This is Hidden Brain. I'm Shankar Vedantam.

In high school, Naomi Rothman was a shy teenager.

That is, until she laced up her cleats and stepped on the field for her travel soccer team.

Surrounded by teammates she loved, Naomi became a completely different person.

We were called the Red Hot Chili Peppers, and it was very meaningful to me. she loved, Naomi became a completely different person.

We were called the Red Hot Chili Peppers, and it was very meaningful to me because I created these really strong friendships, and it gave me a lot of confidence, it gave me a sense

of self-worth and self-esteem, and I really strongly identified with this team.

There was just one catch.

The players on this team predominantly came from the east side of town

and played at Harbor High.

Naomi School, Santa Cruz High,

was on the west side of our hometown of Santa Cruz, California.

And so during our high school season, we had to play against each other, and someone always had to lose.

Harbour and Santa Cruz were always among the top contenders. The rivalry between the schools was intense.

Every game we played against one another was high stakes. And these games were some of the most

emotionally fraught games that I ever played. And the reason was that I loved these players.

I had this deep, genuine affection for the people that I was trying to beat.

The same player she had fought alongside as a member of the Red Hot Chili Peppers

were now trying to crush her when Harbor High faced Santa Cruz.

Her friends had become her frenemies.

Next year, Her friends had become her frenemies. Naomi Rothman never forgot what that early experience felt like.

Today, she's a psychologist who studies what happens to our minds

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