> Another sad thing is that we lose our memory in a step function. We remember something for a long time without using it, and then all of sudden it's gone from our memory.

Not sure memory loss is quite that binary. Heading for mid-40s here, and often things are still there, but it's higher latency to fully recall it. A bit like it's stored off in Amazon Glacier. Or often I can get the first byte quickly ("I know that person's surname starts with a P") but retrieving the full answer takes longer and some brute force iterations. It's as if I've hit a hash-table collision and need to binary-compare the results, or I've reached a node in a tree-structure that has many branches ("Is it Pfeffle? Piper? No, Pfeiffer!")