David Anderson: Your brain is more than a bag of chemicals

163,597 views ・ 2013-03-12

TED


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00:00
Translator: Joseph Geni Reviewer: Morton Bast
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Prevoditelj: Barbara Safaric Recezent: Vedrana Vučković Jakšić
00:15
So raise your hand if you know someone
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Dignite ruku ako znate nekog
00:19
in your immediate family or circle of friends
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u svojoj užoj obitelji ili krugu bliskih prijatelja
00:21
who suffers from some form of mental illness.
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tko pati od nekog oblika mentalne bolesti.
00:25
Yeah. I thought so. Not surprised.
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Da. Tako sam i mislio. Nisam iznenađen.
00:28
And raise your hand if you think that
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Također, dignite ruku ako mislite da
00:30
basic research on fruit flies has anything to do
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su istraživanja na vinskoj mušici u ikakvoj vezi
00:33
with understanding mental illness in humans.
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s razumijevanjem mentalnih bolesti kod ljudi.
00:37
Yeah. I thought so. I'm also not surprised.
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Da... Tako sam i mislio. Ponovno, nisam iznenađen.
00:40
I can see I've got my work cut out for me here.
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Vidim da kao publika predstavljate plodno tlo za mene.
00:43
As we heard from Dr. Insel this morning,
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Kao što ste jutros čuli od dr. Insel,
00:46
psychiatric disorders like autism, depression and schizophrenia
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psihijatrijski poremećaji kao što su autizam, depresija i shizofrenija
00:50
take a terrible toll on human suffering.
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u velikoj mjeri doprinose ljudskoj patnji.
00:53
We know much less about their treatment
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Malo nam je toga poznato o liječenju
00:56
and the understanding of their basic mechanisms
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i razumijevanju osnovnih mehanizama tih poremećaja
00:59
than we do about diseases of the body.
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u usporedbi s onim što znamo o fizičkim bolestima.
01:01
Think about it: In 2013,
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Razmislite malo o tome, u 2013. godini,
01:04
the second decade of the millennium,
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u drugom desetljeću ovoga milenija,
01:06
if you're concerned about a cancer diagnosis
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ako ste zabrinuti da bolujete od karcinoma
01:08
and you go to your doctor, you get bone scans,
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i odete liječniku, pregledaju vam kosti,
01:11
biopsies and blood tests.
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naprave biopsiju i krvne pretrage.
01:14
In 2013, if you're concerned about a depression diagnosis,
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U 2013. godini, ako ste zabrinuti da bolujete od depresije
01:18
you go to your doctor, and what do you get?
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i odete liječniku, što dobijete?
01:20
A questionnaire.
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Upitnik.
01:22
Now, part of the reason for this is that we have
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Jedan od razloga je taj što imamo
01:24
an oversimplified and increasingly outmoded view
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vrlo pojednostavljen i zastario pogled
01:28
of the biological basis of psychiatric disorders.
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na biološku osnovu psihijatrijskih poremećaja.
01:32
We tend to view them --
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Obično smatramo,
01:33
and the popular press aids and abets this view --
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i to je pogled koji se promovira i u medijima,
01:36
as chemical imbalances in the brain,
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da se radi o kemijskoj neravnoteži u mozgu,
01:39
as if the brain were some kind of bag of chemical soup
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kao da je mozak kotao kemijske juhe
01:42
full of dopamine, serotonin and norepinephrine.
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od dopamina, serotonina i noradrenalina.
01:47
This view is conditioned by the fact
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Takav stav posljedica je činjenice
01:49
that many of the drugs that are prescribed to treat these disorders,
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da mnogi lijekovi koji se prepisuju u liječenju tih poremećaja,
01:52
like Prozac, act by globally changing brain chemistry,
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kao što je Prozac, djeluju na principu mijenjanja "kemije mozga",
01:57
as if the brain were indeed a bag of chemical soup.
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kao da je mozak uistinu kotao kemijske juhe.
