The human brain has developed complex ways to let us know when we’re in danger and to help us escape that danger. These systems have saved countless human lives throughout history, allowing us to evolve into the sophisticated beings we are today. The dangers are different today, but we still have the same basic alarm systems in place that we did thousands of years ago. That’s how effective they’ve been. The flip side is, though, that while the world around us has changed our bodies are the same. These same systems that alert us to danger and give us what we need to get away can end up harming us in ways that can be hard to understand and even harder to heal.