What happens to memory during sleep?

Sleep is important for memory. We know that from multiple experiments. There's two aspects of memory that are really important. One is taking the information that you've had during the day and sort of tagging it for which ones you think are important to your survival. We don't really know how that process happens, but it seems to happen in this slow way. Sleeper non R.E.M., sleep. You know, you make these connections when you experience things and then they need to be reactivated to strengthen those Train tracks need to be activated to solidify, and they need to be activated when they're not getting new information because new information confuses it and it's written over almost like a computer. And then in REM sleep you get further activation and laying in of those pathways but connecting them to other memories that you have. They get distributed and connected to other parts of your brain. The hippocampus really critical for memories. The little structure looks like a seahorse, which is why they call it the hippocampus. The hippocampus is a critical structure of the brain, and we know that sleep deprivation really attacks the hippocampus.