Evolutionarily, our minds aren’t naturally hardwired to remember complex math equations or codes (though it’s pretty cool that we can). “We’re programmed to remember things that have real meaning, as opposed to just a random string of numbers,” Milstein says.
So if you frequently forget your passwords, that’s actually more innate (and common) than you think. “Don’t feel bad about those things,” Milstein says. Especially when you have a million other tasks going on, random information like that easily gets trashed to make room for more important things.
However, “If the thing that we’re learning has meaning, if it has some emotional element to it (it’s funny, it’s scary, etc.), it’s more likely to stick,” Milstein notes. This is why you might remember every second of the last scary movie you watched, yet slip up on your best friend’s phone number.
So if you want to remember something simple (say, a string of numbers like a date or phone number), then you should mentally tie it to something silly or scary, Milstein suggests. “That’s the way you make those memories stick,” he notes. Dramatizing the numbers or using them in a silly sentence might help way more than you think.