[Campos] Emotion is a nonverbal language.
[woman] Is your tummy ticklish?
[Campos] Emotions reveal the cognition, the understanding of the baby.
And, furthermore,
emotions are the nonverbal communication
of the baby towards the parent, and the parent towards the baby.
Therefore, I thought that emotions
were a royal road— one royal road—
to the study of the baby's development.
[narrator] In this study, babies between 9 and 12 months
are brought into the lab and placed on a large, plexiglass top table.
Half of the table has a checkerboard pattern,
just underneath the surface.
But halfway across is a visual cliff,
which the baby can tell drops off steeply.
The plexiglass top continues, so it's perfectly fine to proceed.
But the baby isn't so sure,
and this is a big drop for a baby just starting to crawl.
She wants to get across to get the toy,
but she's cautious, and looks to the opposite end of the table
where her mother is.
The parent is instructed to smile or make a fear face.
If the mother is posing a fear face, the baby typically does not cross
this stair step downward,
this modified visual cliff or visual step.
On the other hand, if the mother poses a smile,
or somehow poses a nonverbal communication
that is not prohibitive, but encouraging,
the child is much more likely
to cross over to her.
This particular study demonstrates
the role of nonverbal communication
in determining the child's behavior in uncertain context.
A baby will, when they encounter something ambiguous, something uncertain,
will typically look to the significant other—
the mother, the father,
a grandparent, the caregiver—
in order to figure out what to do.
So, by 11-12 months of age, the baby is already doing
what all of us do when something unusual happens.
We look around to figure out how other people are reacting.