In DC Comics, The Flash might be a super fast speedster that can help defeat the latest villain in a fraction of a second, but being that fast also poses a pretty big problem for his own brain. Able to sprint around the globe in mere seconds as well as give Superman a literal run for his money in terms of speed, The Flash can use his Speed Force powers in all sorts of ways that don’t always relate to the physical act of running or beating criminals to a pulp.

Revealed way back in The Flash #171 by Geoff Johns and Scott Kolins, the holder of the Flash mantle at the time, Wally West, is shown to be doing his best to try and help the police figure out an unnerving new wave of crime that sees survivors of Flash’s past heroic deeds murdered in cold blood. Convincing the authorities to let him comb over the various crime scenes, Wally knows he’s no forensic scientist like his predecessor, Barry Allen, so he takes it upon himself to blaze through a handbook on the subject to get his knowledge up to snuff.

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But as explained here, Wally – and by extension the entire Flash Family – can’t simply just read an entire book in seconds and expect to remember it all for the rest of his life. And although having the ability to read an entire library’s worth of literature in the time it takes a normal person to blink might sound like a pretty sweet deal, there’s a glaring problem with doing so that isn’t always touched on, yet is made abundantly clear here.

The Flash speed reaeding

Pulling out a handbook on forensic science as he rushes from crime scene to crime scene, Wally is able to blast through the entire novel in about ten seconds, a feat that is surely as impressive as it sounds. But the issue here is that Wally has to, “read it three times more to get it to register,” a problem considering Wally goes on to say, “It’s like cramming for those school exams. I learn it quick, and forget it quicker,” succinctly telling fans point blank why Wally’s super speed isn’t all its cracked up to be when used for learning purposes.

Basically calling to attention the fact that this highly advanced form of learning isn’t doing his brain any favors in the retention department, the idea that any version of the Flash could quite literally utilize their Speed Force powers to learn all there is to know in the world, only for a fraction of that to be held in the soft, squishy folds of their brain, is an issue for a hero that constantly needs to be at the top of his game not only physically, but mentally as well. Luckily, and as Wally insinuates in this issue, utilizing the knowledge gained as quickly as possible still allows that information to be helpful, but as Flash has found out over the years, it won’t last forever and he needs to be quick about implementing it.

So even though The Flash’s super speed allows him to cram information into his head at a blistering rate, it isn’t always good for his brain when most of the information goes in one ear and out the other depending on how long he waits to act on said info. That being said, Wally and all other Flash Family speedsters can still take a few seconds out of their day to read the entirety of whichever book they so choose as many times as needed, it’s just a bit of an issue when their brains can’t always keep up.

Next: Flash: The Scarlet Speedster's Fastest Ever Comics Villain