02:01
But that can't be the answer,
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Ali to ne može biti rješenje
02:03
because these drugs actually don't work all that well.
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jer ti lijekovi zapravo i ne djeluju tako dobro.
02:06
A lot of people won't take them, or stop taking them,
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Mnogi ih ne žele uzimati ili će ih prestati uzimati
02:09
because of their unpleasant side effects.
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zbog neugodnih nuspojava koje izazivaju.
02:12
These drugs have so many side effects
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Ti lijekovi imaju toliko nuspojava
02:14
because using them to treat a complex psychiatric disorder
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jer njihovo korištenje u liječenju složenih psihijatrijskih poremećaja
02:18
is a bit like trying to change your engine oil
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može se usporediti s mijenjanjem motornog ulja
02:21
by opening a can and pouring it all over the engine block.
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tako da otvorite limenku ulja i izlijete je preko cijelog motora.
02:25
Some of it will dribble into the right place,
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Nešto će u konačnici završiti na pravom mjestu,
02:27
but a lot of it will do more harm than good.
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ali većina će napraviti više štete nego koristi.
02:30
Now, an emerging view
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Novi pogled,
02:32
that you also heard about from Dr. Insel this morning,
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o kojem ste također čuli jutros od dr. Insel,
02:35
is that psychiatric disorders are actually
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jest taj da su psihijatrijski poremećaji zapravo
02:38
disturbances of neural circuits that mediate
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smetnje u neurološkim sklopovima koji sudjeluju u posredovanju
02:41
emotion, mood and affect.
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emocija, raspoloženja i afekata.
02:45
When we think about cognition,
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Kada govorimo o kogniciji,
02:47
we analogize the brain to a computer. That's no problem.
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poistovjećujemo mozak s računalom. To nije problem.
02:50
Well it turns out that the computer analogy
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Ali ispostavilo se da analogija s računalom
02:53
is just as valid for emotion.
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vrijedi i u slučaju emocija.
02:55
It's just that we don't tend to think about it that way.
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Samo ne razmišljamo o tome na taj način.
02:58
But we know much less about the circuit basis
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Malo nam je poznato o neurološkim sklopovima
03:01
of psychiatric disorders
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kao o osnovi psihijatrijskih poremećaja
03:03
because of the overwhelming dominance
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zbog velike dominacije
03:05
of this chemical imbalance hypothesis.
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spomenute hipoteze o kemijskoj neravnoteži.
03:09
Now, it's not that chemicals are not important
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Ne tvrdim da kemijske tvari nisu važne
03:12
in psychiatric disorders.
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u psihijatrijskim poremećajima.
03:14
It's just that they don't bathe the brain like soup.
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Stvar je u tome što one ne oplahnjuju mozak kao juha.
03:18
Rather, they're released in very specific locations
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Umjesto toga, otpuštaju se na vrlo određenim lokacijama
03:22
and they act on specific synapses
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i djeluju na određene sinapse
03:24
to change the flow of information in the brain.
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kako bi se promijenio dotok informacija u mozak.
03:28
So if we ever really want to understand
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Dakle, ako stvarno želimo razumjeti
03:30
the biological basis of psychiatric disorders,
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biološku osnovu psihijatrijskih poremećaja,
03:33
we need to pinpoint these locations in the brain
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moramo točno locirati mjesta u mozgu
03:36
where these chemicals act.
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na koja spomenute kemijske tvari djeluju.
03:38
Otherwise, we're going to keep pouring oil all over our mental engines
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Inače ćemo nastaviti prolijevati ulje po našim mentalnim motorima
03:41
and suffering the consequences.
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i trpjeti posljedice.
