Gamer Dementia

Coined by Ross Scott of Accursed Farms, it refers to when a video game makes you feel insane because something which you've done/seen before is now suddenly completely dfferent, or no longer works for seemingly no reason.

Jack: So how was Sonic Heros?
Ronald: God, so mixed, it was giving me serious Gamer Dementia!

Jill: Did you get through Hellgate London at all?
Steve: Fuck no, it seemed like I was going insane, stuff was randomly changing!
Jill: Sounds like it was giving you a real case of Gamer Dementia!