My wife acquired anterograde amnesia after a car accident. This device may or may not have worked for her: she would probably have discovered the device anew every time (as in, every 10 minutes or so), although she would probably be pleased each time.

Thankfully she fully recovered after a few weeks. It takes a lot of patience to deal with someone like that, and you could tell it frequently caused a lot of frustration on her part. Every 10 minutes or so in fact.