03:44
Now to begin to overcome our ignorance
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U nastojanju da prevladamo svoje neznanje
03:47
of the role of brain chemistry in brain circuitry,
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o ulozi kemije mozga u neurološkim sklopovima,
03:51
it's helpful to work on what we biologists call
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korisno je raditi na onome što mi biolozi nazivamo
03:54
"model organisms,"
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modelnim organizmima,
03:55
animals like fruit flies and laboratory mice,
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životinjama kao što su vinske mušice i laboratorijski miševi,
03:58
in which we can apply powerful genetic techniques
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pri čemu možemo primijeniti genetičke metode
04:02
to molecularly identify and pinpoint
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da identificiramo na molekularnoj razini i točno odredimo
04:06
specific classes of neurons,
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specifične klase neurona,
04:07
as you heard about in Allan Jones's talk this morning.
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kao što ste ujutro čuli u govoru Allana Jonesa.
04:10
Moreover, once we can do that,
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Štoviše, kad to postane moguće,
04:12
we can actually activate specific neurons
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moći ćemo i aktivirati specifične neurone
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or we can destroy or inhibit the activity of those neurons.
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ili ih uništiti ili blokirati njihovu aktivnost.
04:19
So if we inhibit a particular type of neuron,
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Dakle, ako blokiramo određeni tip neurona
04:22
and we find that a behavior is blocked,
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i odredimo da je neki obrazac ponašanja blokiran,
04:25
we can conclude that those neurons
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možemo zaključiti kako su upravo ti neuroni
04:27
are necessary for that behavior.
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potrebni za određeni obrazac ponašanja.
04:30
On the other hand, if we activate a group of neurons
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S druge strane, ako aktiviramo skupinu neurona
04:32
and we find that that produces the behavior,
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i otkrijemo da to uzrokuje novi obrazac ponašanja,
04:35
we can conclude that those neurons are sufficient for the behavior.
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možemo zaključiti da su ti neuroni dostatni za javljanje tog obrasca.
04:39
So in this way, by doing this kind of test,
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Dakle, na ovaj način, provodeći navedena testiranja
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we can draw cause and effect relationships
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možemo uspostaviti odnos uzorka i posljedice
04:46
between the activity of specific neurons
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između aktivnosti određenih neurona
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in particular circuits and particular behaviors,
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u pojedinim sklopovima i određenih obrazaca ponašanja,
04:51
something that is extremely difficult, if not impossible,
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nešto što je vrlo teško, ako ne i nemoguće,
04:53
to do right now in humans.
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u ovom trenutku kod ljudi.
04:58
But can an organism like a fruit fly, which is --
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No može li organizam kao što je vinska mušica, koja je --
05:01
it's a great model organism
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odličan modelni organizam
05:03
because it's got a small brain,
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zato što ima mali mozak,
05:06
it's capable of complex and sophisticated behaviors,
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sposobna je za složena i sofisticirana ponašanja,
05:10
it breeds quickly, and it's cheap.
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brzo se razmnožava i jeftina je...
05:13
But can an organism like this
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Može li nas takav organizam
05:15
teach us anything about emotion-like states?
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naučiti nešto o stanjima vezanima uz emocije?
05:18
Do these organisms even have emotion-like states,
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Imaju li ti organizmi uopće emocije
05:22
or are they just little digital robots?
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ili su samo nalik malim digitalnim robotima?
05:25
Charles Darwin believed that insects have emotion
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Charles Darwin vjerovao je da insekti imaju emocije
05:28
and express them in their behaviors, as he wrote
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i izražavaju ih svojim ponašanjem, kako je napisao
05:31
in his 1872 monograph on the expression of the emotions in man and animals.
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1872. godine u svojoj monografiji o izražavanju emocija kod ljudi i životinja.
05:36
And my eponymous colleague, Seymour Benzer, believed it as well.
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Isto je i vjerovao moj istoimeni kolega, Seymour Benzer.
05:40
Seymour is the man that introduced the use of drosophila
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Seymour je čovjek koji je uveo Drosophilu
05:43
here at CalTech in the '60s as a model organism
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kao modelni organizam ovdje na CalTech u 60-ima
05:47
to study the connection between genes and behavior.
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za istraživanje veze između gena i ponašanja.
