Issue Date: January 15, 2006

BOOKS

Brain power

A med student plugs in.

By Kathleen Conroy

Shannon Moffett thinks hard about the human brain -- she has since she decided to become a doctor. The Stanford University School of Medicine student, 33, says "almost everything about who we are distills down to the movement of organic molecules and biochemical reactions in our brains. A fascinating concept, and I wanted to learn more about it." The result is her first book, "The Three-Pound Enigma: The Human Brain and the Quest to Unlock Its Mysteries" (Algonquin, $24.95). We spoke with her:

Any truth to the adage that we use less than 10% of our brain power?
Scientists have no idea how much "power" our brains have. There are no units of measurement to describe how hard we're thinking or how much of our brains we're using. I've never heard of any reports of anyone's brain being full-up, though, so we probably don't need to try to conserve brain power!

Where do "big" ideas originate in a brain?
No one knows where in the brain any of our ideas come from. But it's generally agreed that they don't come from any one place but are a product of the interaction of multiple areas.

What do you think is the brain's most amazing characteristic?
Its incredible flexibility, evident when we learn a new skill, such as how to speak an unfamiliar language or how to play the violin. Even after the destruction of half the brain, the other half of the brain is capable of taking over.

Why do our memories change over time?
Your memory may change as you get new information or experiences. That's why memory is so famously unreliable.