Columns > Published on September 17th, 2013

It's Made Of SCIENCE: Multiple Personalities

The suspense hangs thick in the air. Of your ten characters, only two remain, staring each other down. Each knows he didn't kill the other eight. Each knows the other must be responsible.

The lights flash, and only one is left standing.

Trigger montage. Flashbacks, hidden clues, offhand comments. No, it can't be...

Yes. The last man has multiple personalities, and has been the killer all along!

How... shocking? Is that how it works? Is this an actual explanation, or something supernatural passed off as a realistic crime thriller?

Starting this article wasn't easy, because I feel like there are several important facets about multiple personalities that need to be addressed straight-out. With the lack of creativity that occasionally plagues those of us meeting a deadline, here are all of them in no particular order:

  • Schizophrenia is not the same thing as multiple personalities. Schizophrenia is not the same thing as multiple personalities. Schizophrenia is not the same thing as multiple personalities.
  • This article will have SPOILERS, but the examples I use will all be over a decade old, so I don't feel bad about it.
  • I am not a medical professional. This article is designed to help you deal with multiple personalities in your fictional characters, not to make a diagnosis or become a professional on the subject.

For the record, much of the sourcing here is going to come from the DSM-IV, which is sort of the psychologist's guide to diagnosing mental disorders. The DSM-5 came out earlier this year, but in regards to this subject, there aren't any real differences relevant to this article. If you're interested, you're free to review the changes between the versions.

What is dissociation?

Multiple personalities has nothing to do with schizophrenia. They aren't even in the same class of disorders.

In order to talk about Dissociative Identity Disorder with any sort of clarity, we need to first look at the disorder's family.

In the DSM-V (the current mental health diagnostic guide), Dissociative Identity Disorder (DID) is classified in a group unsurprisingly called the Dissociative Disorders. It's fairly small and mostly comprised of disorders you probably haven't heard of, but the underlying theme is that the dissociation experienced is not otherwise caused by drugs or other mental issues such as PTSD.

I would give you a definition for what dissociation actually is, but at this time, there really isn't any clear consensus. The best I can do is say that dissociation involves the connections between consciousness, memory, identity, and perception. Dissociation isn't about a problem with memory or identity itself, but rather how all of these things relate to each other within an individual. For example, if someone feels like they've woken up in the wrong body because they don't feel that their memories belong to their identity, that's a dissociative problem.

Dissociation is typically measured on a continuum, and you've almost certainly experienced some degree of dissociation in your own life. Have you ever daydreamed? Read a book so intensely that you forgot where you were? Nearly gotten in a wreck because you were texting while driving? Been drunk? Then you've experienced some degree of dissociation. Now imagine that this type of disconnect happens to an extent that it cripples your identity, memory, and very sense of existence, and you'll get an idea why dissociative mental disorders can cause some serious problems.

What is Dissociative Identity Disorder?

That's a tougher question than The Internet will initially tell you, because DID is incredibly controversial. Nobody can agree on whether it exists, what causes it, at what age it typically can be diagnosed, and so forth. The fact that it is incredibly rare doesn't help. Truthfully, we really don't know nearly as much about it as we do most other disorders, which is perhaps why it's such a ripe trope in fiction.

Formerly known as Multiple Personality Disorder, DID is diagnosed in individuals where they present more than a single distinct identity or personality, and control of the body is shared amongst the host and these "alters." Each personality will generally show a varying degree of memory lapse that can't be explained by normal human forgetfulness. As with all dissociative disorders, this behavior cannot be explained by drugs or other medical conditions (like seizures).

Most sufferers of DID will have on average ten personalities, though it can range from two to hundreds of separate identities. The primary personality, the one with the individual's given name, tends to be submissive and withdrawn, while the alternate personalities are typically more aggressive and controlling, and contrast with the primary. Memory loss is common in DID, where the primary personality will have difficulty remembering events that took place while an alternate was in control of the body. Often, some memories will be available to the alters that the primary will not be able to recall.

What causes DID?

That depends on who you ask.

The official ruling so far is that DID is caused by extreme trauma, normally during childhood. The abuse is so severe that it prevents formation of a coherent identity, resulting in memory fragmentation. The individual cannot handle the memories of the abuse, so alternate personalities are formed to "store" these memories and handle other life aspects. Essentially, DID forms as a type of coping mechanism to help the sufferer deal with what they experienced as a child.

Another camp, however, posits that DID forms as a result of treatment for severely dissociative individuals.

