ABOUT THE SPEAKER
Sarah-Jayne Blakemore - Cognitive Neuroscientist
Sarah-Jayne Blakemore studies the social brain -- the network of brain regions involved in understanding other people -- and how it develops in adolescents.

Why you should listen

Remember being a teenager? Rocked internally with hormones, outwardly with social pressures, you sometimes wondered what was going on in your head. So does Sarah-Jayne Blakemore. And what she and others in her field are finding is: The adolescent brain really is different.

New brain imaging research and clever experiments are revealing how the cortex develops -- the executive part of the brain that handles things like planning, self-awareness, analysis of consequences and behavioral choices. It turns out that these regions develop more slowly during adolescence, and in fascinating ways that relate to risk-taking, peer pressure and learning.

Which leads to a bigger question: How can we better target education to speak to teenagers' growing, changing brains?

More profile about the speaker
Sarah-Jayne Blakemore | Speaker | TED.com
TEDGlobal 2012

Sarah-Jayne Blakemore: The mysterious workings of the adolescent brain

Sarah-Jayne Blakemore: Os misteriosos mecanismos do cerebro adolescente

Filmed:
3,041,951 views

Por que os adolescentes parecen ser máis impulsivos e ter menos conciencia de si mesmos ca os adultos? A neurocientífica cognitiva Sarah-Jayne Blakermore compara o córtex prefrontal de adolescentes e adultos, para mostrarnos como o crecemento e desenvolvemento cerebral dan conta da típica conduta da "mocidade".
- Cognitive Neuroscientist
Sarah-Jayne Blakemore studies the social brain -- the network of brain regions involved in understanding other people -- and how it develops in adolescents. Full bio

Double-click the English transcript below to play the video.

