Is marijuana bad for your brain? - Anees Bahji

9,898,357 views ・ 2019-12-02

TED-Ed


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Prevoditelj: Mirela Ivoš Recezent: Sanda L
00:06
In 1970,
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1970. godine marihuana je klasificirana kao droga broj jedan u SAD-u,
00:07
marijuana was classified as a schedule 1 drug in the United States:
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00:13
the strictest designation possible,
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najstroža moguća oznaka,
00:15
meaning it was completely illegal and had no recognized medical uses.
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što znači da je bila potpuno ilegalna, a njen medicinski značaj nije bio prepoznat.
00:20
For decades, this view persisted
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Desetljećima se ovo stajalište održalo
00:23
and set back research on the drug's mechanisms and effects.
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i sputavalo istraživanja mehanizama i učinaka droge.
00:28
Today, marijuana’s therapeutic benefits are widely acknowledged,
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Danas su terapeutske koristi marihuane široko priznate
00:33
and some nations have legalized medical use
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i neke su države legalizirale njenu medicinsku uporabu ili tome teže.
00:36
or are moving in that direction.
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00:38
But a growing recognition for marijuana’s medical value
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Ali povećano priznanje medicinske koristi marihuane ne odgovara na pitanje:
00:42
doesn’t answer the question:
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00:44
is recreational marijuana use bad for your brain?
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"Je li rekreacijska upotreba marihuane loša za tvoj mozak?"
00:49
Marijuana acts on the body’s cannabinoid system,
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Marihuana utječe na kanabinoidni tjelesni sustav,
00:52
which has receptors all over the brain and body.
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koji ima receptore u cijelom mozgu i tijelu.
00:56
Molecules native to the body, called endocannabinoids,
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Prirodne molekule u tijelu, zvane endokanabinoidi,
01:01
also act on these receptors.
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također utječu na te receptore.
01:03
We don’t totally understand the cannabinoid system,
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Ne razumijemo u potpunosti kanabinoidni sustav,
01:07
but it has one feature that provides a big clue to its function.
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ali ima jednu značajku koja pruža veliki uvid u njegovu funkciju.
01:12
Most neurotransmitters travel from one neuron to the next
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Većina neurotransmitera putuje od jednog do drugog neurona
01:15
through a synapse to propagate a message.
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kroz sinapsu kako bi širili poruke.
01:19
But endocannabinoids travel in the opposite direction.
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Ali endokanabinoidi putuju u suprotnom smjeru.
01:23
When a message passes from the one neuron to the next,
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Kada se poruka prenese od jednog do drugog neurona,
01:26
the receiving neuron releases endocannabinoids.
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prijemni neuron oslobađa endokanabinoide.
01:30
Those endocannabinoids travel backward
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Ti endokanabinoidi putuju nazad utječući na neuron koji šalje poruku -
01:33
to influence the sending neuron—
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01:35
essentially giving it feedback from the receiving neuron.
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ustvari mu dajući povratne informacije prijemnog neurona.
01:40
This leads scientists to believe that the endocannabinoid system
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To znanstvenike dovodi do uvjerenja da endokanabinoidni sustav
01:44
serves primarily to modulate other kinds of signals—
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primarno služi moduliranju drugih vrsta signala,
01:48
amplifying some and diminishing others.
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pojačavajući neke i smanjujući druge.
01:51
Feedback from endocannabinoids slows down rates of neural signaling.
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Povratne informacije endokanabinoida usporavaju stope neuronske signalizacije.
01:57
That doesn’t necessarily mean
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To ne znači nužno da se usporavaju ponašanje ili percepcija.
01:59
it slows down behavior or perception, though.
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02:01
For example, slowing down a signal that inhibits smell
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Naprimjer, usporavanje signala koji inhibira mirise
02:05
could actually make smells more intense.
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zapravo može napraviti mirise intenzivnijima.
02:09
Marijuana contains two main active compounds,
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Marihuana sadrži dva glavna aktivna spoja,
02:13
tetrahydrocannabinol or THC, and cannabidiol, or CBD.
