Activating a one memory activates others too.
What could you put in the box will actually make the box lighter, more of them you put in the box lighter it becomes?
Everytime when you come across something new your brain creates a pathway and the next time you encounter a similar situation your brain simply returns the existing pathway and eventually this pathway becomes a well worn route.
Your brain is continuously searching for anything that match facial pattern on file on your neural network and because facial recognition is key to being a part of community or tribe or just knowing friend or foe your brain is happy to put a face on just about anything.
In fact it reward itself in form of Dopamine.