TED2012
Tali Sharot: The optimism bias
Tali Sharot: Den optimistiske tilbøjelighed
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Bliver vi født til at være optimistiske, frem for realistiske? Tali Sharot deler ny forskning der foreslår, at vores hjerne er bygget til at kigge på den lyse side -- og hvordan det kan være både farligt og fordelagtigt.
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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Jeg vil tale til jer om optimisme --
00:19
or more precisely, the optimism bias.
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eller mere præcist, den optimistiske tilbøjelighed.
00:21
It's a cognitive illusion
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Det er en kognitiv illusion
00:23
that we've been studying in my lab for the past few years,
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som vi har undersøgt i mit laboratorium i løbet af de sidste par år,
00:26
and 80 percent of us have it.
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og 80 procent af os har den.
00:28
It's our tendency to overestimate
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Det er vores tendens til at overvurdere
00:30
our likelihood of experiencing good events in our lives
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vores sandsynlighed for at opleve gode begivenheder i vores liv
00:33
and underestimate our likelihood of experiencing bad events.
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og undervurdere sandsynligheden for at opleve dårlige begivenheder.
00:37
So we underestimate our likelihood of suffering from cancer,
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Så vi undervurderer vores sandsynlighed for at lide af kræft,
00:40
being in a car accident.
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være i et biluheld.
00:42
We overestimate our longevity, our career prospects.
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Vi overvurderer vores levealder, vores karriere udsigter.
00:45
In short, we're more optimistic than realistic,
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Kort sagt, er vi mere optimistiske end realistiske,
00:48
but we are oblivious to the fact.
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men vi er ikke bevidste om det faktum.
00:51
Take marriage for example.
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Kig for eksempel på ægteskabet.
00:53
In the Western world, divorce rates are about 40 percent.
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I den vestlige verden, er sandsynligheden for skilsmisse på cirka 40 procent.
00:56
That means that out of five married couples,
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Det betyder at ud af fem gifte par,
01:00
two will end up splitting their assets.
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vil der i sidste ende være to par der ender med at dele deres aktiver.
01:03
But when you ask newlyweds about their own likelihood of divorce,
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Men når man spørger nygifte om deres egen sandsynlighed for skilsmisse,
01:06
they estimate it at zero percent.
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vurderer de den til at være nul procent.
01:10
And even divorce lawyers, who should really know better,
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Og selv skilsmisse advokater, der virkelig burde vide bedre,
01:13
hugely underestimate their own likelihood of divorce.
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undervurderer i høj grad deres egen sandsynlighed for skilsmisse.
01:17
So it turns out that optimists are not less likely to divorce,
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Så det viser sig, at optimister ikke har lavere sandsynlighed for skilsmisse,
01:20
but they are more likely to remarry.
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men de har større sandsynlighed for at gifte sig igen.
01:23
In the words of Samuel Johnson,
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Som Samuel Johnson sagde,
01:25
"Remarriage is the triumph of hope over experience."
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"At gifte sig igen er håbets triumf over erfaring."
01:29
(Laughter)
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(Latter)
01:31
So if we're married, we're more likely to have kids.
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Så hvis vi er gift, er der større sandsynlighed for at få børn.
01:36
And we all think our kids will be especially talented.
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Og vi mener alle at vores børn vil være specielt talentfulde.
01:39
This, by the way, is my two-year-old nephew, Guy.
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Dette, forresten, er min to-årige nevø, Guy.
01:42
And I just want to make it absolutely clear
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Og jeg vil bare gøre det helt klart ,
01:44
that he's a really bad example of the optimism bias,
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at han er et virkelig dårligt eksempel på optimistiske tilbøjelighed,
01:47
because he is in fact uniquely talented.
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fordi han er faktisk enestående talentfuld.
01:50
(Laughter)
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(Latter)
01:51
And I'm not alone.
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Og det er ikke kun mig.
01:53
Out of four British people, three said
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Ud af fire britiske folk, sagde tre,
01:55
that they were optimistic about the future of their own families.
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at de var optimistiske omkring deres egen families fremtid.
01:59
That's 75 percent.
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Det er 75 procent.
02:01
But only 30 percent said
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Men kun 30 procent sagde,
02:03
that they thought families in general
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at de mente, at familier generelt
02:05
are doing better than a few generations ago.
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klarer sig bedre end for et par generationer siden.
