A repressed memory is a memory of a traumatic event that your mind purposefully forgets in order to protect itself, but in theory the memory never really goes away, it instead enters your subconscious, where it creates anxiety, depression, and self-sabotaging behavior.

Some therapists believe that reviving these memories can help people deal with their issues, but sometimes these memories involve childhood abuse at the hands of people they know, people who often get prosecuted on the basis of these repressed memories.

And this is where things get hazy because many researchers don’t think that repressed memories are really a thing. They also point to the fact that it’s a fairly modern phenomenon, and it’s possible people are actually remembering events of sleep paralysis, where waking people experience vivid, often terrifying hallucinations.