05:50
Seymour recruited me to CalTech in the late 1980s.
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Seymour me zaposlio na CalTechu u kasnim 1980-ima.
05:54
He was my Jedi and my rabbi while he was here,
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Bio je moj Jedi i moj rabin kad je bio ovdje
05:58
and Seymour taught me both to love flies
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i Seymour me naučio kako voljeti mušice
06:01
and also to play with science.
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i istovremeno se igrati sa znanošću.
06:04
So how do we ask this question?
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Kako dakle postaviti to pitanje?
06:07
It's one thing to believe that flies have emotion-like states,
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Jedna je stvar vjerovati da mušice imaju emocije,
06:11
but how do we actually find out whether that's true or not?
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ali kako zapravo možemo saznati je li to istina?
06:14
Now, in humans we often infer emotional states,
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Kod ljudi, često zaključujemo o emocionalnom stanju,
06:18
as you'll hear later today, from facial expressions.
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kao što ćete čuti kasnije danas, na temelju izraza lica.
06:22
However, it's a little difficult to do that in fruit flies.
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Međutim, malo je teže napraviti isto s vinskim mušicama.
06:26
(Laughter)
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(smijeh)
06:29
It's kind of like landing on Mars
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To je kao da slijećete na Mars
06:32
and looking out the window of your spaceship
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i gledajući kroz prozor svemirskog broda
06:35
at all the little green men who are surrounding it
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na sve "male zelene" koji ga okružuju,
06:37
and trying to figure out, "How do I find out
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pokušavate shvatiti "Kako mogu saznati
06:40
if they have emotions or not?"
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imaju li oni emocije ili ne?"
06:42
What can we do? It's not so easy.
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Što možemo učiniti? Nije tako lagano.
06:45
Well, one of the ways that we can start
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Jedan od načina na koji možemo početi
06:48
is to try to come up with some general characteristics
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jest pokušati s nekim općim značajkama
06:52
or properties of emotion-like states
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ili obilježjima emocija,
06:56
such as arousal, and see if we can identify
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kao što je uzbuđenje, i vidjeti možemo li identificirati
06:59
any fly behaviors that might exhibit some of those properties.
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bilo koje ponašanje mušice koje pokazuje neka od tih obilježja.
07:04
So three important ones that I can think of
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Tri važna obilježja kojih se mogu sjetiti
07:07
are persistence, gradations in intensity, and valence.
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su upornost, gradacije u intenzitetu i valencija.
07:12
Persistence means long-lasting.
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Upornost u kontekstu dugotrajnog.
07:14
We all know that the stimulus that triggers an emotion
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Svi znamo da podražaj koji aktivira emociju
07:18
causes that emotion to last long after the stimulus is gone.
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uzrokuje trajanje emocije i nakon prestanka samog podražaja.
07:23
Gradations of intensity means what it sounds like.
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Gradacija intenziteta znači baš ono kao što i zvuči.
07:26
You can dial up the intensity or dial down the intensity of an emotion.
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Možete povisiti ili sniziti intenzitet emocija.
07:31
If you're a little bit unhappy, the corners of your mouth
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Ako ste pomalo nesretni, uglovi vaših usana
07:33
turn down and you sniffle,
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okrenu se prema dolje i šmrčete,
07:35
and if you're very unhappy, tears pour down your face
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a ako ste vrlo nesretni, lijete suze
07:38
and you might sob.
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i možda zajecate.
07:40
Valence means good or bad, positive or negative.
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Valencija znači dobro ili loše, pozitivno ili negativno.
07:44
So we decided to see if flies could be provoked into showing
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Odlučili smo vidjeti možemo li izazvati mušice da pokažu
07:49
the kind of behavior that you see
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neke od obrazaca ponašanja koja možete vidjeti
07:51
by the proverbial wasp at the picnic table,
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kod ose za stolom na pikniku,
07:54
you know, the one that keeps coming back to your hamburger
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znate, one koja se uporno vraća na vaš hamburger
07:57
the more vigorously you try to swat it away,
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što se više trudite otjerati je
07:59
and it seems to keep getting irritated.