02:08
And this is a really important point,
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Og det er en virkelig vigtigt pointe,
02:10
because we're optimistic about ourselves,
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fordi vi er optimistiske om os selv,
02:11
we're optimistic about our kids,
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vi er optimistiske om vores børn,
02:13
we're optimistic about our families,
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vi er optimistiske om vores familier,
02:15
but we're not so optimistic about the guy sitting next to us,
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men vi er ikke så optimistiske om fyren der sidder ved siden af os,
02:18
and we're somewhat pessimistic
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og vi er noget pessimistiske
02:20
about the fate of our fellow citizens and the fate of our country.
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om vores medborgere skæbne og vores lands skæbne.
02:24
But private optimism about our own personal future
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Men privat optimisme om vores egen personlige fremtid
02:28
remains persistent.
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bliver ved med at være vedholdende.
02:30
And it doesn't mean that we think things will magically turn out okay,
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Og det betyder ikke at vi mener at tingene på magisk vis bliver ok,
02:34
but rather that we have the unique ability to make it so.
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men at vi har den specielle evne til at få det til det.
02:39
Now I'm a scientist, I do experiments.
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Nu er jeg forsker, jeg laver eksperimenter.
02:41
So to show you what I mean,
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Så for at vise jer hvad jeg mener,
02:43
I'm going to do an experiment here with you.
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vil jeg lave et eksperiment med jer.
02:46
So I'm going to give you a list of abilities and characteristics,
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Så jeg vil give jer en liste af evner og karakteristika,
02:50
and I want you to think for each of these abilities
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og jeg vil gerne have at I for hver af disse evner
02:53
where you stand relative to the rest of the population.
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tænker over hvor I er, i forhold til resten af befolkningen.
02:57
The first one is getting along well with others.
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Den første er at komme godt ud af det med andre.
03:01
Who here believes they're at the bottom 25 percent?
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Hvem her tror på at de er blandt de nederste 25 procent?
03:07
Okay, that's about 10 people out of 1,500.
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Okay, det er cirka 10 mennesker ud af 1.500.
03:11
Who believes they're at the top 25 percent?
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Hvem mener de er i de øverste 25 procent?
03:15
That's most of us here.
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Det er de fleste af os.
03:18
Okay, now do the same for your driving ability.
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Okay, nu gælder det samme for jeres køreegenskaber.
03:22
How interesting are you?
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Hvor interessant er du?
03:25
How attractive are you?
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Hvor tiltrækkende er du?
03:28
How honest are you?
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Hvor ærlig er du?
03:31
And finally, how modest are you?
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Og til slut, hvor beskeden er du?
03:36
So most of us put ourselves above average
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Så de fleste af os, sætter os selv over gennemsnittet
03:39
on most of these abilities.
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i de fleste af disse evner.
03:41
Now this is statistically impossible.
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Det er statistisk set umuligt.
03:43
We can't all be better than everyone else.
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Vi kan ikke alle være bedre end alle andre.
03:46
(Laughter)
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(Latter)
03:48
But if we believe we're better than the other guy,
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Men hvis vi mener vi er bedre end den anden fyr,
03:50
well that means that we're more likely to get that promotion, to remain married,
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så betyder det at der er en større sandsynlighed for at vi får en forfremmelse, at forblive gift,
03:54
because we're more social, more interesting.
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fordi vi er mere sociale, mere interessante.
03:57
And it's a global phenomenon.
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Og det er et globalt fænomen.
03:59
The optimism bias has been observed
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Den optimistiske tilbøjelighed er blevet observeret
04:02
in many different countries --
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i mange forskellige lande --
04:03
in Western cultures, in non-Western cultures,
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i vestlige kulturer, i ikke-vestlige kulturer,
04:06
in females and males,
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hos kvinder og mænd,
04:08
in kids, in the elderly.
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hos børn, hos de ældre.
04:10
It's quite widespread.
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Det er ret udbredt.
04:11
But the question is, is it good for us?
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Men spørgsmålet er, er det godt for os?
04:15
So some people say no.
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Så nogle mennesker siger nej.
04:17
Some people say the secret to happiness
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Nogle mennesker siger at hemmeligheden bag lykke
04:20
is low expectations.
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er lave forventninger.
04:23
I think the logic goes something like this:
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Jeg tror logikken er noget i denne retning:
04:25
If we don't expect greatness,
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Hvis vi ikke forventer storslåethed,
04:27
if we don't expect to find love and be healthy and successful,
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hvis vi ikke forventer at finde kærlighed og være sunde og succesrige,
04:31
well we're not going to be disappointed when these things don't happen.
