What is non-sleep deep rest and how to practice it?

Recently, I listened to a podcast about Non-Sleep Deep Rest. This practice, also called Yoga Nidra, is a way to help the body relax and replenish dopamine levels. Dopamine is a hormone in the brain that is responsible for feelings of happiness and euphoria. Lower levels of dopamine lead to increased feelings of stress, irritability and anger. These levels are used up during the day and replenished through certain activities like good sleep, exercise, listening to music, meditation and spending time in the sun. Another factor that affects healthy dopamine levels is maintaining a good diet. One study had found that the practice of NSDR for as little as 10 minutes a day can help improve levels of dopamine.

So how do we go about doing a NSDR exercise? First, find a quiet place where you can sit or lay down without being disturbed. Close your eyes to help heighten your other senses. Take 3 to 5 slow deep breaths in through the nose and out through the mouth with your lips pursed. The exhale should be longer (preferably twice as long) than your inhale. This helps to slow down the heartbeat and focus the mind. With your eyes closed, picture a flashlight beam come over your body. Start with the feet and slowly move up and over the entire body in pieces. When the light touches part of the body, pay attention to the sensations both internally and externally on that part of the body. How does the leg feel? What do you feel touching your leg? As the light moves off that part of the body, allow it to relax more and sink into the floor a little more. Next picture the light broadening over the entire body. Sense the body as a whole and then as the light moves off, relax further.