Jeff Emtman is the creator and host of Here Be Monsters.

"You can think of your memory as a box full of photographs, like the ones your parents have in your basement. Just like old glossy prints. ... And unfortunately, when you pick up an old photo print, what happens is you always leave a thumbprint on it, and overtime your memories become more and more thumb-printed. So if you pull up a memory enough times, you’ll just be looking at your own unique thumbprint."