Thank you mccoy for the contribution.
What do you remember learning from Matthew Walker that you found interesting?
Eric, too many things to remember!
But, non REM (without dreams) sleep has four stages, from the most shallow to the deepest slumber. During deep sleep there is a general maintenance of the immune system, the cardiovascular system and a cleanup of the amyloid plaques in the brain.
REM sleep, the sleep with dreams, is necessary for a healthy mental balance. People who forcedly deprive themselves from sleep have typically hallucinations, since the brain reclaims what's needed in the wakeful state.
Many other details on what happens during deep and REM sleep, like the mysterious 'spindles' in stage 4 sleep and the data transfer from the USB key of short-term memory, in REM sleep, to the hard-disk archives dedicated to long-term memory.
The author defends an optimal sleep length of 8-9 hours, with various motivations, first and foremost according to me the risk of fatal car accidents for those who drive, but also lesser mental efficiency, less focus, and unawareness of such drawbacks..
The early birds and the late owls as different genotypes. The owls are usually disadvantaged in modern society.
Dreams as a problem-solver mechanism, lucid dreams are present in a certain percentage of people, the serious problem of insomnia.
And much more, all extremely fascinating and full of take-home lessons, supported by technical literature.
Also, to be critical, I think maybe there are times when you can sleep less and with relatively small disadvantages, although not for long...
