Real Life 'Inception': How To Guide Your Dreams (VIDEO)

The hit film "Inception," starring Leonardo DiCaprio and Ellen Page, has been sitting at the top of the box office for three weeks now. The film centers around the idea of manipulating your dreams. But did you know that, for some people, dream control is a reality?

Turns out, there is a whole body of science around tapping into the power of your dreams. Psychologists sometimes prescribe this type of "lucid dreaming" -- the ability to become conscious mid-dream and thus, control your dream world -- as a form of therapy for people with post-traumatic stress or reoccurring nightmares.

"You can tell yourself at bedtime that you want to dream about a particular topic, that you want to be lucid in your dream," said Deirdre Barrett, Ph.D. a dream researcher at Harvard University and author of "The Committee of Sleep."

Experts say you'll be more likely to be able to have lucid dreams if you sleep 9 or 10 hours a night, as REM cycles get longer and deeper.

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