One of Harry Houdini’s better-known quotations is: “My brain is the key that sets my mind free.”

The famed magician, and all magicians for that matter, know more than most about how the brain works—even if not on strictly scientific terms. For that, we have neuroscientists Stephen L. Macknik and Susana Martinez-Conde, authors of a book on “neuromagic” called Sleights of Mind. They’re interested in the ways magicians manipulate the minds of an audience in order to successfully maneuver tricks.

In the video from Scientific American above, you can hear Macknik and Martinez-Conde discuss their findings—and get totally mesmerized by a classic cup and balls trick performed by magician Joshua Jay. Most table (or “close up”) magic tricks are about misdirection, when the performer does multiple things at once in order to divert the audience’s attention in a purposeful way. Our brains can really only follow one thing at a time (as Macknik says, “there is no such thing as multitasking with attention”) so it can be easy for a magician to get the audience to focus on something unimportant so they block out the sleight of hand happening nearby.

The most amazing—or most frustrating—thing about this neuro-tendency is that it’s sort of impossible to defy. Even when we know how magic works, it doesn’t change the way the brain functions. The magician can still stay ahead of the audience, and manage to trick magic-hunting eyes and minds. Not believing doesn’t change what you’re seeing.