The Deterioration of The Human Mind

There is a term that has been in my head ever since I started critically watching films and I can't remember where it came from. The term, which I use as a sort of category or trait for certain films, is "the deterioration of the human mind."

What does it mean? Well, I'm elated you asked and happy to describe it! 

In films that I designate as "deterioration of the human mind" films, there is generally a protagonist who gradually loses their grip on their own sanity or composure. This is a common element in psychological films, but I have yet to hear it pointed out as I frequently do. Because I recently had to lay my perceptions of this idea out, my explanation is fresh in my mind. 

When describing something like this, a list of applicable films is very helpful. So here we go.

My Favorite Deterioration-of-the-Human-Mind Films (by year)

• Invasion of the Body Snatchers (1956)
• A chilling portrait of the few becoming more and more powerless against the many and the increasing paranoia and fear Americans were bringing upon themselves. The characters unravel, the main character so much that (spoiler alert) he is reduced to a screaming, sweating mess by the apparent end of his terrifying ordeal.
• Vertigo (1958)
• One of the clearest and most well performed unravelings on this list, played of course by Jimmy Stewart in Hitchcock's classic mind-bender. Stewart becomes more and more obsessed and psychotic as the film progresses, becoming a desperate wreck with a looser and looser grip on reality and sanity.
• Psycho (1960)
• Well this one's bound to be on here isn't it? Well actually it kind of breaks the rules slightly. Because (spoiler alert) Norman Bates' psychopathy isn't something he gains slowly over the course of the film, which is usually one of the defining characteristics of a film's portrayal of a mind's deterioration. But, in perhaps what makes this such a legendary psychopath film, his insanity is revealed slowly, which has near the same affect! 
• Taxi Driver (1976)
• Brilliant for so many reasons, many being DeNiro's portrayal of a quiet man with a hatred for the scum of the earth. His hatred is exacerbated more and more, leading to a steadily increasing loss of sanity, making this one hell of a film for this list.
• Apocalypse Now (1979)
• It's kind of common knowledge Brando could be brilliant in just about anything, and as a severely power and control hungry general in Vietnam, he delivers one of the most haunting, cryptic, mysterious, and legendary performances of his career. But it isn't only Brando who makes Coppola's war masterpiece qualify here, for the entire film is an exemplary portrayal of the growing insanity Vietnam was becoming, which translates brilliantly into the play out of the entire film.
• Fight Club (1999)
• This may be the most outright human-mind-deteriorating movie on here, and without giving everything away, I will say that it is a brilliant film for many reasons, but for me the coming-apart psyche of the main character is just an excellent aspect of this great film.
• Memento (2000)
• Oh yeah, this is definitely on here. I won't give too much away, but this film definitely delves into how a mind works and how it can fall apart.
• Insomnia (2002)
• More Nolan psychological studies. Not as brilliant as Memento but very watchable nonetheless. Quality of the movie aside, it takes on a deteriorating mental state very well, especially with an unsurprisingly captivating performance from Al Pacino himself.
• There Will Be Blood (2007)
• Yeesh this one is a pretty sick look at sanity deteriorating, with a jaw dropping performance from Daniel Day-Lewis as one of the most unhinged characters ever portrayed on screen. 
• Moon (2009)
• More of a slow unveiling of a horrendous truth than a slow veiling of sanity, but still retains many elements pivotal to this breed of film. Sam Rockwell is astoundingly good here, and the film's understated terror and discomfort comes across beautifully (well, as beautifully as terror and discomfort can).
• District 9 (2009)
• A life falling apart, and a psyche in turn. One of the best sci-fi films ever made, and one of the best films in general. While the film attacks from many fronts, including racial divides and prejudice and alienation and paranoia, its central character, portrayed hauntingly but brilliantly by Sharlto Copley, has an unraveling that is unlikely to be forgotten.
• Chronicle (2012)
• A surprise stunner from early last year, this film managed to crash past the poor quality of many found-footage films of the past few years to deliver a smashing 80-or-so minutes in which a trio of teenagers' mysterious newfound powers lead them through confusion, discovery, acceptance, and finally, harnessing of their might. Andrew, played by Dane DeHaan, in one of the most unsettling performances of that year, sees as soon as he figures out the extent of his new capabilities that he can not only change everything wrong with his own life, but obliterate it all. It's an excellent film for many reasons, but the central character's slip into power-famished madness is as gripping as it is terrifying, making it a superb pick for this, my favorite of categories.

So that's my list right now of the best films that fall under this genre of mine. If there are others you can think of, I'd love to hear about it in comments. Happy movie watching my friends.