So you’re in line at the grocery store,
and there’s a parent
holding a baby right in front of you.
You’re minding your own business, but whenyou look up,
that baby just won’t stop staring at youlike you’re
the most interesting thing on the planet.
You might feel like you’ve grown a second head,
or like you have chocolate smeared all over your mouth,
but in reality, that baby just likes lookingat your face.
Because there’s a lot to figure out there!
From very early in life,
babies seem to like looking at faces,
or even just configurations of shapes thatlook like faces.
They also prefer faces they recognize to onesthey don’t,
but they’ll sometimes spend a little moretime looking at strangers
because they’re new or different.
Faces are important to babies because they’rebasically
completely helpless and have to rely on theircaregivers to survive.
They need to be able to
find and communicate with the people
who feed them and change their diapers,
and knowing what they look like is an important part of that.
Even if said communication just involves screaming at the top
of their lungs for a while.
Babies are also busy taking in huge amountsof information
to help them understand the world, and faces can teach them a lot.
From our expressions to how our mouths formwords,
a lot of our communication as humans happensthrough our faces.
In those first few months of life,
babies are not only beginning to learn
how to recognize their parents or grandparents,
but also about all the emotions conveyed byfacial expressions.
There’s a lot to learn!
So when a baby is staring
at you in the grocery store,
her little brain is probably trying to figure
if she knows you
and what categories your face fits into,
like if you’re happy or sad. Now,
babies might be born
ready to learn from the world around them,
but there’s still some question about
whether looking at faces is an innate characteristic—
one you’re born with—or if it’s influencedby experience. And,
like with a lot
of the age-old, nature versus nurture debate,
it’s a little bit of both.
On the nature side, there’s some evidence that,
within hours to days of being born,
babies can copy facial expressions they see,
like if you stick out your tongue at them.
Not all studies agree with those results,
but it’s possible that there’s
an innate ability for finding and mimickingexpressions.
Other research has found that within hoursof birth,
babies can discriminate between their mother’sface and a stranger’s,
which might mean their brain is ready to recognize faces without much information. So,
some evidence suggests that babies maybe predisposed to
look for information from faces right whenthey’re born.
But other studies have shown
that it takes experience to get really good at it.
Either way, all the time
babies and their caregivers spend looking at each other
causes rapid improvement in babies’ abilitiesto process and recognize faces.
Starting around 3 months old,
they even begin to group different kinds of faces—
like human versus animals and kids versusadults.
One especially cool study had babies and adults look
at a series of different monkey faces,
and also at a bunch of different adult humanfaces.
They found that 6-month-old babies are actuallybetter at
differentiating between monkey faces thanadults are!
But when they’re about 9 months old, thatability goes away
because of what’s called perceptual narrowing,
where their perception starts to change basedon their experience. Basically,
the baby learns
that paying attention to the differences in human faces
is way more important for its life
than the differences in monkey faces,
so it should focus more on humans than monkeys.
As the brain develops over time, the pathwaysused to recognize
human faces get more efficient, and the ones for monkeys get pruned away.
But when researchers expose babies to lotsof monkey faces
between when they’re 6 and 9 months old,
they effectively teach their brains
that monkeys are important to pay attention to,
so they keep that ability for a lot longer.
Even though babies are born with some skills,
experience helps tell them what parts
of the world they should pay attention to,
and that shapes how their brain’s perceptionand recognition systems develop. So,
it’s a little bit
of nature and a little bit of nurture
that goes into that cute, big-eyed baby staringat you.
And yeah, in that moment,
your face might just be the most interesting thing on the planet.
But don’t rule
out the possibility that you might have a little chocolate on your face, too.
Thanks for watching this episode of SciShow Psych,
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