For those who haven't seen the video here are some highlights of what Greyson says.
1. Wishful thinking, lack of oxygen, effect of drugs are not valid reasons for NDE's. They have been disproven to have any effect.
2. Mind is not the brain though they work in combination. Brain has evolved to help us in everyday life of survival, mating etc. It filters out higher level consciousness to focus on normal life and what is needed for survival.
3. Mind and brain combine in many ways to help us survive, interact emotionally and do our normal work.
4. Mind and awareness become sharper as the brain shuts down.
5. Psychedelic drugs merely shut down the basic functions of the brain which then allows mystical experiences to happen. Elaborate mystical experiences are associated with a decrease in brain activity not an increase.
6. When brain is shutting down consciousness seems to flower. Similar to yogis and people who meditate.
7. During NDE's people can describe accurately what was going on around them at that time.
8. People understand the importance of the golden rule during NDE's. Learn empathy and see the other person's point of view. When we harm others we harm ourselves. It is a natural law not just a religious guideline.
9. Time as we know it is not the same. Though things happen in a sequence they also seem to happen at the same time. Difficult to explain in normal terms.
10. People seem to live multiple lives at the same time (like in a multiverse).
11. We all are interconnected.
Just certain points I managed to remember from the video. Please do watch the video fully. Very insightful.