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jamen så bliver vi ikke skuffede, når disse ting ikke sker.
04:34
And if we're not disappointed when good things don't happen,
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Og hvis vi ikke er skuffede når der sker gode ting,
04:38
and we're pleasantly surprised when they do,
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og vi bliver glædeligt overraskede når de sker,
04:40
we will be happy.
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bliver vi lykkelige.
04:42
So it's a very good theory,
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Så det er en meget god teori,
04:43
but it turns out to be wrong for three reasons.
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men det viser sig at være forkert, af tre årsager.
04:46
Number one: Whatever happens, whether you succeed or you fail,
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Nummer et: Hvad der end sker, uanset om man lykkedes eller fejler,
04:51
people with high expectations always feel better.
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har mennesker med høje forventninger det altid bedre.
04:55
Because how we feel when we get dumped or win employee of the month
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Fordi det vi føler når vi bliver dumpet eller bliver månedens medarbejder,
04:59
depends on how we interpret that event.
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kommer an på hvordan vi fortolker den begivenhed.
05:02
The psychologists Margaret Marshall and John Brown
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Psykologerne Margaret Marshall og John Brown
05:06
studied students with high and low expectations.
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undersøgte studerende med høje og lave forventninger.
05:09
And they found that when people with high expectations succeed,
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Og de fandt ud af, at når mennesker med høje forventninger har succes,
05:13
they attribute that success to their own traits.
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tilskriver de den succes deres egne evner.
05:16
"I'm a genius, therefore I got an A,
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"Jeg er et geni, derfor fik jeg et A,
05:18
therefore I'll get an A again and again in the future."
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derfor får jeg et A igen og igen i fremtiden."
05:21
When they failed, it wasn't because they were dumb,
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Da de dumpede, var det ikke fordi de var dumme,
05:24
but because the exam just happened to be unfair.
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men fordi eksamenen bare var unfair.
05:27
Next time they will do better.
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Næste gang vil de klare sig bedre.
05:29
People with low expectations do the opposite.
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Mennesker med lave forventninger gør det modsatte.
05:32
So when they failed it was because they were dumb,
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Så når de dumper var det fordi de var dumme,
05:35
and when they succeeded
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og da de bestod
05:37
it was because the exam just happened to be really easy.
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var det fordi den eksamen bare var rigtig nem.
05:40
Next time reality would catch up with them.
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Næste gang vil virkeligheden indhente dem.
05:42
So they felt worse.
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Så de havde det dårligere.
05:44
Number two: Regardless of the outcome,
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Nummer to: Uanset udfaldet,
05:48
the pure act of anticipation makes us happy.
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selve forventningen gør os lykkelige.
05:52
The behavioral economist George Lowenstein
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Adfærds økonomen George Lowenstein,
05:55
asked students in his university
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bad de studerende ved hans universitet
05:57
to imagine getting a passionate kiss from a celebrity, any celebrity.
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om at forestille sig at få et følelsesrigt kys fra en kendt, en hvilken som helst kendt.
06:01
Then he said, "How much are you willing to pay
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Så sagde han, "Hvor meget er I villige til at betale
06:04
to get a kiss from a celebrity
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for at få et kys fra en kendis
06:06
if the kiss was delivered immediately,
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hvis kysset blev afleveret med det samme,
06:08
in three hours, in 24 hours, in three days,
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om tre timer, om 24 timer, om tre dage,
06:13
in one year, in 10 years?
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om 1 år, om 10 år?
06:15
He found that the students were willing to pay the most
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Han fandt ud af, at de studerende var villige til at betale mest
06:19
not to get a kiss immediately,
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for ikke at få et kys med det samme,
06:21
but to get a kiss in three days.
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men for at få et kys om tre dage.
06:24
They were willing to pay extra in order to wait.
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De var villige til at betale ekstra, for at få lov til at vente.
06:28
Now they weren't willing to wait a year or 10 years;
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Nu var de ikke villige til at vente et år eller 10 år;
06:31
no one wants an aging celebrity.
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ingen vil have en aldrende kendis.
06:32
But three days seemed to be the optimum amount.
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Men tre dage virkede som den optimale mængde.
06:37
So why is that?
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Så hvorfor det?
06:39
Well if you get the kiss now, it's over and done with.
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Jamen, hvis man får kysset nu, er det slut.
06:43
But if you get the kiss in three days,
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Men hvis man får kysset om tre dage,
06:45
well that's three days of jittery anticipation, the thrill of the wait.
