A psychology concept I will remember five years from now is the four stages of sleep and REM sleep. I found it interesting that that our brain experiences different waves in each stage of sleep, starting with theta waves and then moving into sleep spindles, K complexes and then to delta waves in stage 3 and 4. I was surprised that REM sleep is where all our vivid dreams take place and that after 15-30 minutes of REM sleep our brain starts the cycle all over again. What I found most intriguing while learning about sleep is that in order to feel fully rested in the morning we need to experience stages 3 and 4 of sleep and by having several drinks before bed it can make us feel more tired in the morning because alcohol suppresses delta sleep. I had always wondered why kids had more energy and seemed overall less tired than adults, I found out children spend 40 percent of their sleep in deep sleep whereas adults only spend one-quarter of their sleep in it. For years I have struggled with sleeping at night and I found it compelling to learn about the different levels and processes my body goes through in a night of sleep.