You're walking through a park when out of nowhere, the man in
front of you gets smacked by an errant Frisbee. Automatically,
you recoil in sympathy. Or you're watching a race, and you feel
your own heart racing with excitement as the runners vie to
cross the finish line first. Or you see a woman sniff some
unfamiliar food and wrinkle her nose in disgust. Suddenly, your
own stomach turns at the thought of the meal. For years, such
experiences have puzzled psychologists, neuroscientists and
philosophers, who've wondered why we react at such a gut level
to other people's actions. How do we understand, so immediately
and instinctively, their thoughts, feelings and intentions? Now,
some researchers believe that a recent discovery called mirror
neurons might provide a neuroscience-based answer to those
questions. Mirror neurons are a type of brain cell that respond
equally when we perform an action and when we witness someone
else perform the same action. They were first discovered in the
early 1990s, when a team o