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jamen det er tre dage med forventning, forventningens glæde.
06:49
The students wanted that time
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De studerende ville have den tid
06:51
to imagine where is it going to happen,
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til at forestille sig hvad der sker,
06:53
how is it going to happen.
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hvordan sker det.
06:55
Anticipation made them happy.
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Forventningen gjorde dem lykkelige.
06:57
This is, by the way, why people prefer Friday to Sunday.
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Dette er, i øvrigt, hvorfor folk foretrækker fredag frem for søndag.
07:01
It's a really curious fact,
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Det er et virkelig besynderligt faktum,
07:03
because Friday is a day of work and Sunday is a day of pleasure,
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fordi er en arbejdsdag og søndag er en glædens dag,
07:06
so you'd assume that people will prefer Sunday,
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så man skulle tro at folk ville foretrække søndag,
07:09
but they don't.
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men det gør de ikke.
07:11
It's not because they really, really like being in the office
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Det er ikke fordi de virkelig, virkelig godt kan lide at være på kontoret,
07:14
and they can't stand strolling in the park
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og de ikke kan holde det ud at gå en tur i parken
07:16
or having a lazy brunch.
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eller have en sen brunch.
07:17
We know that, because when you ask people
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Det ved vi, fordi når man spørger folk
07:20
about their ultimate favorite day of the week,
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om deres ultimative favoritdag i ugen,
07:22
surprise, surprise, Saturday comes in at first,
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surprise, surprise, lørdag er på førstepladsen,
07:25
then Friday, then Sunday.
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så fredag, så søndag.
07:28
People prefer Friday
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Folk foretrækker fredag,
07:30
because Friday brings with it the anticipation of the weekend ahead,
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fordi fredagen bringer forventningens glæde om den foreliggende weekend,
07:34
all the plans that you have.
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alle de planer man har.
07:36
On Sunday, the only thing you can look forward to
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Om søndagen, den eneste ting man kan se frem til
07:38
is the work week.
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er arbejdsugen.
07:41
So optimists are people who expect more kisses in their future,
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Så optimistiske mennesker, er mennesker der forventer flere kys i deres fremtid,
07:46
more strolls in the park.
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flere gåture i parken.
07:48
And that anticipation enhances their wellbeing.
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Og den forventning forstærker deres velbefindende.
07:51
In fact, without the optimism bias,
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Faktisk, uden den optimistiske tilbøjelighed,
07:54
we would all be slightly depressed.
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ville vi alle være en smule deprimerede.
07:57
People with mild depression,
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Mennesker med en mild depression,
07:59
they don't have a bias when they look into the future.
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de har ikke en tilbøjelighed når de kigger ind i fremtiden.
08:02
They're actually more realistic than healthy individuals.
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De er faktisk mere realistiske end sunde individer.
08:07
But individuals with severe depression,
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Men individer med svære depressioner,
08:09
they have a pessimistic bias.
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de har en pessimistisk tilbøjelighed.
08:11
So they tend to expect the future
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Så de har en tendens til at forvente at fremtiden
08:13
to be worse than it ends up being.
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er værre end den ender med at være.
08:15
So optimism changes subjective reality.
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Så optimisme ændrer den subjektive virkelighed.
08:19
The way we expect the world to be changes the way we see it.
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Måden hvorpå vi forventer at verden ændrer sig, ændrer måden hvorpå vi ser den.
08:22
But it also changes objective reality.
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Men det ændrer også den objektive virkelighed.
08:26
It acts as a self-fulfilling prophecy.
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Det ender som en selvopfyldende profeti.
08:28
And that is the third reason
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Og det er den tredje grund til,
08:31
why lowering your expectations will not make you happy.
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hvorfor det at sænke ens forventninger ikke vil gøre en lykkelig.
08:34
Controlled experiments have shown
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Kontrollerede eksperimenter har vist
08:36
that optimism is not only related to success,
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at optimisme ikke kun relaterer sig til succes,
08:38
it leads to success.
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det fører til succes.
08:40
Optimism leads to success in academia and sports and politics.
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Optimisme fører til succes i den akademiske verden, sportsverden og den politiske verden.
08:45
And maybe the most surprising benefit of optimism is health.
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Og måske er den mest overraskende fordel ved optimisme helbredet.
08:50
If we expect the future to be bright,
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Hvis vi forventer at fremtiden er lys,
08:53
stress and anxiety are reduced.
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bliver stress og angst reduceret.
08:56
So all in all, optimism has lots of benefits.
