, I do experiments.
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Ja sam znanstvenica i provodim pokuse.
02:41
So to show you what I mean,
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Kako bih vam pokazala o čemu govorim,
02:43
I'm going to do an experiment here with you.
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provest ću jedan pokus s vama.
02:46
So I'm going to give you a list of abilities and characteristics,
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Dat ću vam popis vještina i karakteristika
02:50
and I want you to think for each of these abilities
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i želim da za svaku od navedenih vještina promislite
02:53
where you stand relative to the rest of the population.
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gdje se nalazite u odnosu na ostatak populacije.
02:57
The first one is getting along well with others.
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Prva je slaganje s drugim ljudima.
03:01
Who here believes they're at the bottom 25 percent?
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Tko ovdje vjeruje da se nalazi u donjih 25 posto?
03:07
Okay, that's about 10 people out of 1,500.
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U redu, to je oko 10 ljudi od 1.500.
03:11
Who believes they're at the top 25 percent?
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Tko vjeruje da se nalazi u gornjih 25 posto?
03:15
That's most of us here.
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Većina nas.
03:18
Okay, now do the same for your driving ability.
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U redu, sad napravite isto za vašu vještinu vožnje.
03:22
How interesting are you?
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Koliko smatrate da ste zanimljivi?
03:25
How attractive are you?
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Koliko ste privlačni?
03:28
How honest are you?
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Koliko ste iskreni?
03:31
And finally, how modest are you?
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I naposljetku, koliko ste skromni?
03:36
So most of us put ourselves above average
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Dakle većina nas sebe svrstava iznad prosjeka
03:39
on most of these abilities.
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vezano za većinu navedenih vještina.
03:41
Now this is statistically impossible.
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To je statistički nemoguće.
03:43
We can't all be better than everyone else.
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Ne možemo svi biti bolji od svih drugih.
03:46
(Laughter)
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(Smijeh)
03:48
But if we believe we're better than the other guy,
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No ako vjerujemo da smo bolji od onog drugog
03:50
well that means that we're more likely to get that promotion, to remain married,
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to znači da imamo veću vjerojatnost da dobijemo promaknuće, da ostanemo u braku,
03:54
because we're more social, more interesting.
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jer smo društveniji i zanimljiviji.
03:57
And it's a global phenomenon.
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Ovo je globalni fenomen.
03:59
The optimism bias has been observed
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Sklonost optimizmu je primjećena
04:02
in many different countries --
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u mnogim zemljama --
04:03
in Western cultures, in non-Western cultures,
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u zapadnim kulturama, u ne-zapadnim kulturama,
04:06
in females and males,
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kod žena i kod muškaraca,
04:08
in kids, in the elderly.
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kod djece i starijih.
04:10
It's quite widespread.
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Poprilično je raširena.
04:11
But the question is, is it good for us?
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No pitanje je, je li to dobro za nas?
04:15
So some people say no.
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Neki kažu da nije.
04:17
Some people say the secret to happiness
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Neki kažu da se tajna sreće nalazi
04:20
is low expectations.
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u niskim očekivanjima.
04:23
I think the logic goes something like this:
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Mislim da je logika iza toga otprilike ova:
04:25
If we don't expect greatness,
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Ako ne očekujemo velike stvari,
04:27
if we don't expect to find love and be healthy and successful,
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ako ne očekujemo da ćemo pronaći ljubav
i biti zdravi i uspješni,
i biti zdravi i uspješni,
04:31
well we're not going to be disappointed when these things don't happen.
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onda nećemo biti razočarani kada se te stvari ne dogode.
04:34
And if we're not disappointed when good things don't happen,
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Ako nismo razočarani kada se dobre stvari ne dogode,
04:38
and we're pleasantly surprised when they do,
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a ugodno smo iznenađeni kada se dogode,
04:40
we will be happy.
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bit ćemo sretni.
04:42
So it's a very good theory,
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Ovo je jako dobra teorija,
04:43
but it turns out to be wrong for three reasons.
