This is a thousand-year-old drawing of the brain. It's a diagram of the visual system. And some things look very familiar today. Two eyes at the bottom, optic nerve flowing out from the back. There's a very large nose that doesn't seem to be connected to anything in particular.
Ovo je crtež mozga star tisuću godina. To je graf optičkog sustava. A neke stvari danas izgledaju veoma poznato. Dva oka na dnu, optički živac proizlazi iz pozadine. Tu je jako velik nos koji, čini se, nije povezan s ničim posebnim.
And if we compare this to more recent representations of the visual system, you'll see that things have gotten substantially more complicated over the intervening thousand years. And that's because today we can see what's inside of the brain, rather than just looking at its overall shape.
Ako to usporedimo sa suvremenijim prikazima optičkog sustava, vidjet ćete da su se stvari jako zakomplicirale kroz proteklih tisuću godina. A to je zato što danas možemo vidjeti što je unutar mozga, a ne samo gledati njegov cjelokupni oblik.
Imagine you wanted to understand how a computer works and all you could see was a keyboard, a mouse, a screen. You really would be kind of out of luck. You want to be able to open it up, crack it open, look at the wiring inside. And up until a little more than a century ago, nobody was able to do that with the brain. Nobody had had a glimpse of the brain's wiring.
Zamislite da želite razumjeti kako kompjuter radi, a možete vidjeti samo tipkovnicu, miša i ekran. Zbilja ne biste imali sreće. Želite moći otvoriti ga, rastvoriti ga, razgledati ožičenje unutra. I sve do prije malo više od sto godina, nitko to nije mogao učiniti s mozgom. Nitko nije ni povirio u ožičenje mozga.
And that's because if you take a brain out of the skull and you cut a thin slice of it, put it under even a very powerful microscope, there's nothing there. It's gray, formless. There's no structure. It won't tell you anything.
I zato, ako izvadite mozak iz lubanje i odrežete tanak režanj, stavite ga čak i pod veoma snažan mikroskop, ondje nema ničega. Siv je, bez oblika. Nema strukture. Neće vam ništa reći.
And this all changed in the late 19th century. Suddenly, new chemical stains for brain tissue were developed and they gave us our first glimpses at brain wiring. The computer was cracked open.
A to se sve promijenilo krajem 19. stoljeća. Odjednom, razvijene su nove kemijske mrlje za tkivo mozga i dale su nam prve poglede na ožičenje mozga. Kompjuter je rastvoren.
So what really launched modern neuroscience was a stain called the Golgi stain. And it works in a very particular way. Instead of staining all of the cells inside of a tissue, it somehow only stains about one percent of them. It clears the forest, reveals the trees inside. If everything had been labeled, nothing would have been visible. So somehow it shows what's there.
Ono što je zbilja pokrenulo modernu neuroznanost je bila mrlja nazvana "Golgijeva mrlja". A radi na jedan poseban način. Umjesto da umrlja sve stanice unutar tkiva, ona nekako umrlja samo oko 1% njih. Ona rasčišćava šumu, otkriva stabla unutar nje. Ako je sve već označeno, ništa se ne bi vidjelo. Ali nekako pokazuje što je ondje.
Spanish neuroanatomist Santiago Ramon y Cajal, who's widely considered the father of modern neuroscience, applied this Golgi stain, which yields data which looks like this, and really gave us the modern notion of the nerve cell, the neuron. And if you're thinking of the brain as a computer, this is the transistor. And very quickly Cajal realized that neurons don't operate alone, but rather make connections with others that form circuits just like in a computer. Today, a century later, when researchers want to visualize neurons, they light them up from the inside rather than darkening them. And there's several ways of doing this. But one of the most popular ones involves green fluorescent protein. Now green fluorescent protein, which oddly enough comes from a bioluminescent jellyfish, is very useful. Because if you can get the gene for green fluorescent protein and deliver it to a cell, that cell will glow green -- or any of the many variants now of green fluorescent protein, you get a cell to glow many different colors.
