Dreams and Memory

Dreams, "inside" phenomena, and input that enter through the senses are stored in the brain the same way and are treated the same way. Essentially, the brain cannot tell the difference. This explains why dreams are so real, especially nightmares. When you have a physical response while awake, that same physical response will be the same when you dream about it. The mind thinks what it is experiencing is real, that is it is happening outside the brain. This also probably explains the psychosomatic principle. This sometimes can be a problem too. For instance, confusing memories for stored dreams.

People can make an effort to notice when they are dreaming. By noticing weird events, trying to levitate, etc. I am referring to the practice of lucid dreaming. Lucid dreaming is hard, and not easy to do but it can be done through practice. You kind of lose this ability when you get older. I do not do it as often as I used to.