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Så, alt i alt, optimisme har mange fordele.
09:00
But the question that was really confusing to me was,
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Men det spørgsmål der virkelig forvirrede mig var,
09:03
how do we maintain optimism in the face of reality?
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hvordan fastholder vi optimismen på trods af virkeligheden?
09:08
As an neuroscientist, this was especially confusing,
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Som forsker i neurovidenskab, var det specielt forvirrende,
09:11
because according to all the theories out there,
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fordi ifølge alle teorierne derude,
09:13
when your expectations are not met, you should alter them.
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når ens forventninger ikke bliver indfriet, burde man ændre dem.
09:18
But this is not what we find.
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Men det er ikke det vi fandt ud af.
09:19
We asked people to come into our lab
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Vi bad mennesker om at komme ind i vores laboratorium,
09:23
in order to try and figure out what was going on.
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for at prøve at finde ud af hvad der skete.
09:26
We asked them to estimate their likelihood
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Vi bad dem om at evaluere deres sandsynlighed
09:28
of experiencing different terrible events in their lives.
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for at opleve forskellige forfærdelige begivenheder i deres liv.
09:31
So, for example, what is your likelihood of suffering from cancer?
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Så, for eksempel, hvad er din sandsynlighed for at få kræft?
09:35
And then we told them the average likelihood
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Og så fortalte vi dem den gennemsnitlige sandsynlighed
09:37
of someone like them to suffer these misfortunes.
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for at en person lider disse uheldige skæbner.
09:40
So cancer, for example, is about 30 percent.
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Så kræft, for eksempel, er cirka 30 procent.
09:44
And then we asked them again,
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Og så spurgte vi dem igen,
09:47
"How likely are you to suffer from cancer?"
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"Hvor stor er sandsynligheden for at du kommer til at få kræft?"
09:50
What we wanted to know was
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Det vi ville finde ud af var,
09:52
whether people will take the information that we gave them
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om mennesker tager den information vi gav dem
09:55
to change their beliefs.
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og ændrede deres holdninger.
09:57
And indeed they did --
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Og det gjorde de --
09:59
but mostly when the information we gave them
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men for det meste når den information vi gav dem
10:02
was better than what they expected.
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var bedre end det de forventede.
10:04
So for example,
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Så for eksempel,
10:06
if someone said, "My likelihood of suffering from cancer
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hvis nogen sagde, "Min sandsynlighed for at få kræft
10:09
is about 50 percent,"
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er cirka 50 procent."
10:11
and we said, "Hey, good news.
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Og vi sagde, "Hey, godt nyt.
10:14
The average likelihood is only 30 percent,"
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Den gennemsnitlige sandsynlighed er 30 procent,"
10:16
the next time around they would say,
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den næste gang ville de sige,
10:18
"Well maybe my likelihood is about 35 percent."
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"Jamen måske er min sandsynlighed cirka 35 procent."
10:21
So they learned quickly and efficiently.
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Så de lærte hurtigt og effektivt.
10:24
But if someone started off saying,
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Men hvis nogen begyndte med at sige,
10:26
"My average likelihood of suffering from cancer is about 10 percent,"
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"Min sandsynlighed for at få kræft er cirka 10 procent,"
10:30
and we said, "Hey, bad news.
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og vi sagde, "Hey, dårligt nyt.
10:32
The average likelihood is about 30 percent,"
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Den gennemsnitlige sandsynlighed er 30 procent,"
10:35
the next time around they would say,
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den næste gang ville de sige,
10:37
"Yep. Still think it's about 11 percent."
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"Yep. Tror stadig den er cirka 11 procent."
10:41
(Laughter)
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(Latter)
10:42
So it's not that they didn't learn at all -- they did --
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Så det er ikke fordi de ikke lærte noget -- det gjorde de --
10:46
but much, much less than when we gave them
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men meget, meget mindre end når vi gav dem
10:48
positive information about the future.
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positiv information om fremtiden.
10:50
And it's not that they didn't remember the numbers that we gave them;
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Og det er ikke fordi de ikke huskede de tal vi gav dem;
10:53
everyone remembers that the average likelihood of cancer
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alle kan huske at den gennemsnitlige sandsynlighed for at få kræft
10:56
is about 30 percent
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1500
er cirka 30 procent,
10:58
and the average likelihood of divorce is about 40 percent.
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2779
og den gennemsnitlige sandsynlighed for skilsmisse er 40 procent.
11:01
But they didn't think that those numbers were related to them.
