Comment by dwd

Given the number of neurons, hash collisions are inevitable? /s

Our model of the world, and this includes "memories" is very highly compressed, and extremely lossy. We reconstruct everything from what neurons activate when we recall something, so it can also be like a corrupted zip, where we don't access everything required in the moment. This can be affected by sleep, stress, hormones, etc.

What is quite interesting is when we try and recall something and can't, but the subconscious processing continues and you recall it later.