here in the USA what sets DID's apart from non DID's is the diagnostic criteria for DID. one of the diagnostic is about having memory problems but its a special kind of memory problem..the host/core meaning the person diagnosed with DID cant remember but when they switch into alters the alter remembers..

examples

I would not remember going to a parade but my alter Sunny would remember going to the parade because I had switched into being Sunny the day of the parade.

I would not remember where I lived, for how long and what I did there, but my alter Rainey would remember because it was Rainey that moved us to that address, it was as Rainey that I lived and worked there, so what I didnt know Rainey did.

I would not remember flying in an airplane but Twiggy would. I didnt remember it because I had a panic attack and switched into Twiggy. Twiggy would remember it because it was Twiggy that rode the air plane.

Non DID's dont switch into alters so they dont remember the same way we do. when they dont remember the memory is gone forever or that memory just wasnt important enough when it happened to remember it.

examples

a person coming in from work throws their keys on a stand. they dont need their keys until the next day so at that moment they dont need to remember their keys are on the stand. the next day they dont remember where they put their keys and look all over the house until finally they look on the stand on the way out the door.

Jane goes to a birthday party for John. Jane really doesnt care that John is 50 and is totally bored at the party. the party doesnt really matter to her, when she gets home someone asks how was the party all she can remember is how bored and disinterested she felt during the party. she doesnt remember john got a weed whacker from his father or other details. most of the details are gone from her brain because it wasnt important to her.