How does our brain know we forgot something, but can’t remember what it is?

Question

Sometimes it takes me to backtrack my thought process until I remember, sometimes it randomly comes back. Sometimes it doesn’t. Why?

In: Biology

Answer 1

If the memory is inside a box, your brain can see the box and know there is something, but not be able to open it for a while to see what’s inside. When you’re retracing your steps, you are re-making more connections and hopefully one of those opens the box.

It’s similar when you see someone you met previously. The face (image) is stored in one box and the name in another box. You recognise the face, so you know that you know their name but you can’t open the other box. Only once both memories are firmly set can you open both boxes.