00:16
Fifteen years ago, it was widely assumed
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Hai 15 anos, pensábase que
00:19
that the vast majority of brain development
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a maior parte do desenvolvemento cerebral
00:21
takes place in the first few years of life.
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tiña lugar nos primeiros anos de vida.
00:24
Back then, 15 years ago, we didn't have the ability
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Daquela, hai 15 anos, non eramos quen
00:27
to look inside the living human brain
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de mirar dentro do cerebro humano vivo
00:29
and track development across the lifespan.
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e observar os seus
cambios ao longo da vida.
00:32
In the past decade or so, mainly due to advances
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Na última década, grazas aos avances
00:36
in brain imaging technology
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nas técnicas de neuroimaxe cerebral
00:37
such as magnetic resonance imaging, or MRI,
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como a resonancia magnética ou RM,
00:40
neuroscientists have started to look inside the living
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os neurocientíficos
comezaron a explorar en vivo
00:43
human brain of all ages, and to track changes
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cerebros de todas as idades e a seguir
00:46
in brain structure and brain function,
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os cambios na estrutura
e na función cerebral.
00:49
so we use structural MRI if you'd like to take a snapshot,
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Cando queremos facer
unha foto de alta resolución
00:52
a photograph, at really high resolution of the inside
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do cerebro humano vivo, usamos a RM
00:55
of the living human brain, and we can ask questions like,
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e así podemos facer preguntas como:
00:59
how much gray matter does the brain contain,
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canta materia gris contén o cerebro
01:01
and how does that change with age?
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e como cambia coa idade?
01:03
And we also use functional MRI, called fMRI,
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Tamén usamos a RM funcional ou RMf,
01:07
to take a video, a movie, of brain activity
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para gravar un vídeo, unha película
da actividade cerebral
01:10
when participants are taking part in some kind of task
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cando alguén está a facer algunha tarefa
01:13
like thinking or feeling or perceiving something.
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como pensar ou sentir ou percibir algo.
01:16
So many labs around the world are involved in this kind
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Moitos laboratorios do mundo están a facer
este tipo de investigación,
así que temos unha imaxe
01:19
of research, and we now have a really rich
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moi completa de como
se desenvolve o cerebro humano
01:21
and detailed picture of how the living human brain develops,
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01:24
and this picture has radically changed the way
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e esa imaxe cambiou moito
01:27
we think about human brain development
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o noso xeito de pensar
sobre o desenvolvemento
01:30
by revealing that it's not all over in early childhood,
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ao mostrar que non todo
remata na infancia,
01:33
and instead, the brain continues to develop
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senón que continúa
ao longo da adolescencia
01:35
right throughout adolescence and into the '20s and '30s.
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ata ben entrados os 20 - 30 anos.
01:40
So adolescence is defined as the period of life that starts
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A adolescencia é a etapa que
comeza cos cambios
01:43
with the biological, hormonal, physical changes of puberty
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biolóxicos, hormonais e
físicos da puberdade e
01:48
and ends at the age at which an individual attains
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finaliza á idade na que a persoa
01:51
a stable, independent role in society.
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acada un posto estable e
independente na sociedade.
01:55
(Laughter)
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(Risas)
01:56
It can go on a long time. (Laughter)
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Pode alongarse moito tempo. (Risas)
01:59
One of the brain regions that changes most dramatically
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Unha das rexións que máis cambia durante
02:02
during adolescence is called prefrontal cortex.
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a adolescencia é o córtex prefrontal.
02:05
So this is a model of the human brain,
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Aquí teñen unha maqueta do cerebro humano,
02:08
and this is prefrontal cortex, right at the front.
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e aquí, diante, está o córtex prefrontal.
02:11
Prefrontal cortex is an interesting brain area.
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O córtex prefrontal é moi interesante.
Proporcionalmente é meirande nos humanos
que en calquera outra especie,
02:14
It's proportionally much bigger in humans than
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02:17
in any other species, and it's involved in a whole range of
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e está implicado nunha morea de
funcións cognitivas de alto nivel,
02:21
high level cognitive functions, things like decision-making,
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como a toma de decisións, a planificación,
planear que imos facer mañá
ou a próxima semana
02:24
planning, planning what you're going to do tomorrow
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ou o próximo ano,