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Men de mente ikke, at de tal havde noget med dem at gøre.
11:05
What this means is that warning signs such as these
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Det det betyder er, at advarselsskilte som disse
11:10
may only have limited impact.
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har muligvis kun en begrænset indvirkning.
11:12
Yes, smoking kills, but mostly it kills the other guy.
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Ja, rygning dræber, men det dræber for det mest den anden fyr.
11:17
What I wanted to know was
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Det jeg ville vide var,
11:18
what was going on inside the human brain
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hvad sker der i den menneskelige hjerne,
11:21
that prevented us from taking these warning signs personally.
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der forhindrer os i at tage disse advarselsskilte personligt.
11:25
But at the same time,
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Men samtidig,
11:27
when we hear that the housing market is hopeful,
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671483
1978
når vi hører at boligmarkedet er håbefuldt,
11:29
we think, "Oh, my house is definitely going to double in price."
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tænker vi, "Ah, mit hus bliver helt sikkert dobbelt så meget værd."
11:33
To try and figure that out,
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For at prøve og finde ud af det,
11:35
I asked the participants in the experiment
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bad jeg de deltagende i eksperimentet
11:38
to lie in a brain imaging scanner.
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om at lyve i en billeddannelses scanner.
11:40
It looks like this.
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Det ser sådan ud.
11:41
And using a method called functional MRI,
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Og ved at bruge en metode der hedder funktionel MRI,
11:44
we were able to identify regions in the brain
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var vi i stand til at identificere de områder i hjernen
11:48
that were responding to positive information.
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der reagerede på den positive information.
11:51
One of these regions is called the left inferior frontal gyrus.
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Et af disse områder hedder den venstre inferiøre frontale gyrus.
11:54
So if someone said, "My likelihood of suffering from cancer is 50 percent,"
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Så hvis nogen sagde, "Min sandsynlighed for at få kræft er cirka 50 procent,"
11:58
and we said, "Hey, good news.
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1856
og vi sagde, "Hey, godt nyt.
12:00
Average likelihood is 30 percent,"
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Den gennemsnitlige sandsynlighed er 30 procent,"
12:02
the left inferior frontal gyrus would respond fiercely.
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ville den venstre inferiøre frontale gyrus svare voldsomt.
12:06
And it didn't matter if you're an extreme optimist, a mild optimist
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Og det betød ikke noget om man var en ekstrem optimist, mildt optimistisk
12:10
or slightly pessimistic,
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eller lidt pessimistisk,
12:12
everyone's left inferior frontal gyrus
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2585
alles venstre inferiøre frontale gyrus
12:15
was functioning perfectly well,
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funktionerede perfekt,
12:17
whether you're Barack Obama or Woody Allen.
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uanset om man er Barack Obama eller Woody Allen.
12:20
On the other side of the brain,
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På den anden side af hjernen,
12:21
the right inferior frontal gyrus was responding to bad news.
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svarede den højre inferiøre frontale gyrus på dårligt nyt.
12:26
And here's the thing: it wasn't doing a very good job.
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Og her er hagen; den gjorde ikke et særlig godt stykke arbejde.
12:30
The more optimistic you were,
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Jo mere optimistisk man var,
12:32
the less likely this region was
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jo mindre sandsynligt var det at dette område
12:34
to respond to unexpected negative information.
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interagerede med den uventede, negative information.
12:37
And if your brain is failing
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Og hvis ens hjerne ikke formår
12:40
at integrating bad news about the future,
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at integrere dårligt nyt om fremtiden,
12:43
you will constantly leave your rose-tinted spectacles on.
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vil man konstant have ens lyserøde briller på.
12:48
So we wanted to know, could we change this?
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Så det vi ville vide var, kan vi ændre dette?
12:53
Could we alter people's optimism bias
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3443
Kunne vi ændre folks optimistiske tilbøjelighed
12:56
by interfering with the brain activity in these regions?
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ved at ændre hjerneaktiviteten i disse områder?
13:00
And there's a way for us to do that.
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2595
Og der er en måde hvorpå vi kan gøre det.
13:03
This is my collaborator Ryota Kanai.
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Dette er min samarbejdspartner Ryota Kanai.
13:06
And what he's doing is he's passing a small magnetic pulse
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Og det han gør er, at han leder en lille magnetisk puls
13:10
through the skull of the participant in our study
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2119
gennem kraniet på deltageren af vores studie
13:12
into their inferior frontal gyrus.
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2245
ind i deres inferiøre frontale gyrus.
