Wired to Weep, Wired to Rejoice

In 1992, neuroscientist Giacomo Rizzolatti and his team at the University of Parma made a startling discovery. While studying motor neurons in macaque monkeys, they noticed something unexpected: when one of their researchers reached for food, certain neurons in a monkey's brain fired — even though the monkey hadn't moved at all. It was simply watching. They named these cells mirror neurons, and subsequent research suggests that humans have an even more sophisticated version of the same system.…