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ali ispostavlja se kako je pogrešna iz tri razloga.
04:46
Number one: Whatever happens, whether you succeed or you fail,
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Prvi razlog: što god se dogodi, bilo da uspijete ili podbacite,
04:51
people with high expectations always feel better.
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osobe s visokim očekivanjima se uvijek osjećaju bolje.
04:55
Because how we feel when we get dumped or win employee of the month
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To je zato što naši osjećaji kada nas partner ostavi ili kada postanemo zaposlenik mjeseca
04:59
depends on how we interpret that event.
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ovise o tome kako tumačimo taj događaj.
05:02
The psychologists Margaret Marshall and John Brown
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Psiholozi Margaret Marshall i John Brown
05:06
studied students with high and low expectations.
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su proučavali studente s visokim i niskim očekivanjima.
05:09
And they found that when people with high expectations succeed,
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I utvrdili su da kada ljudi s visokim očekivanjima postignu uspjeh,
05:13
they attribute that success to their own traits.
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oni taj uspjeh pripisuju vlastitim osobinama.
05:16
"I'm a genius, therefore I got an A,
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"Ja sam genije i zato sam dobio peticu
05:18
therefore I'll get an A again and again in the future."
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i zato ću nastaviti dobijati petice i ubuduće."
05:21
When they failed, it wasn't because they were dumb,
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Kada bi doživjeli neuspjeh, to nije bilo zato što su glupi,
05:24
but because the exam just happened to be unfair.
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već zato što je ispit taj put bio nepravedan.
05:27
Next time they will do better.
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Idući put će biti bolje.
05:29
People with low expectations do the opposite.
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Ljudi s niskim očekivanjima čine suprotno.
05:32
So when they failed it was because they were dumb,
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Tako da kada oni dožive neuspjeh to je zato što su glupi,
05:35
and when they succeeded
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a kada postignu uspjeh
05:37
it was because the exam just happened to be really easy.
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to je zato što je ispit taj put bio uistinu lagan.
05:40
Next time reality would catch up with them.
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Idući put će ih stvarnost sustići.
05:42
So they felt worse.
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Stoga se osjećaju lošije.
05:44
Number two: Regardless of the outcome,
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Drugi razlog: bez obzira na ishod,
05:48
the pure act of anticipation makes us happy.
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sam čin iščekivanja nas čini sretnima.
05:52
The behavioral economist George Lowenstein
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Bihevioralni ekonomist George Lowenstein
05:55
asked students in his university
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je zamolio studente sa svog sveučilišta
05:57
to imagine getting a passionate kiss from a celebrity, any celebrity.
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da zamisle strastveni poljubac s bilo kojom slavnom osobom.
06:01
Then he said, "How much are you willing to pay
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Zatim ih je pitao: "Koliko ste voljni platiti
06:04
to get a kiss from a celebrity
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za poljubac slavne osobe
06:06
if the kiss was delivered immediately,
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ako će vas poljubiti odmah,
06:08
in three hours, in 24 hours, in three days,
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za tri sata, za 24 sata, za tri dana,
06:13
in one year, in 10 years?
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za godinu dana ili za 10 godina?
06:15
He found that the students were willing to pay the most
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Otkrio je da su studenti najspremniji najviše platiti
06:19
not to get a kiss immediately,
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za poljubac koji neće dobiti odmah,
06:21
but to get a kiss in three days.
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već za tri dana.
06:24
They were willing to pay extra in order to wait.
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Bili su spremni platiti više da bi čekali.
06:28
Now they weren't willing to wait a year or 10 years;
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Nisu, doduše, bili spremni čekati godinu dana ili 10 godina;
06:31
no one wants an aging celebrity.
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nitko ne želi ostarjelu zvijezdu.
06:32
But three days seemed to be the optimum amount.
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No tri dana se činilo idealnim razdobljem.
06:37
So why is that?
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Zašto je tako?
