The Social Brain: Stephanie White at TEDxUCLA


Translator: Naoko Fujii
Reviewer: Denise RQ I’m a scientist
that cares about the brain. What I’m wondering right now is whether what’s going on
in your brain would be the same if instead of looking at me here, you were watching me
on the video screen up there. I think the answer is no. And this issue, this idea, of the impact
of live versus virtual social interactions has huge implications
for how we educate ourselves, for our mental health,
and even for our evolution as a species. Let me tell you why I think that. Scientists know that American babies
can learn to distinguish the sounds that are important for Mandarin Chinese if and only if they are tutored
by live Mandarin speakers, not when they are shown
the video of that same person. At the other end of the life span,
the best thing you and I can do to stave off dementia
as we age is to be bilingual. And this is the best protector,
better than any pharmaceutical currently on the market
in delaying Alzheimer’s; in some studies, by as much as five years. So language is very powerful. And in a sense, it offers
a passport into our brains. But as a neuroscientist,
there is a problem; language is uniquely human. And this makes very difficult
to get at the nuts and bolts of how the brain gives rise to language. Fortunately, sub-components
of language exist in other species, and one of these is vocal learning. This is our ability to modify
the sounds that we make, like we do when we are learning to speak. Now, among primates,
humans are the only species capable of greatly modifying
the sounds that they make. Here in So Cal, another one
of vocal learning friends are dolphins. But again, neither humans
or dolphins are very amenable to control physiological experimentation. So I study songbirds
who have this capacity in spades, and much more so than a typical lab rat. Now, although vocal learning
is uniquely human, when it goes awry, it can have
profound consequences for our sense of well-being
and social integration and that’s evident in this video here, of a girl describing how she feels about
her speech and language disorder. (Video) Well, I think it was terrible because my friends
do not understand me a bit. Stephanie White:
So she thinks it’s terrible. She’s had very intensive speech therapy. She’s a member of a remarkable family
known as the KE family, half of whom suffer from
this severe speech and language disorder. And in 2001, the cause of their deficits, a mutation in a molecule
known as FoxP2, was found. Now, FoxP2 is a master control molecule, meaning that it governs the expression
of a lot of other molecules, like a conductor directing
diverse musicians to produce a beautiful concert. So FoxP2 really is unique
in its direct link to language. A mutation alters its function,
alters the way the brain develops, and alters the way we speak. Before you think that my story
is over, think about this: FoxP2 isn’t in just our brains,
it’s in almost all of our body organs, it’s in our heart,
our liver, our kidneys. So why is it that a mutation of FoxP2
just causes problems for language? And FoxP2 is in other organisms
that we don’t think of as vocal learners, like fruit flies who don’t sing or speak. So how can FoxP2 have
this direct profound effect on language? I think part of the answer is
that FoxP2 cares about social contexts. Its levels change in the brain
when one vocalizes. But the change depends on
who is around, who is in the social scene. And when one changes, so do to levels
of all the other genes that it directs, parts of its molecular network, much like our social networks
that we are familiar with. So I think it’s this social sensitivity
and a suite of genes that FoxP2 is part of
that gives its direct effect on language. Let me tell you how we made
these discoveries using a songbird. Birds’ song can really tell us
a lot about human speech because, like humans,
songbirds are vocal learners. Like humans, they learn
through social interactions. Like humans, they learn best
early in development, using similar brain structures
and similar genes. So for example, early in life, both songbirds and humans
enter into a vocal learning phase where they’re not vocalizing new sounds, they are just listening to
the sounds of those around them. And then later on, they start
making their own new sounds which in humans just call babbling. And both song and speech
depend upon being able to hear. Deafness causes both to degrade. Now, songbirds maintain
the quality of their vocalizations by engaging in cycles
of practice and performance. Performance is when a male songbird
sings to a female song bird in order to court her, and practice is
when he sings his song alone. Those two songs look very much the same as I’m showing you here
on a sonogram with time versus frequency, and they sound the same to us, but a female bird can tell the difference. So we decided to look at FoxP2
in the brain of an adult male songbird. Here I’m showing you
snapshots of two bird brains. (Laughter) This bird didn’t sing. This bird did. The levels of FoxP2 are
shown by how dark it is so there is lots of FoxP2 here,
and not so much here. We quantify this in two different ways,
and came up with similar results. But now look what happens when the bird actually
practices his song by himself. Something very different happens. FoxP2 level is dropped dramatically,
and precisely in the part of the brain that’s responsible
for these vocalizations. So though the song looks
the same to us, and sounds the same, FoxP2 levels and these two conditions
are very different because FoxP2 cares about social contexts. And when FoxP2 levels change, so did the levels of all
the other molecules that it directs. So songbirds really tell us that our social interactions
can affect our brains. And currently, our real interactions are
more powerful than the virtual ones. Just like human babies,
songbirds don’t learn well from tape. And I have to make a guess,
I would say that during an interaction, not only the person you are interacting
with is paying attention to you but they are paying attention to
whether you’re paying attention to them. I think it’s this engagement
that requires this focus that’s the key to our mental health,
our educational systems, and even our evolution as a species. Thank you. (Applause)

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