Dreaming is what we do every time we sleep even if we don’t remember our dreams. there are three stages in sleeping, in the first stage: Our eyes are closed, but it’s easy to wake up. This phase may last for 5 to 10 minutes. The second one: We are in light sleep. Our heart rate slows and our body temperature drops. Our body is getting ready for deep sleep. And the third one: This is the deep sleep stage. It’s harder to rouse ourselves during this stage, and if someone wake us up, we would feel disoriented for a few minutes. This first three stages are called NREM sleep (non-rapid eye movement), during the deep stages of NREM sleep, the body repairs and regrows tissues, builds bone and muscle, and strengthens the immune system, followed by the REM sleep which happens 90 minutes after we fall asleep. The first period of REM lasts about 10 minutes. Each of our later REM stages gets longer, and the final one may last up to an hour. Our heart rate and breathing quickens and it’s the phase where we have intense dreams since our brain is more active. We may experience nightmares among those dreams. But the fascinating thing about nightmares is the reaction of our brain. Research has shown that a lot of dreaming occurs in the visual cortex, which is linked to the amygdala (an emotional response center). During a nightmare, the amygdala sense the fear in the person and cut REM process, so both of them, the visual cortex and the amygdala, get fired up and trigger autonomic arousal of the body, (the heart starts beating faster, breathing becomes labored, and we can start sweating profusely) we wake up in a panic. That means that thanks to the amygdala we may come out of a horrible nightmare which we wouldn’t be able without it! How fantastic!