The Disorder:

If you have the unwavering belief a loved one has been replaced with an impostor (and you don't have the pimp mustache) you're probably dealing with Capgras Delusion. Besides being the name of band you were in while at community college, Capgras Delusion is brought on by that Molotov cocktail of brain disorders: schizophrenia.

The alleged impostor can sometimes be perceived as a threat or simply as a docile stranger who just happens to look exactly like your spouse and inexplicably wants to live their life. While most Capgras patients decide to live with the impostor, some rebel against the perceived takeover and try to fight it. They can become so paranoid that they even believe they themselves have been "replaced."

The question is, if you think you've been replaced, why were you not replaced with a fitter, more well hung version of yourself? We mean, as long there is a pretend "you" running around, that pretend "you" might as well get pretend laid more often.

The Movie:

Do you remember the Arnold Schwarzenegger remake of The Parent Trap called The Sixth Day? Where Arnold played a pair of twins that were the result of a guy being cloned against his will?

That scenario has also been the basis of more than one Star Trek episode, only there the clones tend to wind up with opposite personalities of the original, even to the point of assuming outright Evil Twin qualities. It's a classic mindfuck plot, since the one asshole in the universe none of us want to contend with is ourselves.

The Disorder:

For delusional victims of the syndrome of subjective doubles, that recycled old sci-fi plot becomes a stark and iron clad belief. Some people suffer it as another symptom of the above-mentioned Capgras delusion.

Sufferers of SSD maintain that they have a twin who looks exactly like them but has a completely different personality, presumably brandishing an evil twin goatee. Sometimes patients even allege there are multiple clones running around, or that their own personality has been copied and pasted into some stranger.

God forbid these people ever actually run into somebody who looks like them, or that they should come across that new Facebook app that has you upload your photo and then tracks down all the other people in the world who look just like you. We'll all have SSD before long.

The Disorder:

There are a number of diseases and parasites that inflict zombie-like symptoms on their hosts, but only Cotard's Syndrome makes a person actually wholeheartedly believe they are the living dead.

Cotard's is a brain illness that stems from schizophrenia, and those afflicted believe that they are truly dead, actively putrefying or altogether non-existent. Some patients even feel that they have lost all their blood and vital internal organs.

Not only that, but some reason being dead means they must be immortal, quite a logical thought coming from a delusional person. It's probably fairly harmless until you decide to test your invincibility by taking on a crime family. Or get hungry and decide you need a bite of a stranger's brains.

The Movie:

Groundhog Day answers the age-old question, "If you were Bill Murray and stuck in a time loop, what would you do?" The answer is give Chris Elliot a mountain of shit and relentlessly try to nail Andie MacDowell. After an undisclosed amount of time, Murray finally escapes the time loop either by learning love and compassion or huffing the copious amounts of Aqua Net coming off Andie MacDowell's enormous hair.

The Disorder:

Everyone has felt deja vu at some point in their life. Usually the experience only lasts for a few moments before it passes, but for some people, it never ends.

The condition is rather ingeniously called Chronic Deja Vu (high five, psychologists!). People with the condition become stuck in a world where every experience is a familiar one, even when it's impossible they ever witnessed it before, like getting your 20th vasectomy or seeing the Detroit Lions win the Super Bowl.

All jokes aside, the condition really does sound awful; all entertainment becomes pointless because even new movies have that boring sense of familiarity to them. You've never seen it before, but you get the annoying, bored emotional response of having watched a rerun a moment after you see it for the first time.

And here's the even bigger mindfuck: Sufferers tend to reject treatment because their condition convinces them that it has been tried before. And it clearly didn't work, so why bother?

The Disorder:

...unless of course you live with Aphasia. The disorder is characterized by the sudden lack of language comprehension or inability to speak clearly and is typically caused by a stroke. However, studies showed that Aphasic patients who could still form words were easier to understand if they sang instead of spoke. Even some who were totally unable to speak could still sing songs and communicate that way.

Living an Aphasic life (which incidentally sounds like a great title for a song from a Broadway musical) would be like living in a musical all the time, where even the most mundane aspects of communication are sung, hopefully in key and without the exuberant costumes. It probably sounds like fun, until you are really really pissed off and are trying to get someone to take you seriously.

The Movie:

In Night at the Museum, Ben Stiller plays a nighttime security guard at the Museum of Natural History. On his first night on the job, the once funny Zoolander star discovers all the museum's exhibits come to life thanks to a cursed Egyptian tablet also housed in the building (typical). Throughout the film, the various exhibits create comedic trouble as Stiller tries to control them. Hilarity kind of ensues.

Also see: any Pixar film where everything from toys to cars chat it up when humans aren't around.

The Disorder:

Your life can too be a humorless vehicle for the final death knell of Ben Stiller's comedic talent... that is if you suffer from Delusional Companion Syndrome. Imagine for a moment that every inanimate object around you was a sentient being, with its own hopes and dreams and could actually speak to you. For some victims of Alzheimer's disease, that is their everyday life.

Recently, psychiatrists have found a rare complication in Alzheimer's patients where the afflicted believe comforting inanimate objects such as a favorite Hummel figurine or a half-used tube of Bengay are sentient and chatty. While a home full of pals actually might seem like an improvement for a lonely old woman, it surely does give one pause when reaching for the toilet paper.

The Disorder:

If you wake up tomorrow and get the odd feeling that your bedroom is not in fact your bedroom but has been meticulously replaced by someone, odds are you are not in the Matrix but simply have Reduplicative Paramnesia.

It is a malfunction in the memory centers of the brain, normally stemming from some kind of head injury, that causes patients to believe a location they currently inhabit has somehow been duplicated. For instance, they may perceive that the hospital room they are lying in is really inside their dining room, while the real room still exists in the hospital, but is empty.

Sometimes they'll even believe the hospital itself is located in their home town when it actually isn't. When questioned as to how that could be possible, patients have explained that their current surroundings are obviously an exact copy of the real place and will further claim that the same staff work at both locations in order to complete the illusion.

Once more this condition is very rare, so keep that in mind if you intend to use it as an excuse to call in for work tomorrow ("Look, boss, you and I both know I'm already at work. It's not my fault you've disguised the Burger King to look like my apartment, and replaced the french fry station with an Xbox playing Call of Duty").

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For more from Cracked's Psych Department, check out 5 Mental Disorders That Can Totally Get You Laid and 6 Mental Illness Myths Hollywood Wants You to Believe.

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