Maybe just call it Sanity Mechanics or Psychological Impact or something like that? Few games simulate actual mental health problems, and many amount of players will suffer or have suffered or have family suffering from real world mental health problems, so I'd avoid that term.
IIRC it's just stress in Blake's 7 (although it should have been called Space Fatigue in that game). Stress would make sense, medically speaking, as the different manifestations are still all due to the same thing.
Running the risk of premise rejection, this classifies genre only, not play-style, is that right? So (to stick with the post immediately above me) GURPS, TORG, Fate and Universalis would all be in the same category - I'm not sure how helpful that is. It feels a bit like most indie/non-trad games are going to be disenfranchised by this - if your taxonomy either excludes these games or lumps them in with games of the same genre (so that WoD Vampire and Urban Shadows are in the same box) I'm not sure how useful it is generally.