You aren't at the mercy of your emotions -- your brain creates them

My research lab sits about a mile

from where several bombs exploded

during the Boston Marathon in 2013.

The surviving bomber,
Dzhokhar Tsarnaev of Chechnya,

was tried, convicted,
and sentenced to death.

Now, when a jury has to make the decision

between life in prison
and the death penalty,

they base their decision largely
on whether or not the defendant

feels remorseful for his actions.

Tsarnaev spoke words of apology,

but when jurors looked at his face,

all they saw was a stone-faced stare.

Now, Tsarnaev is guilty,

there's no doubt about that.

He murdered and maimed innocent people,

and I'm not here to debate that.

My heart goes out
to all the people who suffered.

But as a scientist, I have to tell you

that jurors do not
and cannot detect remorse

or any other emotion in anybody ever.

Neither can I, and neither can you,

and that's because emotions
are not what we think they are.

They are not universally
expressed and recognized.

They are not hardwired brain reactions

that are uncontrollable.

We have misunderstood
the nature of emotion

for a very long time,

and understanding what emotions really are
have important consequences for all of us.

I have studied emotions as a scientist
for the past 25 years,

and in my lab, we have probed human faces
by measuring electrical signals

that cause your facial muscles to contract
to make facial expressions.

We have scrutinized
the human body in emotion.

We have analyzed hundreds
of physiology studies

involving thousands of test subjects.

We've scanned hundreds of brains,

and examined every
brain imaging study on emotion

that has been published
in the past 20 years.

And the results of all of this research
is overwhelmingly consistent.

It may feel to you

like your emotions are hardwired

and they just trigger and happen to you,

but they don't.

You might believe that your brain
is prewired with emotion circuits,

you know, that you're born
with emotion circuits, but you're not.

In fact, none of us in this room
have emotion circuits in our brain.

In fact, no brain on this planet
contains emotion circuits.

So what are emotions really?

Well, strap on your seatbelt,

because emotions are guesses.

They are guesses that your brain
constructs in the moment

where billions of brain cells
are working together,

and you have more control
over those guesses

than you might imagine that you do.

Now, if that sounds preposterous to you,
or, you know, kind of crazy,

I'm right there with you, because frankly,
if I hadn't seen the evidence for myself,

decades of evidence for myself,

I am fairly sure that I
wouldn't believe it either.

But the bottom line is that emotions
are not built into your brain at birth.

They are just built.

To see what I mean, have a look at this.

Right now, your brain

is working like crazy.

Your neurons are firing like mad
trying to make meaning out of this

so that you see something
other than black and white blobs.

Your brain is sifting
through a lifetime of experience,

making thousands of guesses
at the same time,

weighing the probabilities,

trying to answer the question,

"What is this most like?"

not "What is it?"

but "What is this most like
in my past experience?"

And this is all happening
in the blink of an eye.

Now if your brain is still struggling
to find a good match

and you still see black and white blobs,

then you are in a state
called "experiential blindness,"

and I am going to cure you
of your blindness.

This is my favorite part.
Are you ready to be cured?

(Cheers)

All right. Here we go.

All right.

So now many of you see a snake,

and why is that?

Because as your brain is sifting
through your past experience,

there is new knowledge there,

the knowledge that came
from the photograph.

And what's really cool is that

that knowledge which you
just acquired moments ago

is changing how you experience
these blobs right now.

So your brain is constructing
the image of a snake

where there is no snake,

and this kind of a hallucination

is what neuroscientists like me
call "predictions."

Predictions are basically
the way your brain works.

It's business as usual for your brain.

Predictions are the basis
of every experience that you have.

They are the basis
of every action that you take.

In fact, predictions are what allow you
to understand the words that I'm speaking

as they come out of my --

Audience: Mouth.
Lisa Feldman Barrett: Mouth. Exactly.

Predictions are primal, right?

They help us to make sense
of the world in a quick and efficient way.

So your brain

does not react to the world.

Using past experience,

your brain predicts and constructs

your experience of the world.