06:39
Well if you get the kiss now, it's over and done with.
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Zato što ako dobijete poljubac odmah, on je već povijest.
06:43
But if you get the kiss in three days,
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No ako dobijete poljubac za tri dana,
06:45
well that's three days of jittery anticipation, the thrill of the wait.
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onda ćete provesti tri dana u slatkom i uzbudljivom iščekivanju.
06:49
The students wanted that time
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Studenti su željeli to vrijeme
06:51
to imagine where is it going to happen,
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kako bi zamišljali gdje će se to dogoditi
06:53
how is it going to happen.
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i kako će se dogoditi.
06:55
Anticipation made them happy.
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Iščekivanje ih je činilo sretnima.
06:57
This is, by the way, why people prefer Friday to Sunday.
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Ovo je, usput rečeno, razlog zašto ljudi više vole petak nego nedjelju.
07:01
It's a really curious fact,
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To je uistinu neobična činjenica
07:03
because Friday is a day of work and Sunday is a day of pleasure,
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s obzirom da je petak radni dan dok je nedjelja dan odmora
07:06
so you'd assume that people will prefer Sunday,
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pa biste pretpostavili da ljudi više vole nedjelju.
07:09
but they don't.
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No nije tako.
07:11
It's not because they really, really like being in the office
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Ne zato što stvarno vole biti u uredu
07:14
and they can't stand strolling in the park
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i ne podnose šetnje parkom
07:16
or having a lazy brunch.
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ili kasne doručke.
07:17
We know that, because when you ask people
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To znamo zato što kad upitate ljude
07:20
about their ultimate favorite day of the week,
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koji im je najdraži dan u tjednu,
07:22
surprise, surprise, Saturday comes in at first,
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gle čuda, subota je na prvom mjestu,
07:25
then Friday, then Sunday.
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zatim petak pa onda nedjelja.
07:28
People prefer Friday
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Ljudi više vole petak
07:30
because Friday brings with it the anticipation of the weekend ahead,
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zato što petak uključuje iščekivanje predstojećeg vikenda
07:34
all the plans that you have.
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i svih planova za vikend.
07:36
On Sunday, the only thing you can look forward to
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Jedina stvar kojoj se možete radovati nedjeljom
07:38
is the work week.
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je radni dan.
07:41
So optimists are people who expect more kisses in their future,
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Optimisti su dakle ljudi koji očekuju više poljubaca u budućnosti
07:46
more strolls in the park.
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i više šetnji parkom.
07:48
And that anticipation enhances their wellbeing.
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I to iščekivanje pojačava njihovo zadovoljstvo.
07:51
In fact, without the optimism bias,
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Zapravo bismo, bez sklonosti optimizmu,
07:54
we would all be slightly depressed.
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svi mi bili blago depresivni.
07:57
People with mild depression,
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Osobe s blagom depresijom
07:59
they don't have a bias when they look into the future.
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nemaju sklonost optimizmu kada razmišljaju o budućnosti.
08:02
They're actually more realistic than healthy individuals.
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Oni su zapravo realniji od zdravih pojedinaca.
08:07
But individuals with severe depression,
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No pojedinci koji pate od ozbiljne depresije
08:09
they have a pessimistic bias.
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imaju sklonost pesimizmu.
08:11
So they tend to expect the future
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Stoga zamišljaju da će budućnost
08:13
to be worse than it ends up being.
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biti lošija no što na kraju stvarno ispadne.
08:15
So optimism changes subjective reality.
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Dakle optimizam mijenja subjektivnu stvarnost.
08:19
The way we expect the world to be changes the way we see it.
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Naša očekivanja kako će svijet izgledati mijenjaju način na koji ga promatramo.
08:22
But it also changes objective reality.
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No također mijenjaju i objektivnu stvarnost.
08:26
It acts as a self-fulfilling prophecy.
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Ona djeluju kao samoispunjavajuće proročanstvo.
08:28
And that is the third reason
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I to je treći razlog
08:31
why lowering your expectations will not make you happy.
