I relinquish control of my atoms, at least to whatever extent I controlled some of them prior to death. And I no longer perceive or think or remember.

If I could reincarnate into anything other than a human on earth, I'm not sure I'd want to retain memories of a past life. I'd hate to poison a new and different life with the baggage of a human lifetime, for better or worse.

Mind uploading or cryonic preservation for possible future revival and treatment is a nice thought, but I would hate for evil billionaires to be able to cheat death, that seems like too big a tradeoff.