inhibir condutas inapropiadas,
02:26
or next week or next year, inhibiting
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02:29
inappropriate behavior, so stopping yourself saying
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como frearnos antes de dicir unha grosería
02:31
something really rude or doing something really stupid.
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ou facer unha estupidez.
Está tamén implicado
na interacción social,
02:34
It's also involved in social interaction,
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02:36
understanding other people, and self-awareness.
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en comprender aos outros,
e na autoconciencia.
02:39
So MRI studies looking at the development of this region
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Os estudos con RM teñen amosado que
02:42
have shown that it really undergoes dramatic development
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esta rexión sofre un cambio notable
02:45
during the period of adolescence.
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durante a adolescencia.
02:48
So if you look at gray matter volume, for example,
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Se observamos nesta figura os cambios
02:51
gray matter volume across age from age four to 22 years
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no volume de materia gris,
entre os 4 e os 22 anos,
02:55
increases during childhood, which is what you can see
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vese que aumenta durante a infancia,
02:58
on this graph. It peaks in early adolescence.
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e chega ao seu pico na adolescencia.
03:02
The arrows indicate peak gray matter volume
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As frechas sinalan o pico
de volume de materia gris
03:04
in prefrontal cortex. You can see that that peak happens
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no córtex prefrontal.
Os nenos acadan o pico
03:08
a couple of years later in boys relative to girls,
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un par de anos máis tarde cás nenas,
03:11
and that's probably because boys go through puberty
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probablemente porque, de media, acadan
03:13
a couple of years later than girls on average,
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a puberdade un par de anos
máis tarde ca elas.
03:15
and then during adolescence, there's a significant decline
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E durante a adolescencia
hai un declive significativo
03:19
in gray matter volume in prefrontal cortex.
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no volume de materia
gris no córtex prefrontal.
Podería parecer algo malo,
pero en realidade
03:21
Now that might sound bad, but actually this is
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03:23
a really important developmental process, because
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trátase dun proceso moi importante
do desenvolvemento,
03:26
gray matter contains cell bodies and connections
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porque a materia gris
contén corpos celulares
03:31
between cells, the synapses, and this decline
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e conexións entre células,
as sinapses, e este declive
03:34
in gray matter volume during prefrontal cortex
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no volume de materia gris
no córtex prefrontal
03:37
is thought to correspond to synaptic pruning,
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responde á poda sináptica,
03:40
the elimination of unwanted synapses.
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á eliminación das sinapses irrelevantes.
03:42
This is a really important process. It's partly dependent
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Este é un proceso moi importante.
03:45
on the environment that the animal or the human is in,
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Depende en parte do ambiente
no que un se desenvolve.
03:48
and the synapses that are being used are strengthened,
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As sinapses que están a usarse vense
03:52
and synapses that aren't being used
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fortalecidas e as que non se usan,
03:54
in that particular environment are pruned away.
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nese ambiente particular, pódanse.
03:56
You can think of it a bit like pruning a rosebush.
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Poden velo como a poda dunha roseira.
03:58
You prune away the weaker branches so that
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Pódanse as ramas febles para que
04:01
the remaining, important branches, can grow stronger,
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as que quedan, as importantes,
crezan robustas e
04:04
and this process, which effectively fine-tunes brain tissue
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este proceso, que axusta
eficazmente o tecido cerebral
04:08
according to the species-specific environment,
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ao ambiente específico de cada especie,
04:11
is happening in prefrontal cortex and in other brain regions
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ocorre no córtex prefrontal
e noutras rexións cerebrais
04:14
during the period of human adolescence.
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durante a etapa da adolescencia.
04:17
So a second line of inquiry that we use to track changes
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Unha segunda liña
de investigación para explorar
04:21
in the adolescent brain is using functional MRI
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os cambios no cerebro adolescente
é usar a RM funcional
04:24
to look at changes in brain activity across age.
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para ver como cambia
a actividade cerebral coa idade.
Dareilles un exemplo do meu laboratorio.
04:28
So I'll just give you an example from my lab.
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04:29
So in my lab, we're interested in the social brain, that is
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Estamos interesados no cerebro social,
