This is Hidden Brain, I'm Shankar Vedanta.

If you type in the words left brain versus right brain on YouTube,

it's not long before you'll find yourself in a vortex of weird claims and outlandish hype.

With the left brain imbalance, the overall function of the brain is stunted

so that the oldest part of the brain, the reptile brain, takes over on an instinctual level.

Men, men need formulas, we need systems. That's a left brain by the way for men.

Now the problem is is that most people are either exclusively left brain or right brain.

They're one or the other.

For decades, pop psychology books and plenty of YouTube videos

have made dramatic claims about people who are left brained and people who are right brained.

It got to the point that respectable scientists felt they had to steer clear

of the study of hemispheric differences.

I was told when I got involved in this area, don't touch it, it's toxic, don't even go that.

This week on Hidden Brain, we follow the work of a researcher who went there.

What he's found is much more nuanced and complex than the story on YouTube.

His conclusions though might be even more dramatic.

He argues that differences in the brain and Western society's preference for what one

hemisphere has to offer have had enormous effects on our lives.

Ian McGillcrest is a psychiatrist. He has spent years studying the human brain

through case studies of his patients and a detailed examination of scientific research.

He's found himself fascinated with a question that is intrigued philosophers and scientists for centuries.

Why is the human brain divided in half?

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