13:14
And by doing that,
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Og ved at gøre det,
13:16
he's interfering with the activity of this brain region
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forstyrrer han aktiviteten i dette område af hjernen
13:19
for about half an hour.
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i cirka en halv time.
13:20
After that everything goes back to normal, I assure you.
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Derefter vender alt tilbage til normalen, kan jeg forsikre jer om.
13:23
(Laughter)
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1993
(Latter)
13:25
So let's see what happens.
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Så lad os se hvad der sker.
13:28
First of all, I'm going to show you
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For det første, vil jeg vise jer
13:30
the average amount of bias that we see.
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den gennemsnitlige mængde tilbøjelighed vi ser.
13:33
So if I was to test all of you now,
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Så hvis jeg ville teste jer alle sammen nu,
13:36
this is the amount that you would learn
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ville dette være mængden I ville lære
13:37
more from good news relative to bad news.
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mere fra godt nyt i forhold til dårligt nyt.
13:41
Now we interfere with the region
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Nu vil vi forstyrre dette område
13:43
that we found to integrate negative information in this task,
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som vi fandt ud af reagerede på den negative information i denne opgave,
13:48
and the optimism bias grew even larger.
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og den optimistiske tilbøjelighed voksede sig større.
13:51
We made people more biased in the way that they process information.
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Vi fik folk til at have en større tilbøjelighed i måden hvorpå de bearbejdede information.
13:57
Then we interfered with the brain region
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Så forstyrrede vi området i hjernen
13:59
that we found to integrate good news in this task,
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som vi fandt ud af reagerede på godt nyt i denne opgave,
14:03
and the optimism bias disappeared.
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og så forsvandt den optimistiske tilbøjelighed.
14:07
We were quite amazed by these results
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2008
Vi blev ret forbavsede over disse resultater
14:09
because we were able to eliminate
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fordi vi var i stand til at eliminere
14:12
a deep-rooted bias in humans.
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en dybt fæstet tilbøjelighed i mennesker.
14:15
And at this point we stopped and we asked ourselves,
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4773
Og på dette tidspunkt stoppede vi og spurgte os selv,
14:20
would we want to shatter the optimism illusion into tiny little bits?
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5102
ville vi knuse den lille optimistiske illusion i små stykker?
14:25
If we could do that, would we want to take people's optimism bias away?
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5044
Hvis vi kunne gøre det, ville vi så have lyst til at fjerne menneskers optimistiske tilbøjelighed?
14:30
Well I've already told you about all of the benefits of the optimism bias,
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Jamen jeg har allerede fortalt jer om alle fordelene ved den optimistiske tilbøjelighed,
14:34
which probably makes you want to hold onto it for dear life.
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4321
hvilket sikkert giver jer lyst til at holde fast i den som om det gjaldt livet.
14:39
But there are, of course, pitfalls,
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2085
Men der er, selvfølgelig, faldgruber,
14:41
and it would be really foolish of us to ignore them.
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og det ville være virkelig dumt af os at ignorere dem.
14:44
Take for example this email I recieved
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Tag for eksempel denne email jeg modtog
14:47
from a firefighter here in California.
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fra en brandmand her i Californien.
14:50
He says, "Fatality investigations for firefighters
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3304
Han siger, "Dødsulykke undersøgelser for brandmænd
14:53
often include 'We didn't think the fire was going to do that,'
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4142
inkluderer ofte "Vi troede ikke at ildebranden ville gøre det,"
14:58
even when all of the available information
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2302
selv når al den tilgængelige information
15:00
was there to make safe decisions."
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2255
var til stede, til at tage en sikker beslutning."
15:02
This captain is going to use our findings on the optimism bias
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3874
Denne kaptajn vil bruge vores opdagelser om den optimistiske tilbøjelighed
15:06
to try to explain to the firefighters
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2192
til at prøve at forklare brandmænd
15:08
why they think the way they do,
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2209
hvorfor de tænker som de gør,
15:10
to make them acutely aware of this very optimistic bias in humans.
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7126
for at få dem til at være opmærksomme på denne optimistiske tilbøjelighed i mennesker.
15:18
So unrealistic optimism can lead to risky behavior,
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5119
Så urealistisk optimisme kan lede til meget risikofyldt adfærd,
15:23
to financial collapse, to faulty planning.
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3638
til finansiel kollaps, til dårlig planlægning.