It has to do with that dissociative spectrum I mentioned earlier. People with DID are assumed to be incredibly dissociative, so much that their identity is fragmenting and they're losing control of their behavior. The argument goes that if you slide far enough down this dissociative gradient, you end up dissociating so badly that you start to lose control of your own behavior.

Such individuals would very susceptible to input from clinicians, such as a suggestion that a person is acting like they have multiple personalities. This would make DID an iatrogrenic problem; that is, one that is caused by the attempted treatment. Essentially, physicians might be taking suggestible individuals with real problems, and by suggesting there are multiple personalities, actually create these personalities within their patient. That's one of the claims made about Sybil, the book that (somewhat fictionally) covered the most famous case of DID in Shirley Ardell Mason.

There is some evidence that outside input may have some effect in the presentation of multiple personalities. For instance, it typically seems to take anywhere from a few seconds to a few days for a personality to switch completely in dissociating individuals. In India, however, DID patients will often only switch personalities upon waking up, which is how the disorder is typically portrayed in their media.

The debate is out there, but I need to stress that neither side is saying that any of these DID patients are lying or looking for attention. Diagnosed individuals definitely have dissociative problems, and are not assumed by anyone to have control over what occurs during an episode where an alternate personality is presenting. The debate concerns where these personalities come from, not whether they exist.

What about schizophrenia?

Multiple personalities has nothing to do with schizophrenia. They aren't even in the same class of disorders. So calling your character schizophrenic when they present with multiple personalities is by definition incorrect.

There are probably a lot of contributing factors to this misconception. Schizophrenia actually means "split brain," but the term relates to disorganized thoughts, not split personality.

My guess is that characters with multiple personalities are often portrayed inaccurately in fiction, where the alternate identities are shown as visible people who can interact with the primary personality like an imaginary friend. The truth isn't as dramatic. While DID patients are known to hear voices, they tend to recognize these voices as part of themselves (internal), as opposed to schizophrenics, who believe the voices come from external sources. Visual hallucinations in the form of walking, talking people are very rare, even in psychotics.

There's a good reason why I'm drilling into this difference between schizophrenia and DID. It's reasonable to write a schizophrenic character interacting with a hallucination, unaware of its true nature. However, you can't really do that with someone who has multiple personalities. It's possible they may not be aware of their alternate identities, but they'll never hold a conversation with an alternate identity without being aware that they're talking to themselves.

Hey Nathan, I think there's an elephant in the room...

Yeah, yeah. Fight Club, written by LitReactor patron saint Chuck Palahniuk, features a protagonist who has an alternate personality in the form of a domestic terrorist (uh, spoilers on seventeen year old book, I guess?). No, the character is not portrayed with a medically-accurate depiction of dissociative identity disorder.

But does it matter?

The purpose of fiction is to entertain, and one way to entertain is by describing the unusual. Sure, it's unlikely that someone will suffer from both psychopathy and DID, but nobody complains about Psycho. If Fight Club wants to feature the protagonist beating himself up while one side of him tries to diffuse bombs set by the other, why not? It was an awesome story, and the accuracy of the diagnosis really wasn't relevant. Not that the character was ever really diagnosed with DID, anyway.

It comes down to whether or not you intend to have a character with multiple personalities, or whether you want a character with dissociative identity disorder. If you want to write a realistic book that features a character with true multiple personalties, then you probably should do the research to get it right. If you're just looking for symbolism, or writing a satire, or just want a twist that you think nobody is going to expect, then the gloves are off, and you can manifest the doppelgangers in any way you want.

Just realize that the further away from reality you get, the more your twist becomes a deus ex machina ending to anyone who took Psych 101.

On a personal note, I'm finding the trope to wear a bit thin. Psycho surprised me, and then Fight Club surprised me again. After Secret WindowHide and Seek, and Identity, the concept of the nice guy having crazy alternate personalities feels like cheating us of a better solution to the mystery. Write about multiple personalities all you wish, but just don't be disappointed if I shrug off your surprise twist at the end.

Do you have an idea for my next science-themed article? I'm taking suggestions! Drop me some topics in the comments, and if I like it, and feel that I either understand or can research it well enough to explain it, your idea can be the next IMOS article. Also, feel free to call me out if you spot an error anywhere; I'd rather have a perfect article than a reputation for being perfect.

About the author

Nathan Scalia earned a BA degree in psychology and considered medical school long enough to realize that he missed reading real books. He then went on to earn a Master's in Library Science and is currently working in a school library. He has written several new articles and columns for LitReactor, served for a time as the site's Community Manager, and can be found in the Writer's Workshop with some frequency.

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