Sometimes your thoughts wake you up; you get out of bed, pacing or writing or reading until you're finally weary enough to sleep.
Or maybe you keep thinking while you're awake about a situation confronting you, over and over and over again until you're weary from the nonstop churn in your head.
It happens to a lot of people, trying to get some peace from their own thoughts.
Nancy Colier is both a psychotherapist and a spiritual counselor, and she draws from both fields for her book Can't Stop Thinking: How to Let Go of Anxiety and Free Yourself from Obsessive Rumination.
We bring the author in for some help in finding the off-switch for our brains.