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i čini se da je sve uzrujanija.
08:02
So we built a device, which we call a puff-o-mat,
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Sastavili smo uređaj, koji mi zovemo "puhomat",
08:05
in which we could deliver little brief air puffs to fruit flies
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kojim smo mogli isporučiti kratku stuju zraka usmjerenu na vinske mušice
08:10
in these plastic tubes in our laboratory bench
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u plastičnim cjevčicama u našem laboratoriju
08:12
and blow them away.
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te ih otpuhati.
08:14
And what we found is that if we gave these flies
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Doznali smo da ako izložimo mušice
08:17
in the puff-o-mat several puffs in a row,
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u "puhomatu" uzastopnim kratkim strujanjima zraka,
08:20
they became somewhat hyperactive
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one postanu, recimo, hiperaktivne
08:23
and continued to run around for some time after the air puffs actually stopped
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i nastave letjeti uokolo još neko vrijeme i nakon što je strujanje zraka prestalo
08:27
and took a while to calm down.
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te im je potrebno neko vrijeme da se smire.
08:30
So we quantified this behavior
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Kvantificirali smo to ponašanje
08:32
using custom locomotor tracking software
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prilagođenim programom za lokomotorno praćenje
08:35
developed with my collaborator Pietro Perona,
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razvijenim s mojim suradnikom Pietrom Peronom,
08:38
who's in the electrical engineering division here at CalTech.
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koji radi u elektrotehničkom odjelu ovdje na CalTechu.
08:42
And what this quantification showed us is that,
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Ta kvantifikacija pokazala nam je da
08:45
upon experiencing a train of these air puffs,
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nakon izlaganja kontinuiranim kratkim strujanjima zraka
08:48
the flies appear to enter a kind of state of hyperactivity
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mušice naizgled postanu hiperaktivne,
08:52
which is persistent, long-lasting,
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što je stabilno, dugotrajno stanje
08:55
and also appears to be graded.
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koje se također čini gradiranim.
08:57
More puffs, or more intense puffs,
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Više strujanja, ili intenzivnija strujanja,
09:00
make the state last for a longer period of time.
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uzrokuju dulje stanje hiperaktivnosti.
09:04
So now we wanted to try to understand something
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Zatim smo htjeli saznati nešto o
09:06
about what controls the duration of this state.
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načinu kontrole trajanja tog stanja.
09:10
So we decided to use our puff-o-mat
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Odlučili smo koristit naš "puhomat"
09:13
and our automated tracking software
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i automatizirani program za praćenje
09:15
to screen through hundreds of lines of mutant fruit flies
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za provjeru stotine linija mutanata vinske mušice da bismo vidjeli
09:19
to see if we could find any that showed abnormal responses to the air puffs.
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možemo li pronaći mutante koji pokazuju nenormalne odgovore na strujanja zraka.
09:24
And this is one of the great things about fruit flies.
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Jedna od odličnih stvari vezano uz vinsku mušicu.
09:26
There are repositories where you can just pick up the phone
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Postoje repozitoriji gdje možete samo okrenuti telefonski broj
09:29
and order hundreds of vials of flies of different mutants
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i naručiti stotine bočica s različitim mutantima vinske mušice,
09:32
and screen them in your assay and then find out
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analizirati ih i otkriti
09:35
what gene is affected in the mutation.
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koji je gen promijenjen mutacijom.
09:38
So doing the screen, we discovered one mutant
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Dakle, tijekom analize otkrili smo jednog mutanta
09:41
that took much longer than normal to calm down
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kojem je bilo potrebno mnogo dulje da se smiri
09:45
after the air puffs,
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nakon strujanja zraka
09:47
and when we examined the gene that was affected in this mutation,
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i kada smo provjerili gen koji je promijenjen tom mutacijom
09:51
it turned out to encode a dopamine receptor.