04:33
the network of brain regions that we use to understand
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na rede de rexións cerebrais que usamos
04:36
other people and to interact with other people.
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para comprender aos outros
e interactuar con eles.
04:39
So I like to show a photograph of a soccer game
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Voulles mostrar unha foto
dun partido de fútbol
04:43
to illustrate two aspects of how your social brains work.
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para ilustrar dous aspectos do modo
en que traballa o cerebro social.
Este é o partido de fútbol. (Risas)
04:47
So this is a soccer game. (Laughter)
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04:48
Michael Owen has just missed a goal, and he's lying
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Michael Owen acaba de fallar un gol
04:51
on the ground, and the first aspect of the social brain
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e está tirado no céspede.
E o primeiro aspecto
04:54
that this picture really nicely illustrates is how automatic
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que ilustra tan ben esta foto
é o automáticas
04:57
and instinctive social emotional responses are,
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e instintivas que son as
respostas emocionais sociais,
de xeito que unha décima de segundo
despois de que fallara o gol,
05:00
so within a split second of Michael Owen missing this goal,
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todo o mundo está a facer
o mesmo xesto cos brazos
05:03
everyone is doing the same thing with their arms
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05:05
and the same thing with their face, even Michael Owen
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e coa cara, mesmo Michael
Owen, tirado no céspede,
05:06
as he slides along the grass, is doing the same thing
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fai o mesmo cos brazos
05:08
with his arms, and presumably has a similar
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e probablemente ten
a mesma expresión facial.
05:11
facial expression, and the only people who don't
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As únicas persoas que non o fan
05:13
are the guys in yellow at the back — (Laughs) —
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son os mozos de amarelo do fondo. (Risas)
05:16
and I think they're on the wrong end of the stadium,
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Creo que se equivocaron de bancada,
05:19
and they're doing another social emotional response
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e están a mostrar outra resposta emocional
05:21
that we all instantly recognize, and that's the second aspect
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que todos recoñecemos ao momento.
05:23
of the social brain that this picture really nicely illustrates,
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Este é o segundo aspecto do cerebro social
que ilustra tan ben esta foto,
05:27
how good we are at reading other people's behavior,
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o bos que somos lendo
a conduta dos demais,
05:30
their actions, their gestures, their facial expressions,
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as súas accións, xestos,
expresións faciais,
05:33
in terms of their underlying emotions and mental states.
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en termos dos estados mentais
e as emocións subxacentes.
05:37
So you don't have to ask any of these guys.
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Non precisamos falar con eses mozos.
05:39
You have a pretty good idea of what they're feeling
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Facémonos unha idea do que están a sentir
05:41
and thinking at this precise moment in time.
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e a pensar nese momento.
E niso é no que estamos
interesados no meu laboratorio.
05:44
So that's what we're interested in looking at in my lab.
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05:46
So in my lab, we bring adolescents and adults into the lab
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Traemos a adolescentes e a adultos
05:49
to have a brain scan, we give them some kind of task
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para facerlles un escáner,
pedímoslles que fagan
05:52
that involves thinking about other people, their minds,
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algunha tarefa na que teñan que pensar
05:55
their mental states, their emotions, and one of the findings
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sobre os estados mentais
e as emocións doutras persoas,
05:58
that we've found several times now, as have other labs
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e un dos achados
que atopamos repetidamente,
06:01
around the world, is part of the prefrontal cortex called
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como noutros laboratorios do mundo,
06:04
medial prefrontal cortex, which is shown in blue on the slide,
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ten que ver co córtex prefrontal medial,
06:07
and it's right in the middle of prefrontal cortex
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en azul na diapositiva,
unha rexión situada
06:10
in the midline of your head.
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xusto na liña media da cabeza.
06:12
This region is more active in adolescents when they make
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Esta rexión está máis activa
nos adolescentes que nos adultos
cando toman decisións sociais
e pensan sobre outros.
06:16
these social decisions and think about other people
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06:18
than it is in adults, and this is actually a meta-analysis
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Trátase do resultado dunha metaanálise
06:20
of nine different studies in this area from labs around
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de 9 estudos diferentes de laboratorios
06:24
the world, and they all show the same thing, that activity
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de todo o mundo, e todos mostran o mesmo,
06:26
in this medial prefrontal cortex area decreases