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tetrahidrokanabinol, ili THC, i kanabidiol, ili CBD.
02:21
THC is thought to be primarily responsible for marijuana’s psychoactive effects
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THC se smatra primarno odgovornim za psihoaktivne učinke marihuane
02:27
on behavior, cognition, and perception,
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na ponašanje, kogniciju i percepciju,
02:30
while CBD is responsible for the non-psychoactive effects.
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dok je CBD odgovoran za nepsihoaktivne učinke.
02:35
Like endocannabinoids,
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Poput endokanabinoida,
02:37
THC slows down signaling by binding to cannabinoid receptors.
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THC usporava signaliziranje vezujući se za kanabinoidne receptore.
02:43
But it binds to receptors all over this sprawling, diffuse system
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Ali on se veže za receptore u cijelom ovom širokom, difuznom sustavu odjednom,
02:47
at once,
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02:48
whereas endocannabinoids are released in a specific place
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dok se endokanabinoidi otpuštaju na određenom mjestu
02:52
in response to a specific stimulus.
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kao odgovor na određeni podražaj.
02:55
This widespread activity coupled with the fact
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Ova rasprostranjena aktivnost povezana s činjenicom da kanabinoidni sustav
02:58
that the cannabinoid system indirectly affects many other systems,
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neizravno utječe na mnoge druge sustave
03:02
means that each person’s particular brain chemistry, genetics,
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znači da specifični kemijski sastav mozga, genetika pojedinca
03:06
and previous life experience
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te njegovo prethodno životno iskustvo značajno određuju kako će iskusiti drogu.
03:08
largely determine how they experience the drug.
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03:11
That’s true much more so with marijuana than with other drugs
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To se u većoj mjeri odnosi na marihuanu nego ostale droge,
03:16
that produce their effects through one or a few specific pathways.
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koje svoje učinke iskazuju na jedan ili više specifičnih načina.
03:20
So the harmful effects, if any, vary considerably from person to person.
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Tako štetni utjecaji, ako ikoji, značajno variraju od osobe do osobe.
03:26
And while we don’t know how exactly how marijuana
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I iako ne znamo kako točno marihuana
03:28
produces specific harmful effects,
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izaziva određene negativne učinke,
03:31
there are clear risk factors that can increase peoples’ likelihood
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postoje izvjesni rizični faktori koji mogu povećati vjerojatnost
03:34
of experiencing them.
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da će ih osobe doživjeti.
03:37
The clearest risk factor is age.
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Najizvjesniji rizični faktor je dob.
03:40
In people younger than 25,
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Kod ljudi mlađih od 25, kanabinoidni su receptori koncentriraniji
03:42
cannabinoid receptors are more concentrated in the white matter
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u bijeloj tvari nego kod ljudi starijih od 25.
03:46
than in people over 25.
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03:48
The white matter is involved in communication,
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Bijela tvar uključena je u komunikaciju,
03:51
learning, memory, and emotions.
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učenje, pamćenje i emocije.
03:54
Frequent marijuana use
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Učestalo korištenje marihuane može omesti razvoj sustava bijele tvari
03:56
can disrupt the development of white matter tracts,
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03:59
and also affect the brain’s ability to grow new connections.
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i utjecati na sposobnost mozga da stvara nove veze.
04:03
This may damage long-term learning ability and problem solving.
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To može oštetiti sposobnost dugoročnog učenja i rješavanja problema.
04:08
For now, it’s unclear how severe this damage can be
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Zasad, nije jasno koliko ozbiljno ovo oštećenje može biti ni je li reverzibilno.
04:11
or whether it’s reversible.
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Čak među mladim ljudima, rizik je veći što je osoba mlađa -
04:13
And even among young people,
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04:14
the risk is higher the younger someone is—
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04:17
much higher for a 15 year old than a 22 year old, for instance.
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puno viši za osobe od 15 nego, primjerice, za osobe od 22 godine.
04:22
Marijuana can also cause hallucinations or paranoid delusions.
