In my new book, The Fold, Mike Erikson is blessed (if you can call it that) with an actual photographic memory. Just like Reed Richards or Batman or dozens of other sci-fi characters, he can glance at a room and years later tell you every book that was on the shelves.
The catch is, what we generally think of as "photographic memory" doesn't exist. At least, no one's ever passed any sort of rigorous scientific test for it. There are many forms of amazing memory out there, but none of them work quite like the classic comic book standby.
For example, eidetic memory is the ability to remember images in perfect detail after a very brief exposure. It's probably the closest, in theory, to what we think of as photographic memory. While it's quite common in young kids, it rarely survives into adulthood. Even when it does, there's a fair bit of debate about how durable these memories are in the long-term.
There's also what's called "exceptional memory," where people can remember huge swaths of their lives, but it only seems to be on a direct, personal level. They could tell you that March 31st of 1999 was a Friday and they spent it at the movies eating popcorn that had too much salt… but they might not remember what the actual film was about (computers, maybe…?) or what other movies were playing at the time. There are a handful of confirmed cases of exceptional memory, but many of them are almost considered a disorder.
Still… if someone actually had sci-fi-trope photographic memory, how would it most likely work? I read up on different cases and tests to get a better sense of how these types of memory worked. And a few ideas hit me.
One was that someone with an actual photographic memory could make amazing mental constructions. Lists, pictures, even elaborate 3-D models—all the things we normally can't manage because they become too complex. But this hypothetical person would remember everything. They could compose a three page grocery list in their head, or design a huge LEGO set (if that was their sort of thing).
About this time I realized how cluttered a brain like this would get. Granted, none of our memories stay front and center in our conscious minds, but they leap forward when we're faced with a question or some form of reminder. And if someone could recall everything, then almost any trigger would set off a wave of associations and memories. And each of these remembered images or sounds would bring a wave of recollections with them as well. Hell, it wasn't hard to imagine that something could spark memories of remembering about memories. It would be like a swarm of insects buzzing constantly in your head, or two ant colonies at war across your mind.
Then I realized if someone with this memory had this same thought, they'd never be able to forget it. Every time they were hit with a wave of memories they'd remember the comparison and it would bring that image of an ant swarm. It would become a near-permanent fixture in their conscious mind. One they'd have to adapt to and use, hopefully without making their mental situation any worse.
It was about then that I realized a perfect memory would be kind of horrifying. Remembering everything sounds great, but not being able to forget anything… that sounds kind of like hell. Bad breakups. Broken limbs. Moments of terror or panic. The death of family and friends. All of them trapped in your mind forever. Always fresh. Never fading. Triggered by a random sound or smell or sight.
So maybe it's not a bad thing when my brain loses a birthday or a dentist appointment now and then.