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esa actividade no córtex
prefrontal medial
06:30
during the period of adolescence.
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diminúe durante a adolescencia.
06:32
And we think that might be because adolescents and adults
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Pensamos que responde a
que adolescentes e adultos
06:35
use a different mental approach, a different
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usan unha estratexia cognitiva distinta
06:37
cognitive strategy, to make social decisions,
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para tomar decisións sociais e
06:41
and one way of looking at that is to do behavioral studies
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para comprobalo
traemos á xente ao noso laboratorio
06:44
whereby we bring people into the lab and we give them
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e pedímoslles unha tarefa condutual.
06:46
some kind of behavioral task, and I'll just give you
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Voulles dar un exemplo
06:49
another example of the kind of task that we use in my lab.
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do tipo de tarefa que
usamos no meu laboratorio.
06:52
So imagine that you're the participant in one of our
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Imaxinen que participan
nun dos nosos experimentos.
06:55
experiments. You come into the lab,
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Veñen ao laboratorio
06:56
you see this computerized task.
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e ven esta tarefa no ordenador.
06:59
In this task, you see a set of shelves.
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Poden ver que hai uns estantes.
07:02
Now, there are objects on these shelves, on some of them,
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Nalgúns deles hai obxectos,
07:05
and you'll notice there's a guy standing behind the set
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e fíxense que hai
un tipo detrás dos estantes,
07:08
of shelves, and there are some objects that he can't see.
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e hai obxectos que non pode ver.
07:11
They're occluded, from his point of view, with a kind of
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Están ocultos, dende a súa perspectiva,
07:13
gray piece of wood.
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cunha peza de madeira gris.
07:16
This is the same set of shelves from his point of view.
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Estes son os mesmos estantes
dende a súa perspectiva.
07:20
Notice that there are only some objects that he can see,
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Fíxense que el
só pode ver algúns obxectos,
07:23
whereas there are many more objects that you can see.
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e que vostedes poden ver moitos máis.
07:25
Now your task is to move objects around.
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O que teñen que facer é mover os obxectos.
07:28
The director, standing behind the set of shelves,
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O director, situado detrás dos estantes,
07:30
is going to direct you to move objects around,
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diralles a onde movelos,
pero lembren:
non lles vai pedir que movan
07:33
but remember, he's not going to ask you to move objects
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07:35
that he can't see. This introduces a really interesting
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obxectos que el non pode ver.
Isto é interesante,
porque hai un certo conflito
07:38
condition whereby there's a kind of conflict
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07:41
between your perspective and the director's perspective.
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entre a súa perspectiva e a do director.
Imaxinen que lles di que movan
o camión de arriba cara á esquerda.
07:44
So imagine he tells you to move the top truck left.
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Hai tres camións.
Instintivamente irán polo branco,
07:47
There are three trucks there. You're going to instinctively
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07:49
go for the white truck, because that's the top truck
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porque é o que está máis arriba
07:51
from your perspective, but then you have to remember,
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dende a súa perspectiva,
pero entón lembran
07:54
"Oh, he can't see that truck, so he must mean
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"Ah, el non pode ver ese camión,
07:56
me to move the blue truck," which is the top truck
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así que ten que referirse ao azul",
07:59
from his perspective. Now believe it or not,
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o máis alto dende a perspectiva del.
Créanme ou non, adultos sans
e intelixentes coma vostedes
08:01
normal, healthy, intelligent adults like you make errors
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08:04
about 50 percent of the time on that kind of trial.
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cometen erros un 50%
das veces nestes ensaios.
08:08
They move the white truck instead of the blue truck.
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Moven o camión branco no canto do azul.
08:10
So we give this kind of task to adolescents and adults,
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Pasámoslles a tarefa a mozos e adultos
e incluímos unha condición de control
08:14
and we also have a control condition
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08:15
where there's no director and instead we give people a rule.
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na que en vez do director
dabámoslles unha regra.
08:19
We tell them, okay, we're going to do exactly the same thing
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Dixémoslles: imos facer o mesmo
08:21
but this time there's no director. Instead you've got to
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pero desta volta sen director.
08:24
ignore objects with the dark gray background.
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Esta vez teñen que ignorar
