The Science of Crooners Turning Girls Into Swooners

ABC News' Neal Karlinsky and Felicia Patinkin report:

Just in the way Michael Jackson used to thrill girls of all ages with his moves and music, teenage girls nowadays lose their minds when they listen to modern-day crooners like One Direction and Usher.

We can now report that it's not their fault. Really.

It turns out when a teenage girl gets a popular song stuck in her head, it really does, quite literally, get stuck in her head. The songs trigger her developing brain to release dopamine, the same neurotransmitter involved in pleasure and addiction.

Dr. Daniel Levitin, a neuroscientist and author of the book "This is Your Brain on Music," says the songs are "similar to the chemicals that are released in our brains when we eat chocolate or eat any food that we like or have sex."

Neuroscience studies how the brain reacts to all kinds of things. Justin Bieber fans have a particularly strong reaction to his catchy melodies. So much so, it may cause them to have some pretty compulsive behavior.

"Top craziest moments are Norway, Norway was nuts. I mean we had a boat chase. I was on a boat and basically we had an escort and there was hundreds of fan boats chasing me behind it. It was crazy," Bieber explained.

This is what might be called "your brain on Bieber."

While most young girls can't tell you why they feel an overwhelming urge to chase a pop star, MRI scans show their brains in the same frenzy as a compulsive gambler on a winning streak.

From Elvis to The Beatles, even Leif Garrett in the 1970s appreciated the madness but never quite understood it.

"It's a phenomenon, it's just very bizarre, but I think it's just the incorporation of a lot of things. And there is that primal, you know, instinct, of attraction," Garrett said.

His teenaged fans are now middle-aged, and they're still nuts for him.

Researchers say that's because musical tastes formed as a teen become part of the brain's hard wiring. Meaning when it comes to "Bieber Fever" and "One Direction Infection" there is no cure.