that you can say about someone is "they choked."

And boy, do I know that feeling.

Growing up, I was an avid athlete.

My main sport was soccer, and I was a goalkeeper,

which is both the best and the worst position on the field.

You see, when you're a goalie, you get this special uniform,

you get all the glory for a great shot saved,

but you also get the grief when you land a shot in the goal.

When you're a goalie,

all eyes are on you,

and with that comes the pressure.

I distinctly remember one game in high school.

I was playing for the California state team

which is part of the Olympic Development Program.

I was having a great game ...

until I realized that the national coach was standing right behind me.

That's when everything changed.

In a matter of seconds,

I went from playing at the top to the bottom of my ability.

Just knowing that I was being evaluated changed my performance

and forever how I thought about the mental aspect of how we perform.

All of a sudden the ball seemed to go in slow motion,

and I was fixated on my every move.

The next shot that came I bobbled,

but thankfully it didn't land in the goal.

The shot after that,

I wasn't so lucky:

I tipped it right into the net.

My team lost;

the national coach walked away.

I choked under the pressure of those evaluative eyes on me.

Just about everyone does it from time to time --

there are so many opportunities,

whether it's taking a test,

giving a talk,

pitching to a client

or that special form of torture I like to call the job interview.

(Laughter)

But the question is why.

Why do we sometimes fail to perform up to our potential under pressure?

It's especially bewildering in the case of athletes

who spend so much time physically honing their craft.

But what about their minds?

Not as much.

This is true off the playing field as well.

Whether we're taking a test of giving a talk,

it's easy to feel like we're ready --

at the top of our game --

and then perform at our worst when it matters most.

It turns out that rarely do we practice

under the types of conditions we're actually going to perform under,

and as a result,

when all eyes are on us,

we sometimes flub our performance.

Of course, the question is, why is this the case?

And my experience on the playing field --

and in other important facets of my life --

really pushed me into the field of cognitive science.

I wanted to know how we could reach our limitless potential.

I wanted to understand how we could use our knowledge

of the mind and the brain

to come up with psychological tools that would help us perform at our best.

So why does it happen?

Why do we sometimes fail to perform up to what we're capable of

when the pressure is on?

It may not be so surprising to hear that in stressful situations, we worry.

We worry about the situation,

the consequences,

what others will think of us.

But what is surprising is that we often get in our own way

precisely because our worries prompt us to concentrate too much.

That's right --

we pay too much attention to what we're doing.

When we're concerned about performing our best,

we often try and control aspects of what we're doing

that are best left on autopilot,

outside conscious awareness,

and as a result,

we mess up.

Think about a situation where you're shuffling down the stairs.

What would happen if I asked you

to think about what you're doing with your knee

while you're doing that?

There's a good chance you'd fall on your face.

We as humans only have the ability to pay attention to so much at once,

which is why, by the way,

it's not a good idea to drive and talk on the cell phone.

And under pressure,

when we're concerned about performing at our best,

we can try and control aspects of what we're doing

that should be left outside conscious control.

The end result is that we mess up.

My research team and I have studied this phenomenon of overattention,

and we call it paralysis by analysis.

In one study, we asked college soccer players to dribble a soccer ball

and to pay attention to an aspect of their performance

that they would not otherwise attend to.

We asked them to pay attention

to what side of the foot was contacting the ball.

We showed that performance was slower and more error-prone

when we drew their attention to the step-by-step details

of what they were doing.

When the pressure is on,

we're often concerned with performing at our best,

and as a result we try and control what we're doing

to force the best performance.

The end result is that we actually screw up.

In basketball,

the term "unconscious" is used to describe a shooter who can't miss.

And San Antonio Spurs star Tim Duncan has said,

"When you have to stop and think, that's when you mess up."

In dance, the great choreographer, George Balanchine,

used to urge his dancers,

"Don't think, just do."

When the pressure's on,

when we want to put our best foot forward,

somewhat ironically,

we often try and control what we're doing in a way that leads to worse performance.

So what do we do?

Knowing that we have this overactive attention,

how do we ensure that we perform at our best?

A lot of it comes down to the prefrontal cortex,

that front part of our brain that sits over our eyes

and usually helps us focus in positive ways.

It often gets hooked on the wrong things.

So how do we unhook it?

Something as simple as singing a song,

or paying attention to one's pinky toe,

as pro golfer Jack Nicklaus was rumored to do,

can help us take our mind off those pesky details.