os obxectos co fondo gris.
08:27
You'll see that this is exactly the same condition, only
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Fíxense que é exactamente o mesmo,
08:30
in the no-director condition they just have to remember
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só que agora teñen que acordarse
08:33
to apply this somewhat arbitrary rule, whereas
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de aplicar esta regra un tanto arbitraria,
08:36
in the director condition, they have to remember
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mentres que antes tiñan que recordar
08:38
to take into account the director's perspective
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ter en conta a perspectiva do director
08:41
in order to guide their ongoing behavior.
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para guiar a súa resposta.
08:45
Okay, so if I just show you the percentage errors
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Voulles mostrar a porcentaxe de erros
no estudo de desenvolvemento que fixemos,
08:48
in a large developmental study we did,
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08:51
this is in a study ranging from age seven to adulthood,
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que abarcaba dos 7 anos á idade adulta,
e van ver a porcentaxe de erros
08:54
and what you're going to see is the percentage errors
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08:55
in the adult group in both conditions,
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dos adultos en ambas as dúas condicións,
08:57
so the gray is the director condition, and you see
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en gris a do director, e verán que
09:01
that our intelligent adults are making errors about 50 percent
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os adultos intelixentes
cometen erros un 50% das veces
09:03
of the time, whereas they make far fewer errors
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e que cometen menos erros
09:06
when there's no director present, when they just have
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cando o director non está presente,
09:08
to remember that rule of ignoring the gray background.
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cando teñen que recordar
a regra de ignorar o fondo gris.
09:11
Developmentally, these two conditions develop
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Evolutivamente, estas dúas condicións
09:14
in exactly the same way. Between late childhood
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desenvólvense igual. Hai unha mellora
09:17
and mid-adolescence, there's an improvement,
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entre a infancia e a adolescencia.
09:19
in other words a reduction of errors, in both of these trials,
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Noutras palabras, hai unha redución dos
erros nas dúas condicións.
09:22
in both of these conditions.
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1120
09:23
But it's when you compare the last two groups,
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Pero é cando comparamos
os dous últimos grupos,
09:26
the mid-adolescent group and the adult group
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adolescentes e adultos,
09:28
where things get really interesting, because there, there is
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cando as cousas se poñen interesantes,
09:31
no continued improvement in the no-director condition.
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porque aí non continúa a mellora
na condición sen director.
09:34
In other words, everything you need to do in order to
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Noutras palabras, o necesario
09:37
remember the rule and apply it seems to be fully developed
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para recordar e aplicar a regra
09:39
by mid-adolescence, whereas in contrast,
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xa está desenvolto na adolescencia;
mentres que, se observan
as dúas últimas barras grises,
09:42
if you look at the last two gray bars, there's still
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2397
09:44
a significant improvement in the director condition
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verán que aínda hai
unha mellora significativa
na condición director entre
a adolescencia e a idade adulta.
09:47
between mid-adolescence and adulthood, and what
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2441
09:50
this means is that the ability to take into account someone
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Isto significa que a
capacidade para ter en conta
09:53
else's perspective in order to guide ongoing behavior,
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577864
3285
a perspectiva dos outros
para guiar a nosa conduta,
algo que temos que facer
todos os días a todas horas,
09:57
which is something, by the way, that we do in everyday life all
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2259
09:59
the time, is still developing in mid-to-late adolescence.
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está aínda desenvolvéndose
na adolescencia.
Ou sexa que se teñen un fillo adolescente
10:03
So if you have a teenage son or a daughter and you
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588014
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e algunhas veces pensan que ten problemas
para poñerse no lugar dos outros,
10:06
sometimes think they have problems taking other people's
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2409
10:08
perspectives, you're right. They do. And this is why.
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3756
están no certo. Téñenos.
E este é o motivo.
10:12
So we sometimes laugh about teenagers.
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Ás veces rímonos dos adolescentes.
10:16
They're parodied, sometimes even demonized in the media
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Mesmo os medios
10:19
for their kind of typical teenage behavior. They take risks,
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critican as súas condutas típicas.
10:23
they're sometimes moody, they're very self-conscious.
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Son arriscados, malhumorados,
moi vergonzosos.
10:26