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zašto vas smanjivanje očekivanja neće usrećiti.
08:34
Controlled experiments have shown
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Kontrolirani pokusi su pokazali
08:36
that optimism is not only related to success,
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da optimizam nije samo povezan s uspjehom,
08:38
it leads to success.
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već i da vodi uspjehu.
08:40
Optimism leads to success in academia and sports and politics.
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Optimizam vodi uspjehu u akademskoj zajednici i sportu i politici.
08:45
And maybe the most surprising benefit of optimism is health.
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Jedna od koristi optimizma koja možda najviše začuđuje, jest zdravlje.
08:50
If we expect the future to be bright,
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Ako očekujemo da će budućnost biti svijetla,
08:53
stress and anxiety are reduced.
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stres i tjeskoba se smanjuju.
08:56
So all in all, optimism has lots of benefits.
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Tako da sve u svemu, optimizam ima puno prednosti.
09:00
But the question that was really confusing to me was,
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No ono što me uistinu zbunjivalo
09:03
how do we maintain optimism in the face of reality?
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jest pitanje kako zadržavamo optimizam kad smo suočeni sa stvarnošću?
09:08
As an neuroscientist, this was especially confusing,
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Kao neuroznanstveniku, ovo je bilo posebno zbunjujuće
09:11
because according to all the theories out there,
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je, prema svim raspoloživim teorijama,
09:13
when your expectations are not met, you should alter them.
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kada očekivanja nisu ispunjena, trebali bismo ih promijeniti.
09:18
But this is not what we find.
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No to nije ono što smo otkrili.
09:19
We asked people to come into our lab
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Zamolili smo ljude da dođu u naš laboratorij
09:23
in order to try and figure out what was going on.
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kako bismo pokušali shvatiti što se događa.
09:26
We asked them to estimate their likelihood
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Zamolili smo ih da procjene vjerojatnost
09:28
of experiencing different terrible events in their lives.
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da će im se dogoditi različiti užasni događaji.
09:31
So, for example, what is your likelihood of suffering from cancer?
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Pitali smo ih primjerice koja je vjerojatnost
da će oboljeti od raka.
da će oboljeti od raka.
09:35
And then we told them the average likelihood
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A zatim smo im rekli koja je prosječna vjerojatnost
09:37
of someone like them to suffer these misfortunes.
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za osobe poput njih da će im se dogoditi ovakve nedaće.
09:40
So cancer, for example, is about 30 percent.
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Primjerice, vjerojatnost oboljenja od raka je 30 posto.
09:44
And then we asked them again,
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Zatim smo ih ponovo pitali:
09:47
"How likely are you to suffer from cancer?"
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"Kolika je vjerojatnost da ćete oboljeti od raka?"
09:50
What we wanted to know was
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Željeli smo saznati
09:52
whether people will take the information that we gave them
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hoće li ljudi upotrijebiti informaciju koju smo im dali
09:55
to change their beliefs.
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da promjene svoja uvjerenja.
09:57
And indeed they did --
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I uistinu su to učinili --
09:59
but mostly when the information we gave them
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no uglavnom onda kada je informacija koju smo im dali
10:02
was better than what they expected.
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bila bolja od onog što su očekivali.
10:04
So for example,
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Tako, na primjer,
10:06
if someone said, "My likelihood of suffering from cancer
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ako je osoba rekla: "Vjerojatnost da ću oboljeti od raka
10:09
is about 50 percent,"
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je oko 50 posto.",
10:11
and we said, "Hey, good news.
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nakon čega smo mi rekli: "Čuj, imamo dobre vijesti,
10:14
The average likelihood is only 30 percent,"
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vjerojatnost je samo 30 posto.",
10:16
the next time around they would say,
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u idućem krugu bi rekli:
10:18
"Well maybe my likelihood is about 35 percent."
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"Mislim da je moja vjerojatnost oko 35 posto."
10:21
So they learned quickly and efficiently.