It's also true that practicing under conditions

that we're going to perform under --

closing the gap between training and competition

can help us get used to that feeling of all eyes on us.

This is true off the playing field as well.

Whether it's getting ready for an exam

or preparing for a big talk --

one that might have a little pressure associated with it --

(Laughter)

getting used to the types of situations you're going to perform under

really matters.

When you're taking a test, close the book,

practice retrieving the answer from memory under timed situations,

and when you're giving a talk,

practice in front of others.

And if you can't find anyone who will listen,

practice in front of a video camera or even a mirror.

The ability to get used to what it will feel like can make the difference

in whether we choke or thrive.

We've also figured out some ways to get rid of those pesky worries

and self-doubts that tend to creep up in the stressful situations.

Researchers have shown that simply jotting down your thoughts and worries

before a stressful event

can help to download them from mind --

make them less likely to pop up in the moment.

It's kind of like when you wake up in the middle of the night

and you're really worried about what you have to do the next day,

you're trying to think about everything you have to accomplish,

and you write it down and then you can go back to sleep.

Journaling, or getting those thoughts down on paper,

makes it less likely they'll pop up and distract you in the moment.

The end result is that you can perform your best when it matters most.

So up until now,

I've talked about what happens when we put limits on ourselves

and some tips we can use to help perform up to our potential.

But it's important to remember

that it's not just our own individual being

that can put limits and that can perform poorly;

our environment has an effect on whether we choke or thrive.

Our parents, our teachers, our coaches, our bosses all influence

whether or not we can put our best foot forward when it matters most.

Take math as an example.

That's right, I said it:

math.

Lots of people profess to choke or are anxious about doing math,

whether it's taking a test or even calculating the tip on a dinner bill

as our smart friends look on.

And it's quite socially acceptable

to talk about choking or performing poorly in math.

You don't hear highly educated people walking around talking about the fact

or bragging about the fact that they're not good readers,

but you hear people all the time bragging about how they're not math people.

And unfortunately,

in the US, this tends to be more so among girls and women

than boys and men.

My research team and I have tried to understand

where this fear of math comes from,

and we've actually peered inside the brains

using functional magnetic resonance imaging,

of people who are worried about math.

We've shown that math phobia correlates with a concrete visceral sensation

such as pain,

of which we have every right to feel anxious.

In fact, when people who are worried about math

are just getting ready to take a math test --

they're not even taking it, they're just getting ready --

areas of the brain known the be involved in our neural pain response are active.

When we say math is painful,

there's some truth to it for some people.

But where does this math anxiety come from?

It turns out that math anxiety is contagious.

When adults are worried about math,

the children around them start worrying, too.

As young as first grade,

when kids are in classrooms

with teachers who are anxious about their own math ability,

these kids learn less across the school year.

And it turns out that this is more prevalent in girls than boys.

At this young age,

kids tend to mimic same-sex adults,

and at least in the US,

over 90 percent of our elementary school teachers are women.

Of course, it's not just what happens in the classroom.

Social media plays a big role here, too.

It wasn't so long ago

that you could purchase a Teen Talk Barbie

that when the cord was pulled,

it would say things like,

"Will we ever have enough clothes?"

and "Math class is tough."

And just a few years ago,

major retailers were marketing T-shirts at our young girls

that read things like, "I'm too pretty to do math,"

or, "I'm too pretty to do my homework so my brother does it for me."

And let's not forget about the parents.

Oh, the parents.

It turns out that when parents are worried about their own math ability

and they help their kids a lot with math homework,

their kids learn less math across the school year.

As one parent put it,

"I judge my first grader's math homework

by whether it's a one-glass assignment or a three-glass night."

(Laughter)

When adults are anxious about their own math ability,

it rubs off on their kids

and it affects whether they choke or thrive.

But just as we can put limits on others,

we can take them off.

My research team and I have shown

that when we help parents do fun math activities with their kids --

rather than, say, just doing bedtime stories or bedtime reading,

they do bedtime math,

which are fun story problems to do with your kids at night,

not only do children's attitudes about math improve,

but their math performance across the school year improves as well.

Our environment matters.

From the classroom to parents to media,

and it can really make a difference in terms of whether we choke or thrive.

Fast-forward from my high school soccer game

to my freshman year in college.

I was in the chemistry sequence for science majors,