I have a really nice anecdote from a friend of mine
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Teño unha anécdota moi divertida dun amigo
10:28
who said that the thing he noticed most
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2487
que contaba que o cambio máis patente
das súas fillas adolescentes na puberdade
10:31
about his teenage daughters before and after puberty
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2981
foi o grao de vergoña diante del. Dicía:
10:34
was their level of embarrassment in front of him.
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"Antes da puberdade, se as miñas fillas
10:36
So, he said, "Before puberty, if my two daughters
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estaban a amolarme nunha tenda, dicíalles
10:39
were messing around in a shop, I'd say, 'Hey,
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2254
'veña, parade e cántovos
a vosa canción favorita'
10:41
stop messing around and I'll sing your favorite song,'
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e paraban ao momento
e cantáballes a canción".
10:43
and instantly they'd stop messing around and he'd sing
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1901
10:44
their favorite song. After puberty, that became the threat.
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Despois da puberdade,
iso tornouse nunha ameaza.
10:48
(Laughter)
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(Risas)
10:50
The very notion of their dad singing in public
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A simple idea do seu pai
cantando en público
10:53
was enough to make them behave.
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era suficiente para facer
que se comportaran.
10:56
So people often ask,
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A miúdo a xente pregunta:
10:57
"Well, is adolescence a kind of recent phenomenon?
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"A adolescencia é cousa de agora?
11:00
Is it something we've invented recently in the West?"
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2122
Algo inventado en Occidente?"
11:02
And actually, the answer is probably not. There are lots
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Francamente, creo que a resposta é non.
11:04
of descriptions of adolescence in history that sound
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Ao longo da historia hai descricións
da adolescencia
11:08
very similar to the descriptions we use today.
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moi parecidas ás que usamos hoxe en día.
11:10
So there's a famous quote by Shakespeare from "The Winter's Tale"
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4233
Nunha famosa cita de
"Conto de Inverno", Shakespeare
11:14
where he describes adolescence as follows:
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2775
describe así a adolescencia:
11:17
"I would there were no age between ten and
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2846
"Quixera que non mediara tempo
entre os 10 e os 23 anos,
11:20
three-and-twenty, or that youth would sleep out the rest;
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ou que a xuventude pasara
durmindo tranquilamente;
11:23
for there is nothing in the between but getting wenches
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2091
porque non hai nada no ínterim salvo
11:25
with child, wronging the ancientry, stealing, fighting." (Laughter)
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preñar mozas, aldraxar anciáns,
roubar, loitar". (Risas)
11:31
He then goes on to say, "Having said that, would any
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4534
E continúa dicindo: "Dito isto, quen senón
11:36
but these boiled brains of nineteen and two-and-twenty
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esas cabezas loucas de 19 e 22 anos
11:39
hunt in this weather?" (Laughter)
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2498
sairía cazar con este tempo?" (Risas)
11:42
So almost 400 years ago, Shakespeare was portraying
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Ou sexa que hai 400 anos, Shakespeare
11:44
adolescents in a very similar light to the light that we
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2724
retratou aos adolescentes da mesma maneira
11:47
portray them in today, but today we try to understand
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que se fai hoxe, pero aínda estamos
11:51
their behavior in terms of the underlying changes
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3087
a tentar comprender a súa conduta
en termos dos cambios
cerebrais subxacentes.
11:54
that are going on in their brain.
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1938
11:56
So for example, take risk-taking. We know that adolescents
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700285
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Por exemplo, as condutas de risco.
11:59
have a tendency to take risks. They do.
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2325
Sabemos da súa tendencia
a arriscarse. Fano.
12:02
They take more risks than children or adults,
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2632
Corren máis riscos que
os nenos ou os adultos,
12:04
and they are particularly prone to taking risks
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e son particularmente proclives
12:07
when they're with their friends. There's an important drive
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2968
a asumir riscos cando están cos amigos.
12:10
to become independent from one's parents
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Hai un forte pulo para
independizarse dos pais
12:12
and to impress one's friends in adolescence.
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2824
e impresionar aos amigos na adolescencia.
12:15
But now we try to understand that in terms of
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Agora tratamos de comprendelo en termos
12:18
the development of a part of their brain called the limbic system,
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do desenvolvemento
dunha parte do cerebro,
12:21
so I'm going to show you the limbic system in red
255
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o sistema límbico. Poden velo en vermello
na diapositiva detrás de min
e neste cerebro.
12:23
in the slide behind me, and also on this brain.
256