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Dakle učili su brzo i učinkovito.
10:24
But if someone started off saying,
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No ako je osoba prvotno rekla:
10:26
"My average likelihood of suffering from cancer is about 10 percent,"
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"Moja vjerojatnost da ću oboljeti od raka je oko 10 posto",
10:30
and we said, "Hey, bad news.
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nakon čega smo mi rekli: "Čuj, imamo loše vijesti,
10:32
The average likelihood is about 30 percent,"
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prosječna vjerojatnost je oko 30 posto",
10:35
the next time around they would say,
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u idućem krugu bi rekli:
10:37
"Yep. Still think it's about 11 percent."
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"Da. Još uvijek mislim da je oko 11 posto."
10:41
(Laughter)
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(Smijeh)
10:42
So it's not that they didn't learn at all -- they did --
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Tako da nije da nisu uopće naučili, jesu,
10:46
but much, much less than when we gave them
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ali su naučili puno, puno manje nego kad smo im dali
10:48
positive information about the future.
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pozitivne informacije o budućnosti.
10:50
And it's not that they didn't remember the numbers that we gave them;
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I nije da nisu zapamtili brojke koje smo im naveli.
10:53
everyone remembers that the average likelihood of cancer
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Svi su zapamtili da je prosječna vjerojatnost oboljenja od raka
10:56
is about 30 percent
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oko 30 posto
10:58
and the average likelihood of divorce is about 40 percent.
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i da je prosječna vjerojatnost za razvod oko 40 posto.
11:01
But they didn't think that those numbers were related to them.
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No nisu smatrali da se te brojke odnose na njih.
11:05
What this means is that warning signs such as these
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To znači da upozorenja kao primjerice da pušenje ubija,
11:10
may only have limited impact.
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mogu imati samo ograničeni učinak.
11:12
Yes, smoking kills, but mostly it kills the other guy.
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Jasno je, pušenje ubija, ali nekog drugog.
11:17
What I wanted to know was
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Ono što sam željela saznati je bilo
11:18
what was going on inside the human brain
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što se događa u ljudskom mozgu
11:21
that prevented us from taking these warning signs personally.
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što nas sprječava da ovakva upozorenja
shvatimo ozbiljno.
shvatimo ozbiljno.
11:25
But at the same time,
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Istovremeno,
11:27
when we hear that the housing market is hopeful,
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1978
kada čujemo da situacija na tržištu nekretnina ide na bolje
11:29
we think, "Oh, my house is definitely going to double in price."
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pomislimo: "Mojoj kući će se udvostručiti cijena."
11:33
To try and figure that out,
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Kako bismo pokušali to shvatiti,
11:35
I asked the participants in the experiment
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zamolila sam sudionike pokusa
11:38
to lie in a brain imaging scanner.
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da legnu u skener za slikanje mozga.
11:40
It looks like this.
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On izgleda ovako.
11:41
And using a method called functional MRI,
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Koristeći metodu koja se naziva
funkcionalna magnetska rezonancija
funkcionalna magnetska rezonancija
11:44
we were able to identify regions in the brain
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mogli smo identificirati područja u mozgu
11:48
that were responding to positive information.
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koja su reagirala na pozitivne informacije.
11:51
One of these regions is called the left inferior frontal gyrus.
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Jedno od tih područja se naziva lijeva donja frontalna vijuga.
11:54
So if someone said, "My likelihood of suffering from cancer is 50 percent,"
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Stoga ako je osoba rekla: "Moja vjerojatnost da ću oboljeti od raka je 50 posto",
11:58
and we said, "Hey, good news.
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na što bi mi rekli: "Čuj, dobre vijesti,
12:00
Average likelihood is 30 percent,"
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prosječna vjerojatnost je 30 posto.",
12:02
the left inferior frontal gyrus would respond fiercely.
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lijeva donja frontalna vijuga bi snažno reagirala.