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ispostavilo se da taj gen kodira dopaminski receptor.
09:55
That's right -- flies, like people, have dopamine,
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Da, tako je - mušice, kao i ljudi, imaju dopamin,
09:58
and it acts on their brains and on their synapses
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koji djeluje na njihov mozak i njihove sinapse
10:00
through the same dopamine receptor molecules
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preko istih dopaminskih receptora
10:03
that you and I have.
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koje imamo i vi i ja.
10:05
Dopamine plays a number of important functions in the brain,
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Dopamin ima mnogo važnih funkcija u mozgu,
10:09
including in attention, arousal, reward,
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uključujući one vezane uz pozornost, uzbuđenje, nagradu,
10:12
and disorders of the dopamine system have been linked
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a poremećaji dopaminskog sustava povezani su
10:15
to a number of mental disorders including drug abuse,
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s brojnim mentalnim poremećajima uključujući zloupotrebu droga,
10:19
Parkinson's disease, and ADHD.
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Parkinsonovu bolest te ADHD (poremećaj pozornosti s hiperaktivnošću).
10:23
Now, in genetics, it's a little counterintuitive.
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U genetici to je pomalo protuintuitivno.
10:26
We tend to infer the normal function of something
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Zaključujemo o normalnoj funkciji nečega
10:29
by what doesn't happen when we take it away,
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na temelju onoga što se ne dogodi kada to oduzmemo,
10:33
by the opposite of what we see when we take it away.
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na temelju suprotnog od onog što vidimo kada to oduzmemo.
10:36
So when we take away the dopamine receptor
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Dakle, kada odstranimo domapinski receptor
10:39
and the flies take longer to calm down,
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i mušicama je potrebno više vremena da se smire,
10:41
from that we infer that the normal function of this receptor and dopamine
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zaključit ćemo da je normalna funkcija tog receptora i dopamina
10:45
is to cause the flies to calm down faster after the puff.
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vezana uz brže smirivanje mušica nakon što su izložene struji zraka.
10:49
And that's a bit reminiscent of ADHD,
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To pomalo podsjeća na ADHD,
10:52
which has been linked to disorders of the dopamine system in humans.
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koji je povezan s poremećajima dopaminskog sustava u ljudi.
10:56
Indeed, if we increase the levels of dopamine in normal flies
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Doista, ako povećamo razinu dopamina u normalnih mušica
11:01
by feeding them cocaine
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hraneći ih kokainom,
11:03
after getting the appropriate DEA license
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nakon što smo dobili odgovarajuću dozvolu od DEA-e
11:06
— oh my God -- (Laughter) —
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- o moj Bože - (smijeh)
11:10
we find indeed that these cocaine-fed flies
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došli smo do saznanja da se kokainom hranjene mušice
11:13
calm down faster than normal flies do,
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doista smire brže u usporedbi s normalnima,
11:16
and that's also reminiscent of ADHD,
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i to također podsjeća na ADHD,
11:19
which is often treated with drugs like Ritalin
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koji se često liječi lijekovima kao što su Ritalin
11:21
that act similarly to cocaine.
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koji djeluje na sličan način kao kokain.
11:24
So slowly I began to realize that what started out
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Tako sam polako počeo shvaćati da bi ono što smo započeli
11:27
as a rather playful attempt to try to annoy fruit flies
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kao prilično razigran pokušaj da uzrujamo vinske mušice
11:31
might actually have some relevance to a human psychiatric disorder.
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zapravo moglo biti važno za psihijatrijske poremećaje kod ljudi.
11:35
Now, how far does this analogy go?
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Što sve možemo obuhvatiti ovom analogijom?
11:37
As many of you know, individuals afflicted with ADHD
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Kao što mnogi od vas znaju, pojedinci koju boluju od ADHD-a
11:40
also have learning disabilities.
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također imaju i poteškoće u učenju.
11:43
Is that true of our dopamine receptor mutant flies?
