At first glance, a neuroscientist and a business school might seem an odd fit. But in fact economists have been paying increasing attention to how the brain works.The children’s classic The Polar Express tells the fanciful story of a young boy’s journey to the North Pole on a train filled with chocolate and candy. But when Warner Brothers released a $165 million computer-animated version of the tale, many critics described the film not as a happy Christmas fantasy but as a horror movie. “This season’s biggest holiday extravaganza, ‘The Polar Express,’ should be subtitled ‘The Night of the Living Dead,’ ” groused CNN reviewer Paul Clinton. “ If I were a kid, I’d have nightmares,” wrote Geoff Pevere in the Toronto Star.The problem was that while the film’s characters appeared astonishingly human in many ways, their eyes looked lifeless. Viewers were creeped out.Humans are often delighted by objects with vaguely humanoid characteristics—think Pet Rocks, toy robots, or sock puppets. But there is a point at which an object looks almost human, yet not quite human enough, and the result is disturbing. It’s called the uncanny valley. And for Christine Looser, it’s the starting point for a line of research aimed at discovering how our brains detect life, and how we distinguish the cognizant from the mindless.“What I’m interested in is how and why the brain evolved to pay attention to other people,” says Looser, a fellow at Harvard Business School who sports a PhD in cognitive neuroscience.