We all know that a "good nights sleep" has dozens of benefits for you health and mind, but sometimes the details of those things can be a bit hazy!
Memory and the way it functions within our brains is a huge beast that isn't fully understood. On the basic level, your experiences and memories are first saved into short term memory storage. Then, different sleep stages save it into long term storage over night or your sleeping cycle. The video explains this point more in detail
What it doesn't explain, though, is that the fact of the matter is not that you need "more sleep." For some people, it may. Each person's body falls into different sleep stages at different times and rates. Some people might be able to hit REM sleep within 2 hours of sleeping, others take 3 or 4. Some cycle through many REM cycles per night. While there are some averages and generalizations that can be made, it's more important to remember that each person is unique in this!
So, pay attention to the way that your body reacts to sleep. Do you function best at 5 hours, or at 8? Do you feel too groggy at 9, or too exhausted at 6? Know your body, and then pay attention to signs of good procedural or declarative memories, too. These may be harder to catch, but once you know the way your sleep is functioning, you'll be able to better set your schedule to allow your sleep to best benefit your memory.