The TVTropes Trope Finder is where you can come to ask questions like "Do we have this one?" and "What's the trope about...?" Trying to rediscover a long lost show or other medium but need a little help? Head to Media Finder and try your luck there. Want to propose a new trope? You should be over at You Know, That Thing Where.
While I do not think there is a trope exactly like that per se, Epileptic Flashing Lights' name seems to reinforce the common misconception that you mentioned.
Convulsive Seizures is a related trope about another common misconception about epilepsy.
One option would be to make a note about how the "flashing lights=epileptic seizures" is not totally accurate either as a real life example on the Epileptic Flashing Lights page or in its description.
"irhgT nm0w tehre might b ea lotof th1nmgs i dont udarstannd, ubt oim ujst goinjg to keepfollowing this pazth i belieove iN !!!!!1 d
If you know something about epilepsy, you could add a page to the Useful Notes section. That would be a public service
If it's the misconception in itself, it would most likely fall under Did Not Do The Research or Artistic License – Biology, since this would probably not be considered a trope per se.
Edited by Gamebreaking Deep into that darkness, peering, long I stood there, wondering, fearing, doubting, dreaming dreams no mortal ever dared to dream before.
Is there a trope for "flashing lights = epileptic seizures", which seems to be a common misconception, or at least a widespread joke? While flashing lights can trigger epileptic seizures, most cases of epilepsy do not have specific triggers for the seizures.