1: It was the early 1990s. Scientists surgically positioned what looked like “a small joystick and dozens of wires” into the skulls of a group of rats, writes Charles Duhigg in The Power of Habit.
Their goal? To be able to observe in minute detail what was happening inside the brains of rodents.
Each animal was then placed in a T-shaped maze behind a partition with chocolate at one end. … continue reading