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 has 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 are 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,

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 seat belt, 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.

(Gasps)

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's 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.

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.

The way that we see emotions in others are deeply rooted in predictions.

So to us, it feels like we just look at someone's face,

and we just read the emotion that's there in their facial expressions

the way that we would read words on a page.

But actually, under the hood, your brain is predicting.

It's using past experience based on similar situations

to try to make meaning.

This time, you're not making meaning of blobs,

you're making meaning of facial movements

like the curl of a lip or the raise of an eyebrow.

And that stone-faced stare?

That might be someone who is a remorseless killer,

but a stone-faced stare might also mean

that someone is stoically accepting defeat,

which is in fact what Chechen culture prescribes for someone

in Dzhokhar Tsarnaev's situation.

So the lesson here

is that emotions that you seem to detect in other people

actually come in part from what's inside your own head.

And this is true in the courtroom,

but it's also true in the classroom,

in the bedroom,

and in the boardroom.

And so here's my concern:

tech companies which shall remain nameless ...

well, maybe not.

You know, Google, Facebook --

(Laughter)

are spending millions of research dollars to build emotion-detection systems,

and they are fundamentally asking the wrong question,

because they're trying to detect emotions in the face and the body,

but emotions aren't in your face and body.

Physical movements have no intrinsic emotional meaning.

We have to make them meaningful.

A human or something else has to connect them to the context,

and that makes them meaningful.

That's how we know that a smile might mean sadness

and a cry might mean happiness,

and a stoic, still face might mean

that you are angrily plotting the demise of your enemy.

Now, if I haven't already gone out on a limb,

I'll just edge out on that limb a little further and tell you

that the way that you experience your own emotion

is exactly the same process.

Your brain is basically making predictions, guesses,

that it's constructing in the moment

with billions of neurons working together.

Now your brain does come prewired to make some feelings,

simple feelings that come from the physiology of your body.

So when you're born,

you can make feelings like calmness and agitation,

excitement, comfort, discomfort.

But these simple feelings are not emotions.

They're actually with you every waking moment of your life.

They are simple summaries of what's going on inside your body,

kind of like a barometer.

But they have very little detail,

and you need that detail to know what to do next.

What do you about these feelings?

And so how does your brain give you that detail?

Well, that's what predictions are.

Predictions link the sensations in your body

that give you these simple feelings

with what's going on around you in the world

so that you know what to do.

And sometimes,

those constructions are emotions.

So for example, if you were to walk into a bakery,

your brain might predict that you will encounter

the delicious aroma of freshly baked chocolate chip cookies.

I know my brain would predict

the delicious aroma of freshly baked chocolate cookies.

And our brains might cause our stomachs to churn a little bit,

to prepare for eating those cookies.

And if we are correct,

if in fact some cookies have just come out of the oven,

then our brains will have constructed hunger,

and we are prepared to munch down those cookies

and digest them in a very efficient way,

meaning that we can eat a lot of them,

which would be a really good thing.

You guys are not laughing enough. I'm totally serious.

(Laughter)

But here's the thing.

That churning stomach,

if it occurs in a different situation,

it can have a completely different meaning.

So if your brain were to predict a churning stomach

in, say, a hospital room while you're waiting for test results,

then your brain will be constructing dread

or worry or anxiety,

and it might cause you to, maybe,

wring your hands

or take a deep breath or even cry.

Right? Same physical sensation, same churning stomach,

different experience.

And so the lesson here

is that emotions which seem to happen to you

are actually made by you.

You are not at the mercy of mythical emotion circuits

which are buried deep inside some ancient part of your brain.

You have more control over your emotions

than you think you do.

I don't mean that you can just snap your fingers

and change how you feel the way that you would change your clothes,

but your brain is wired

so that if you change the ingredients that your brain uses to make emotion,

then you can transform your emotional life.

So if you change those ingredients today,

you're basically teaching your brain how to predict differently tomorrow,

and this is what I call being the architect of your experience.

So here's an example.

All of us have had a nervous feeling before a test, right?

But some people experience crippling anxiety before a test.

They have test anxiety.

Based on past experiences of taking tests,

their brains predict a hammering heartbeat,

sweaty hands,

so much so that they are unable to actually take the test.

They don't perform well,

and sometimes they not only fail courses but they actually might fail college.

But here's the thing:

a hammering heartbeat is not necessarily anxiety.

It could be that your body is preparing to do battle

and ace that test ...

or, you know, give a talk

in front of hundreds of people on a stage where you're being filmed.

(Laughter)

I'm serious.

(Laughter)

And research shows that when students learn

to make this kind of energized determination

instead of anxiety,

they perform better on tests.

And that determination seeds their brain to predict differently in the future

so that they can get their butterflies flying in formation.

And if they do that often enough,

they not only can pass a test

but it will be easier for them to pass their courses,

and they might even finish college,

which has a huge impact on their future earning potential.

So I call this emotional intelligence in action.

Now you can cultivate this emotional intelligence yourself

and use it in your everyday life.

So just, you know,

imagine waking up in the morning.

I'm sure you've had this experience. I know I have.

You wake up and as you're emerging into consciousness,

you feel this horrible dread,

you know, this real wretchedness,

and immediately, your mind starts to race.

You start to think about all the crap that you have to do at work

and