In just a few minutes of mental wandering, you have made several distinct round trips from past to future: forward a week to the important meeting, forward a year or more to the house in the new neighborhood, backward five hours to today’s meeting, forward six months, backward five years, forward a few weeks. You’ve built chains of cause and effect connecting those different moments; you’ve moved seamlessly from actual events to imagined ones. And as you’ve navigated through time, your brain and body’s emotional system has generated distinct responses to each situation, real and imagined. The whole sequence is a master class in temporal gymnastics.