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Vrijedi li isto i za naše mušice s mutiranim dopaminskim receptorom?
11:46
Remarkably, the answer is yes.
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Iznenađujuće, odgovor je da.
11:49
As Seymour showed back in the 1970s,
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Kao što je Seymour prezentirao u 1970-ima,
11:52
flies, like songbirds, as you just heard,
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mušice, poput ptica pjevica, kao što ste upravo čuli,
11:54
are capable of learning.
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imaju sposobnost učenja.
11:56
You can train a fly to avoid an odor, shown here in blue,
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Možete obučiti mušicu da izbjegava određeni miris, što je prikazano plavom bojom,
12:00
if you pair that odor with a shock.
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ako povežete taj miris sa šokom.
12:03
Then when you give those trained flies the chance to choose
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Kada date tim obučenim mušicama da biraju
12:06
between a tube with the shock-paired odor and another odor,
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između cijevi s mirisom koji je povezan sa šokom i nekim drugim mirisom,
12:09
it avoids the tube containing the blue odor that was paired with shock.
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izbjegavat će cjevčicu koja sadrži plavi miris koji je povezan sa šokom.
12:13
Well, if you do this test on dopamine receptor mutant flies,
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Ali ako provedete isti test na mušicama s mutiranim dopaminskim receptorom,
12:17
they don't learn. Their learning score is zero.
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one neće naučiti ništa. Konačna ocjena je nula.
12:19
They flunk out of CalTech.
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Izbačene su s CalTecha.
12:23
So that means that these flies have two abnormalities,
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Dakle, to znači da te mušice imaju dvije abnormalnosti,
12:28
or phenotypes, as we geneticists call them,
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ili fenotipa, kao što ih mi genetičari nazivamo,
12:31
that one finds in ADHD: hyperactivity and learning disability.
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koji su prisutni i kod ADHD-a: hiperaktivnost i poteškoće u učenju.
12:36
Now what's the causal relationship, if anything, between these phenotypes?
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Koja je uzročno-posljedična veza, ako postoji, između tih fenotipova?
12:41
In ADHD, it's often assumed that the hyperactivity
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Kod ADHD-a često se pretpostavlja da hiperaktivnost
12:45
causes the learning disability.
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uzrokuje poteškoće u učenju.
12:47
The kids can't sit still long enough to focus, so they don't learn.
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Djeca ne mogu biti mirna dovoljno dugo da se koncentriraju, pa tako ne mogu učiti.
12:50
But it could equally be the case that it's the learning disabilities
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Ali jednako bi tako mogao biti slučaj da teškoće u učenju
12:54
that cause the hyperactivity.
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uzrokuju hiperaktivnost.
12:55
Because the kids can't learn, they look for other things to distract their attention.
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Budući da djeca ne mogu učiti, traže druge stvari da im skrenu pozornost.
13:00
And a final possibility is that there's no relationship at all
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I posljednja je mogućnost da povezanost
13:03
between learning disabilities and hyperactivity,
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između poteškoća u učenju i hiperaktivnosti uopće ne postoji,
13:05
but that they are caused by a common underlying mechanism in ADHD.
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već da su uzrokovani zajedničkim temeljnim mehanizmom ADHD-a.
13:10
Now people have been wondering about this for a long time
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To je već dugo predmet rasprava vezano
13:13
in humans, but in flies we can actually test this.
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za ljude, ali kod mušica to možemo i testirati.
13:16
And the way that we do this is to delve deeply into the mind
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Način na koji to možemo učiniti jest zaviriti duboko u um
13:19
of the fly and begin to untangle its circuitry using genetics.
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mušice i početi raspetljavati sklopove pomoću genetike.
13:23
We take our dopamine receptor mutant flies
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Uzmemo mušice s mutiranim dopamintskim receptorom
13:26
and we genetically restore, or cure, the dopamine receptor
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i genetički obnovimo, ili izliječimo, dopaminski receptor
13:30
by putting a good copy of the dopamine receptor gene
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umetanjem dobre kopije gena za dopaminski receptor
13:34
back into the fly brain.
