What Happens When We Sleep?

When i sleep, my body rests instead of get some kind of recharge, and my mind is largely blank because i'm nonconscious. And then i wake up in the morning. So, you know, no wonder i don't really get concerned if i lose an hour of sleep or two hours of sleep, because it's just my body resting. Nothing could be further from the truth. Your brain goes on an incredible roller coaster ride in and out of these different stages of sleep throughout the night. It keeps cycling in that way. That cerebral war between non rem and rem is won and lost every 90 minutes and replayed every 90 minutes. Now it's 90 minutes in humans. A,