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Marihuana također može uzrokovati halucinacije ili paranoidne deluzije.
04:27
Known as marijuana-induced psychosis,
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Poznat kao psihoza izazvana marihuanom,
04:29
these symptoms usually subside when a person stops using marijuana.
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ovaj skup simptoma obično jenjava kad osoba prestane uzimati marihuanu.
04:33
But in rare cases, psychosis doesn’t subside,
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Ali u rijetkim slučajevima, psihoza ne prestaje,
04:37
instead unmasking a persistent psychotic disorder.
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nego otkriva trajni psihotični poremećaj u podlozi.
04:41
A family history of psychotic disorders, like schizophrenia,
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Obiteljska povijest psihotičnih poremećaja poput shizofrenije je najizvjesniji,
04:46
is the clearest, though not the only, risk factor for this effect.
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ali ne i jedini rizični faktor ovakvog učinka.
04:49
Marijuana-induced psychosis is also more common among young adults,
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Psihoza izazvana marihuanom također je češća među mladim odraslim osobama,
04:53
though it’s worth noting that psychotic disorders
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iako vrijedi napomenuti da se psihotični poremećaji
04:56
usually surface in this age range anyway.
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i inače u ovoj dobi počinju iskazivati.
04:59
What’s unclear in these cases is whether the psychotic disorder
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Ono što ostaje nejasno u ovim slučajevima jest bi li se psihotični poremećaj
05:03
would have appeared without marijuana use—
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pojavio i da osoba nije uzimala marihuanu -
05:05
whether marijuana use triggers it early,
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je li marihuana okidač za ranije pojavljivanje,
05:07
is a catalyst for a tipping point that wouldn’t have been crossed otherwise,
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katalizator za prelaženje linije koja se u suprotnom ne bi prešla,
05:12
or whether the reaction to marijuana is merely an indication
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ili je reakcija na marihuanu samo indikator
05:15
of an underlying disorder.
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poremećaja u podlozi.
05:18
In all likelihood, marijuana’s role varies from person to person.
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U svakom slučaju, uloga marihuane varira od osobe do osobe.
05:23
At any age, as with many other drugs,
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U svakoj dobi, kao i s mnogim drugim drogama,
05:25
the brain and body
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mozak i tijelo postaju manje osjetljivi na marihuanu nakon ponovljene upotrebe,
05:27
become less sensitive to marijuana after repeated uses,
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05:31
meaning it takes more to achieve the same effects.
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što znači da je potrebno više za postizanje istih učinaka.
05:35
Fortunately, unlike many other drugs,
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Nasreću, za razliku od drugih droga,
05:37
there’s no risk of fatal overdose from marijuana,
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ne postoji rizik od predoziranja marihuanom,
05:41
and even heavy use doesn’t lead to debilitating
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i čak i teška uporaba marihuane ne dovodi do iscrpljenja
05:44
or life-threatening withdrawal symptoms if use stops.
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ili po život opasnih simptoma ustezanja po prestanku uporabe.
05:48
There are more subtle forms of marijuana withdrawal, though,
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Doduše, postoje suptilniji oblici ustezanja od marihuane,
05:52
including sleep disturbances, irritability, and depressed mood,
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uključujući poremećaje spavanja, iritabilnost i depresivno raspoloženje,
05:56
which pass within a few weeks of stopping use.
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koji se povlače kroz nekoliko tjedana od prestanka uporabe.
06:00
So is marijuana bad for your brain?
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Dakle, je li marihuana loša za tvoj mozak?
06:03
It depends who you are.
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Ovisi o tome tko si ti.
06:05
But while some risk factors are easy to identify,
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Ali iako su neki rizični faktori lakši za odrediti, drugi nisu dobro razumljivi,
06:08
others aren’t well understood—
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06:11
which means there’s still some possibility of experiencing negative effects,
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što znači da i dalje postoji mogućnost doživljavanja negativnih učinaka,
06:16
even if you don’t have any of the known risk factors.
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čak i ako nemaš nijedan poznati rizični faktor.
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