(CNN) -- Whether he's peering into the mind of a mass murderer or spinning tales of the afterlife, bestselling author and neuroscientist David Eagleman is wrestling with some of the most profound questions of our existence. What is time? What is consciousness? How does the human brain construct reality?
"I'm very interested in the perceptual machinery by which we view the world," Eagleman says, "and how we make decisions, our beliefs, our actions in the world."
As head of the Laboratory for Perception and Action at Baylor College of Medicine in Houston, Eagleman and his students are pursuing some 50 different projects on the human brain. They study topics from time perception and brain plasticity to synesthesia, a condition characterized by a blending of senses. For research assistant and synesthete Hannah Bosley, synesthesia means that she associates letters and numbers with different colors.
"For example," she says, "the word dog is D-O-G. It's also yellow, clear and green to me."
Eagleman also looks at how the differences in our brains matter on a societal level. "When you see somebody commit a very strange abnormal act, like a school shooting or a massacre, like the one in Aurora, Colorado, we can safely assume that there is something abnormal about that person's brain," he says. "So I founded the Initiative on Neuroscience and Law, which brings together neuroscientists and lawyers and ethicists and judges and computer programmers to figure out how modern neuroscience will affect the legal system, how we think about criminal behavior and punishment, and new ideas for rehabilitation."
As if that weren't enough for one man, Eagleman spends his nights writing. Author of popular non-fiction works like "Incognito: The Secret Lives of the Brain" and "Wednesday is Indigo Blue," Eagleman is also known for his fiction. "Sum," a book of 40 short stories exploring the afterlife, is an international bestseller available in 27 languages.
It's a busy life, to be sure. But Eagleman believes having "lots and lots of ideas" is critical to the pursuit of science. Most will turn out to stink, he says, "but there are a few gems hidden in the pile there."
And when you find them, "that's progress."
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