727723
1865
12:25
So the limbic system is right deep inside the brain,
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O sistema límbico está na profundidade
12:28
and it's involved in things like emotion processing
258
732697
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do cerebro e está implicado
no procesamento das emocións
12:32
and reward processing. It gives you the rewarding feeling
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3150
e da recompensa. Dános esa sensación
12:35
out of doing fun things, including taking risks.
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3296
gratificante do divertido, do risco.
12:38
It gives you the kick out of taking risks.
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2365
Dáche ese subidón ao correr un risco.
12:41
And this region, the regions within the limbic system,
262
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Sabemos que esta
rexión do sistema límbico
12:44
have been found to be hypersensitive to the rewarding
263
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3419
é hipersensible á sensación gratificante
12:47
feeling of risk-taking in adolescents compared with adults,
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3769
de arriscarse nos adolescentes
fronte aos adultos,
12:51
and at the very same time, the prefrontal cortex,
265
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e ao mesmo tempo, o córtex prefrontal,
12:55
which you can see in blue in the slide here,
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en azul na diapositiva, que nos impide
12:57
which stops us taking excessive risks,
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correr riscos excesivos, está aínda
13:00
is still very much in development in adolescents.
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3398
en desenvolvemento na adolescencia.
13:03
So brain research has shown that the adolescent brain
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3667
Así que vemos que o cerebro adolescente
13:07
undergoes really quite profound development,
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3342
experimenta un gran desenvolvemento,
13:10
and this has implications for education, for rehabilitation,
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3956
e isto ten implicacións para
a educación, a rehabilitación
13:14
and intervention. The environment, including teaching,
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e a intervención.
O ambiente, escola incluída,
13:18
can and does shape the developing adolescent brain,
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3409
pode e dá forma ao cerebro adolescente.
13:22
and yet it's only relatively recently that we have been
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Con todo, a ensinanza obrigatoria
durante a adolescencia
13:24
routinely educating teenagers in the West.
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2505
é relativamente recente en Occidente.
13:27
All four of my grandparents, for example, left school
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3753
Os meus catro avós, por exemplo,
13:31
in their early adolescence. They had no choice.
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3834
deixaron a escola moi novos.
Non tiñan elección.
13:34
And that's still the case for many, many teenagers
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E isto segue sendo así
para moitos adolescentes
13:37
around the world today. Forty percent of teenagers
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3167
de todo o mundo. O 40% deles
13:40
don't have access to secondary school education.
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4222
non teñen acceso á ensinanza secundaria.
13:45
And yet, this is a period of life where the brain is
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2639
Porén, este é un período da vida
13:47
particularly adaptable and malleable.
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2847
no que o cerebro é particularmente
adaptable e maleable.
13:50
It's a fantastic opportunity for learning and creativity.
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É unha oportunidade fantástica
para a aprendizaxe e a creatividade.
13:54
So what's sometimes seen as the problem
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Ou sexa que o que ás veces se ve como
13:56
with adolescents — heightened risk-taking, poor impulse
285
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o problema da adolescencia
--condutas de risco,
13:59
control, self-consciousness — shouldn't be stigmatized.
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escaso control de impulsos, vergoña--
non debería estigmatizarse.
14:02
It actually reflects changes in the brain that provide
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Reflicte cambios cerebrais
que proporcionan
14:05
an excellent opportunity for education
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unha grande oportunidade para a educación
14:08
and social development. Thank you. (Applause)
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e o desenvolvemento social. Grazas.
14:13
(Applause)
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(Aplausos)
Translated by Montse Corral
Reviewed by Servizo de Normalización Lingüística

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ABOUT THE SPEAKER
Sarah-Jayne Blakemore - Cognitive Neuroscientist
Sarah-Jayne Blakemore studies the social brain -- the network of brain regions involved in understanding other people -- and how it develops in adolescents.

Why you should listen

Remember being a teenager? Rocked internally with hormones, outwardly with social pressures, you sometimes wondered what was going on in your head. So does Sarah-Jayne Blakemore. And what she and others in her field are finding is: The adolescent brain really is different.

New brain imaging research and clever experiments are revealing how the cortex develops -- the executive part of the brain that handles things like planning, self-awareness, analysis of consequences and behavioral choices. It turns out that these regions develop more slowly during adolescence, and in fascinating ways that relate to risk-taking, peer pressure and learning.

Which leads to a bigger question: How can we better target education to speak to teenagers' growing, changing brains?

More profile about the speaker
Sarah-Jayne Blakemore | Speaker | TED.com
THE ORIGINAL VIDEO ON TED.COM