12:06
And it didn't matter if you're an extreme optimist, a mild optimist
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I nije bilo važno jeste li krajnje optimistična, blago optimistična
12:10
or slightly pessimistic,
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ili lagano pesimistična osoba,
12:12
everyone's left inferior frontal gyrus
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svačija lijeva frontalna vijuga
12:15
was functioning perfectly well,
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je funkcionirala savršeno dobro,
12:17
whether you're Barack Obama or Woody Allen.
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bilo da ste Barack Obama ili Woody Allen.
12:20
On the other side of the brain,
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Na drugoj strani mozga,
12:21
the right inferior frontal gyrus was responding to bad news.
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desna donja frontalna vijuga je odgovarala na loše vijesti.
12:26
And here's the thing: it wasn't doing a very good job.
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I evo u čemu je stvar: nije baš dobro obavljala svoj zadatak.
12:30
The more optimistic you were,
256
734406
2015
Što ste bili optmističniji,
12:32
the less likely this region was
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manje je bilo vjerojatno da će ovo područje
12:34
to respond to unexpected negative information.
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reagirati na neočekivane negativne informacije.
12:37
And if your brain is failing
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Ako vaš mozak ne uspijeva
12:40
at integrating bad news about the future,
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integrirati loše vijesti o budućnosti,
12:43
you will constantly leave your rose-tinted spectacles on.
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vi ćete neprekidno gledati kroz ružičaste naočale.
12:48
So we wanted to know, could we change this?
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Stoga smo željeli saznati možemo li ovo promijeniti.
12:53
Could we alter people's optimism bias
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Možemo li izmjeniti ljudsku sklonost optimizmu
12:56
by interfering with the brain activity in these regions?
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utječući na moždanu aktivnost u ovim područjima mozga.
13:00
And there's a way for us to do that.
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I postoji način da to i učinimo.
13:03
This is my collaborator Ryota Kanai.
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Ovo je moj suradnik Ryota Kanai.
13:06
And what he's doing is he's passing a small magnetic pulse
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On propušta mali magnetski impuls
13:10
through the skull of the participant in our study
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kroz sudionikovu lubanju
13:12
into their inferior frontal gyrus.
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u njegove donje frontalne vijuge.
13:14
And by doing that,
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Čineći to,
13:16
he's interfering with the activity of this brain region
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on utječe na aktivnost ovog područja u mozgu
13:19
for about half an hour.
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na otprilike pola sata.
13:20
After that everything goes back to normal, I assure you.
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Nakon toga se, uvjeravam vas, sve vraća u normalu.
13:23
(Laughter)
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(Smijeh)
13:25
So let's see what happens.
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Da vidimo što se događa.
13:28
First of all, I'm going to show you
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Prvo ću vam pokazati
13:30
the average amount of bias that we see.
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prosječnu količinu pristranosti koju vidimo.
13:33
So if I was to test all of you now,
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Kada bih sve vas ovdje testirala,
13:36
this is the amount that you would learn
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ovo je koliko više biste naučili
13:37
more from good news relative to bad news.
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iz dobrih vijesti u odnosu na loše vijesti.
13:41
Now we interfere with the region
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Kada utječemo na područje
13:43
that we found to integrate negative information in this task,
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za koje smo utvrdili da integrira
negativne informacije u ovom zadatku,
negativne informacije u ovom zadatku,
13:48
and the optimism bias grew even larger.
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sklonost optmizmu je još više porasla.
13:51
We made people more biased in the way that they process information.
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Učinili smo ljude još pristranijima u načinu na koji su obrađivali informacije.
13:57
Then we interfered with the brain region
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Zatim smo utjecali na područje u mozgu
13:59
that we found to integrate good news in this task,
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za koje smo utvrdili da integrira dobre vijesti u ovom zadatku
14:03
and the optimism bias disappeared.
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i sklonost optimizmu je nestala.
14:07
We were quite amazed by these results
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2008
Bili smo zapanjeni ovim rezultatima
14:09
because we were able to eliminate
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jer smo uspjeli otkloniti
14:12
a deep-rooted bias in humans.
