system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do we retain memories if all of our cells replace themselves after a small amount of years?
gpt
The concept that all your cells regenerate within 7-10 years is based on some misconceptions. Different types of cells regenerate at different rates. Some only last a few weeks while others last your entire life. Most of your brain cells are in the later category. The 7 years is based on an estimated average of all your cells.

And while we do not know much about how memories work there is some evidence suggesting that memories gets refreshed when you are asleep so that even if brain cells do not last your entire lifetime but gets damaged somehow the memories will get restored and refreshed from time to time.