Španjolski neuroanatomist, Santiago Ramon y Cajal, koji se smatra ocem moderne neuroznanosti, primjenio je tu Golgijevu mrlju, koja donosi podatke koji ovako izgledaju, i zbilja nam dao moderan pojam živčane stanice, neurona. A ako razmišljate o mozgu kao o kompjuteru, ovo je tranzistor. I Cajal je ubrzo shvatio da neuroni ne rade sami, već stvaraju veze s drugima i tvore krugove baš kao kod kompjutera. Danas, sto godina kasnije, kada znanstvenici žele vizualizirati neurone, posvijetle ih iznutra, umjesto da ih potamne. A postoji nekoliko načina na koje se to napravi. Ali jedan od najpopularnijih uključuje zeleni fluorescentni protein. Zeleni fluorescentni protein, čudno je to ¸što dolazi od bioluminiscentne meduze, veoma je koristan. Ako možete dobiti gen za zeleni fluorescentni protein i dopremiti ga do stanice, ta stanica će svijetliti zeleno - ili bilo koju drugu od mnogih varijacija zelenog fluorescentnog proteina, možete dobiti stanicu koja svijetli u mnogo različitih boja.
And so coming back to the brain, this is from a genetically engineered mouse called "Brainbow." And it's so called, of course, because all of these neurons are glowing different colors.
Vratimo se na mozak. Ovo je iz genetički stvorenog miša nazvanog "Moždana duga". A tako se, naravno, zove zato što svi ovi neuroni svijetle u različitim bojama.
Now sometimes neuroscientists need to identify individual molecular components of neurons, molecules, rather than the entire cell. And there's several ways of doing this, but one of the most popular ones involves using antibodies. And you're familiar, of course, with antibodies as the henchmen of the immune system. But it turns out that they're so useful to the immune system because they can recognize specific molecules, like, for example, the coat protein of a virus that's invading the body. And researchers have used this fact in order to recognize specific molecules inside of the brain, recognize specific substructures of the cell and identify them individually.
Ponekad neuroznanstvenici moraju identificirati pojedinačne molekularne sastavnice neurona, molekule, a ne cijele stanice. To se može napraviti na nekoliko načina, ali jedan od najpopularnijih uključuje korištenje antitijela. A vi ste, naravno, upoznati s antitijelima kao štitonošama imunosnog sustava. Ali ispada da su tako korisna imunosnom sustavu zato što mogu prepoznati određene molekule, kao, na primjer, protein s kodom virusa koji napada tijelo. I znanstvenici su iskoristili tu činjenicu kako bi prepoznali određene molekule unutar mozga, prepoznali određene podstrukture stanice i pojedinačno ih identificirali.
And a lot of the images I've been showing you here are very beautiful, but they're also very powerful. They have great explanatory power. This, for example, is an antibody staining against serotonin transporters in a slice of mouse brain.
I mnoge od slika koje sam vam ovdje pokazao su jako lijepe, ali isto tako su i vrlo snažne. Imaju veliku snagu objašnjenja. Ovo je, na primjer, mrlja na antitijelima nasuprot prenosiocima serotonina u režnju miševog mozga.
And you've heard of serotonin, of course, in the context of diseases like depression and anxiety. You've heard of SSRIs, which are drugs that are used to treat these diseases. And in order to understand how serotonin works, it's critical to understand where the serontonin machinery is. And antibody stainings like this one can be used to understand that sort of question.
A čuli ste za serotonin, naravno, u kontekstu bolesti kao što su depresija i tjeskoba. Čuli ste za SSRI lijekove, koji se koriste za liječenje tih bolesti. A kako bismo razumjeli kako serotonin djeluje, neophodno je razumjeti gdje se nalazi mehanizacija serotonina. Mrlje na antitijelima poput ove mogu se koristiti kako bi se razumjela ovakva pitanja.
I'd like to leave you with the following thought: Green fluorescent protein and antibodies are both totally natural products at the get-go. They were evolved by nature in order to get a jellyfish to glow green for whatever reason, or in order to detect the coat protein of an invading virus, for example. And only much later did scientists come onto the scene and say, "Hey, these are tools, these are functions that we could use in our own research tool palette." And instead of applying feeble human minds to designing these tools from scratch, there were these ready-made solutions right out there in nature developed and refined steadily for millions of years by the greatest engineer of all. Thank you. (Applause)
Želio bih završiti sa sljedećom misli: Zeleni fluorescentni protein i antitijela oboje su od samoga početka posve prirodni proizvodi. Razvila ih je priroda kako bi meduza svijetlila zeleno iz tko zna kojeg razloga, ili da bi se otkrio protein s kodom virusa koji napada tijelo, na primjer. A tek mnogo kasnije su se na sceni pojavili znanstvenici i rekli: "Hej, ovo je alat, to su funkcije koje bismo mogli koristiti u vlastitoj istraživačkoj paleti alata." I umjesto da uposlimo nejake ljudske umove da osmisle ove alate iz ničega, postojala su ova gotova rješenja negdje u prirodi koje je milijunima godina neprestano razvijao i usavršavao najveći inžinjer od svih. Hvala. (Pljesak)