15:26
The British government, for example,
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Den britiske regering, for eksempel,
15:28
has acknowledged that the optimism bias
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2674
har vedkendt at den optimistiske tilbøjelighed
15:31
can make individuals more likely
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3287
kan gøre individer mere modtagelige
15:34
to underestimate the costs and durations of projects.
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4026
til at undervurdere omkostningerne og varigheden af projekter.
15:38
So they have adjusted the 2012 Olympic budget
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4254
Så de har justeret det Olympiske budget for 2012
15:43
for the optimism bias.
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2111
på grund af den optimistiske tilbøjelighed.
15:45
My friend who's getting married in a few weeks
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2187
Min ven der bliver gift om et par uger
15:47
has done the same for his wedding budget.
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2434
har gjort det samme med hans bryllups budget.
15:49
And by the way, when I asked him about his own likelihood of divorce,
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3062
Og for øvrigt, da jeg spurgte ham om hans egen sandsynlighed for skilsmisse,
15:52
he said he was quite sure it was zero percent.
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3560
sagde han, at han var ret sikker på at den var på nul procent.
15:56
So what we would really like to do,
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2417
Så det vi meget gerne vil gøre,
15:58
is we would like to protect ourselves from the dangers of optimism,
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4161
er at vi gerne vil beskytte os selv fra farerne ved optimisme,
16:03
but at the same time remain hopeful,
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3228
men samtidig forblive håbefulde,
16:06
benefiting from the many fruits of optimism.
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2844
og drage fordel af de mange goder der er ved optimisme.
16:09
And I believe there's a way for us to do that.
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2804
Og jeg mener at der er en måde vi kan gøre det på.
16:11
The key here really is knowledge.
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Nøglen her, er faktisk viden.
16:14
We're not born with an innate understanding of our biases.
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3311
Vi er ikke født med en instinktiv forståelse af vores tilbøjeligheder.
16:17
These have to be identified by scientific investigation.
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De skal identificeres af en videnskabelig undersøgelse.
16:21
But the good news is that becoming aware of the optimism bias
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4184
Men den gode nyhed er, at blive klar over den optimistiske tilbøjelighed
16:25
does not shatter the illusion.
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1775
ikke fjerner illusionen.
16:27
It's like visual illusions,
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1548
Det er ligesom visuelle illusioner,
16:28
in which understanding them does not make them go away.
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hvor det at forstå dem ikke for dem til at forsvinde.
16:32
And this is good because it means
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2237
Og det er godt nyt, fordi det betyder
16:34
we should be able to strike a balance,
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2473
at vi burde være i stand til at finde en balance,
16:36
to come up with plans and rules
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2427
til at finde på planer og regler
16:39
to protect ourselves from unrealistic optimism,
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2783
for at beskytte os selv fra urealistisk optimisme,
16:42
but at the same time remain hopeful.
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3152
men på samme tid være håbefulde.
16:45
I think this cartoon portrays it nicely.
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Jeg tror denne vittighedstegning fanger det godt.
16:48
Because if you're one of these pessimistic penguins up there
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3526
Fordi hvis man er en af disse pessimistiske pingviner deroppe
16:52
who just does not believe they can fly,
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der bare ikke tror på at de kan flyve,
16:54
you certainly never will.
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så kommer man aldrig til det.
16:56
Because to make any kind of progress,
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1831
For for at have noget fremskridt,
16:58
we need to be able to imagine a different reality,
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2350
er vi nød til at være i stand til at forestille os en anden virkelighed,
17:00
and then we need to believe that that reality is possible.
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3731
og vi skal være i stand til at tro på at den virkelighed er mulig.
17:04
But if you are an extreme optimistic penguin
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3524
Men hvis man er en ekstremt optimistisk pingvin
17:08
who just jumps down blindly hoping for the best,
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2762
der bare springer ned og håber på det bedste,
17:10
you might find yourself in a bit of a mess when you hit the ground.
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så kan man komme i noget være rod når man rammer jorden.
17:15
But if you're an optimistic penguin
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1889
Men hvis man er en optimistisk pingvin
17:17
who believes they can fly,
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1796
der tror på de kan flyve,
17:19
but then adjusts a parachute to your back
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2663
men justerer det ved at have en faldskærm på ryggen,
17:22
just in case things don't work out exactly as you had planned,
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3017
bare for det tilfælde at tingene ikke ender som planlagt,
17:25
you will soar like an eagle,
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vil man svæve som en ørn,
17:26
even if you're just a penguin.
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selvom man kun er en pingvin.
17:29
Thank you.
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Tak.
17:31
(Applause)
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(Bifald)
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