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duboko ukorijenjenu sklonost kod ljudi.
14:15
And at this point we stopped and we asked ourselves,
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U tom trenutku smo se zapitali
14:20
would we want to shatter the optimism illusion into tiny little bits?
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želimo li razbiti iluziju optimizma u malene komadiće?
14:25
If we could do that, would we want to take people's optimism bias away?
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Kada bismo to mogli učiniti, želimo li ljudima oduzeti njihovu sklonost optimizmu?
14:30
Well I've already told you about all of the benefits of the optimism bias,
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Već smo vam govorili o svim dobrobitima sklonosti optimizmu
14:34
which probably makes you want to hold onto it for dear life.
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zbog kojih je želite zadržati po svaku cijenu.
14:39
But there are, of course, pitfalls,
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2085
No, naravno, postoje zamke
14:41
and it would be really foolish of us to ignore them.
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koje bi bilo blesavo ignorirati.
14:44
Take for example this email I recieved
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Uzmite na primjer ovu e-poštu koju sam primila
14:47
from a firefighter here in California.
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od vatrogasca iz Kalifornije.
14:50
He says, "Fatality investigations for firefighters
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3304
On kaže: "Istrage smrtonosnih ozljeda u radu vatrogasaca
14:53
often include 'We didn't think the fire was going to do that,'
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4142
često uključuju objašnjenja poput 'Nismo mislili da će vatra to učiniti',
14:58
even when all of the available information
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čak i kada su postojale sve raspoložive informacije
15:00
was there to make safe decisions."
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za donošenje sigurnih odluka."
15:02
This captain is going to use our findings on the optimism bias
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Ovaj vatrogasni zapovjednik će iskoristiti rezultate našeg istraživanja o sklonosti optimizmu
15:06
to try to explain to the firefighters
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kako bi pokušao objasniti vatrogascima
15:08
why they think the way they do,
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zašto razmišljaju na način na koji razmišljaju
15:10
to make them acutely aware of this very optimistic bias in humans.
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s ciljem osvješćivanja o sklonosti optmizmu kod ljudi.
15:18
So unrealistic optimism can lead to risky behavior,
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5119
Nerealni optimizam vodi u rizično ponašanje,
15:23
to financial collapse, to faulty planning.
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3638
financijski kolaps, pogrešno planiranje.
15:26
The British government, for example,
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Britanska vlada je, primjerice,
15:28
has acknowledged that the optimism bias
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2674
prepoznala da sklonost optimizmu
15:31
can make individuals more likely
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3287
može pojedince navesti
15:34
to underestimate the costs and durations of projects.
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4026
da podcijene troškove i trajanje projekata.
15:38
So they have adjusted the 2012 Olympic budget
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4254
Stoga su budžet za Olimpijske igre 2012. godine prilagodili
15:43
for the optimism bias.
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2111
sklonosti optimizmu.
15:45
My friend who's getting married in a few weeks
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2187
Moj prijatelj koji se ženi za nekoliko tjedana
15:47
has done the same for his wedding budget.
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2434
je isto učinio za svoj budžet za vjenčanje.
15:49
And by the way, when I asked him about his own likelihood of divorce,
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3062
Usput, kad sam ga pitala koja je vjerojatnost
da će se razvesti
da će se razvesti
15:52
he said he was quite sure it was zero percent.
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3560
rekao je kako je prilično siguran da je to, nula posto.
15:56
So what we would really like to do,
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2417
Ono što bismo stvarno željeli učiniti
15:58
is we would like to protect ourselves from the dangers of optimism,
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4161
je zaštititi same sebe od opasnosti optimizma,
16:03
but at the same time remain hopeful,
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3228
no u isto vrijeme ostati puni nade,
16:06
benefiting from the many fruits of optimism.
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2844
uživajući pogodnosti optimizma.
16:09
And I believe there's a way for us to do that.