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u mozak mušice.
13:36
But in each fly, we put it back only into certain neurons
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Ali u svakoj ga mušici umetnemo jedino u određene neurone,
13:40
and not in others, and then we test each of these flies
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a u druge ne, i zatim analiziramo svaku od mušica
13:43
for their ability to learn and for hyperactivity.
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i njihovu sposobnost učenja i hiperaktivnost.
13:47
Remarkably, we find we can completely dissociate these two abnormalities.
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Izuzetno, spoznali smo da u potpunosti možemo razdvojiti te dvije anomalije.
13:52
If we put a good copy of the dopamine receptor back
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Ako stavimo dobru kopiju dopaminskog receptora u
13:54
in this elliptical structure called the central complex,
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eliptičnu strukturu zvanu središnji kompleks,
13:57
the flies are no longer hyperactive, but they still can't learn.
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mušice nisu više hiperaktivne, ali još nemaju sposobnost učenja.
14:01
On the other hand, if we put the receptor back in a different structure
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S druge strane, ako stavimo receptor u drugačiju strukturu,
14:04
called the mushroom body,
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prednji asocijativni centar,
14:06
the learning deficit is rescued, the flies learn well,
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počeškoće u učenju su otklonjene, mušice mogu učiti,
14:09
but they're still hyperactive.
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ali su i dalje hiperaktivne.
14:11
What that tells us is that dopamine
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To nam govori da dopamin
14:13
is not bathing the brain of these flies like soup.
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ne oplahnjuje mozak tih mušica kao juha.
14:16
Rather, it's acting to control two different functions
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Umjesto toga, on kontrolira dvije različite funkcije
14:19
on two different circuits,
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na dva različita sklopa,
14:21
so the reason there are two things wrong with our dopamine receptor flies
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pa razlog postojanja dviju stvari koje nisu u redu s mušicama s mutiranim dopaminskim receptorom
14:25
is that the same receptor is controlling two different functions
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leži u činjenici da jedan receptor kontrolira dvije različite funkcije
14:29
in two different regions of the brain.
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u dvije različite regije mozga.
14:32
Whether the same thing is true in ADHD in humans
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Vrijedi li ista stvar i za ADHD kod ljudi,
14:35
we don't know, but these kinds of results
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ne znamo, ali rezultati poput ovih
14:37
should at least cause us to consider that possibility.
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trebali bi nas barem potaknuti da razmotrimo tu mogućnost.
14:41
So these results make me and my colleagues more convinced than ever
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Dakle, ovi rezultati uvjerili su mene i moje kolege više nego ikad
14:45
that the brain is not a bag of chemical soup,
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da mozak nije samo kotao kemijske juhe
14:48
and it's a mistake to try to treat complex psychiatric disorders
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i da je pogrešno pokušavati liječiti složene psihijatrijske poremećaje
14:52
just by changing the flavor of the soup.
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mijenjajući samo okus juhe.
14:55
What we need to do is to use our ingenuity and our scientific knowledge
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Trebamo iskoristiti svoju domišljatost i svoje znanstvene spoznaje
14:59
to try to design a new generation of treatments
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te pokušati osmisliti novu generaciju tretmana
15:01
that are targeted to specific neurons and specific regions of the brain
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koji su usmjereni na određene neurone i specifične regije mozga
15:06
that are affected in particular psychiatric disorders.
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koji su pogođeni kod određenih psihijatrijskih poremećaja.
15:09
If we can do that, we may be able to cure these disorders
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Ako to možemo učiniti, mogli bismo izliječiti te bolesti
15:12
without the unpleasant side effects,
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bez neugodnih nuspojava,
15:14
putting the oil back in our mental engines,
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dolijevajući ulje u naše mentalne motore
15:17
just where it's needed. Thank you very much.
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točno tamo gdje je to potrebno. Puno hvala.
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