Imagine that for twenty years you have known a well-respected member of your community. He’s a devoted husband and father, a doctor in a high position with the World Health Organization, and a trusted friend and neighbor. Now imagine one day you wake up to the news that he, over the course of the past several days, has calmly and systematically murdered his parents, his wife, and even his two children. Imagine that you then learn that almost everything you have believed about this man for the last twenty years has not been true. He has never had a job at the World Health Organization. He never graduated from medical…

Why is it that as soon as you’re hit with the scent of a certain flower, a specific brand of perfume, your mom’s home cooking, or firewood burning somewhere in the distance, that a flood of memories and emotions come rushing through you so powerfully that it’s almost as if you took a trip back in time? The simple answer is that the sense of smell is the one sense that’s more closely tied to memory than sight, hearing, taste, or touch. Here’s how it works. Humans have around 400 types of scent receptors that are capable of identifying one trillion different smells. Although science hasn’t quite been able to…