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2804
Ja vjerujem da postoji način da to učinimo.
16:11
The key here really is knowledge.
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2060
Ključ je u znanju.
16:14
We're not born with an innate understanding of our biases.
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3311
Ne rađamo se s urođenim razumijevanjem naših sklonosti.
16:17
These have to be identified by scientific investigation.
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One se moraju utvrditi znanstvenim istraživanjem.
16:21
But the good news is that becoming aware of the optimism bias
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4184
No dobra vijest je osvješćivanje postojanja sklonosti optimizmu
16:25
does not shatter the illusion.
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ne uništava iluziju.
16:27
It's like visual illusions,
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1548
Isto je kao i s vizualnim iluzijama
16:28
in which understanding them does not make them go away.
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u kojima njihovo razumijevanje ne uzrokuje njihovo nestajanje.
16:32
And this is good because it means
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2237
To je dobro jer znači
16:34
we should be able to strike a balance,
333
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da bismo trebali moći naći ravnotežu,
16:36
to come up with plans and rules
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smisliti planove i pravila
16:39
to protect ourselves from unrealistic optimism,
335
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2783
kojima ćemo se zaštititi od nerealnog optimizma,
16:42
but at the same time remain hopeful.
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a u isto vrijeme zadržati nadu.
16:45
I think this cartoon portrays it nicely.
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Mislim da ovaj crtež to dobro oslikava.
16:48
Because if you're one of these pessimistic penguins up there
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Ako ste jedan od ovih pesimističnih pingvina,
16:52
who just does not believe they can fly,
339
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2119
koji jednostavno ne vjeruju da mogu poletjeti,
16:54
you certainly never will.
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sigurno ni nećete poletjeti.
16:56
Because to make any kind of progress,
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Da bismo ostvarili bilo kakav napredak
16:58
we need to be able to imagine a different reality,
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moramo moći zamisliti drugačiju stvarnost,
17:00
and then we need to believe that that reality is possible.
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a zatim moramo vjerovati da je ta stvarnost uistinu moguća.
17:04
But if you are an extreme optimistic penguin
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No ako ste pretjerano optmistični pingvin
17:08
who just jumps down blindly hoping for the best,
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koji samo skoči bez razmišljanja nadajući se najboljem,
17:10
you might find yourself in a bit of a mess when you hit the ground.
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mogli bi se naći u problemu kada udarite o tlo.
17:15
But if you're an optimistic penguin
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No ako ste optmističan pingvin
17:17
who believes they can fly,
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koji vjeruje da može letjeti,
17:19
but then adjusts a parachute to your back
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no koji priveže padobran za leđa
17:22
just in case things don't work out exactly as you had planned,
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za slučaj da stvari ne ispadnu onako kako ste planirali,
17:25
you will soar like an eagle,
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letjet ćete poput orla,
17:26
even if you're just a penguin.
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čak i ako ste samo pingvin.
17:29
Thank you.
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Hvala vam.
17:31
(Applause)
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(Pljesak)
ABOUT THE SPEAKER
Tali Sharot - Cognitive neuroscientistTali Sharot studies why our brains are biased toward optimism.
Why you should listen
Optimism bias is the belief that the future will be better, much better, than the past or present. And most of us display this bias. Neuroscientist Tali Sharot wants to know why: What is it about our brains that makes us overestimate the positive? She explores the question in her book The Optimism Bias: A Tour of the Irrationally Positive Brain.
In the book (and a 2011 TIME magazine cover story), she reviewed findings from both social science and neuroscience that point to an interesting conclusion: "our brains aren't just stamped by the past. They are constantly being shaped by the future." In her own work, she's interested in how our natural optimism actually shapes what we remember, and her interesting range of papers encompasses behavioral research (how likely we are to misremember major events) as well as medical findings -- like searching for the places in the brain where optimism lives. Sharot is a faculty member of the Department of Cognitive, Perceptual and Brain Sciences at University College London.
Tali Sharot | Speaker | TED.com