But cognitive psychologists hope that asking what we remember will start to teach them how we remember. No scientist is perfectly sure how the brain physically sorts and stores all the information - and all the types of information - that gets encoded into memories. Memory still looms as a big mystery in science. While memory is what helps us recall things weвЂ™ve encountered or thought of before, studies of memorability ask: Why do we remember what we remember? Why do we forget what we forget? On any given day, weвЂ™re bombarded with images - in the news, on TV, on Instagram, faces we encounter on the street, scenes we see outside a car window - and some of those images stick around in our brains.

Courtesy of Wilma BainbridgeД«ainbridge wasnвЂ™t asking about my memory, but memorability. The women seemed to have equally kind smiles, so why would I remember one more than the other? And the beaches, well, they both seemed like boring postcards. ThatвЂ™s a place IвЂ™d want to eat a big bowl of pasta and laugh with friends. IвЂ™d choose the dining room with the tree over the sad office cubicle. He was more classically handsome with swooshy hair, deep-set eyes, and superhero-square jawline, compared to the smirking man in the top row (sorry, dude). Maybe, I thought, IвЂ™d remember the man in the bottom row if I saw him again. These were the kinds of mundane photos we may come across every day - two men, two women, a dining room and an empty cubicle in an office, two tropical beaches. None of the images seemed particularly striking. Wilma Bainbridge, a cognitive neuroscientist at the University of Chicago, recently showed me eight images and asked me to guess: Which ones will I remember? For each pair, she hinted, one image would be more likely to stick in my mind.

Part of the Memory Issue of The Highlight, our home for ambitious stories that explain our world.

My memory pictures