James McAvoy's performance in the 2016 film Split, is nothing short of fantastic. The thriller is set mostly underground, which turns out towards the end as a tunnel lying beneath a zoo. It is the story of Kevin Wendell Crumb and his life with his twenty-three personalities. The story commences with the kidnapping of three girls by Kevin, when the body is taken over by Dennis, one of the more meticulous and formal personalities. The story proceeds to reveal several more personalities, with Patricia being the disciplinary mistress and Hedwig being a child afraid to be scolded. Dennis, Patricia and the other personalities plot to protect Kevin and the three girls from the emergence of the hidden twenty-fourth personality, which transpires to be a human-eating monster. Needless to say, it's scary and is fit for Halloween viewing.
The poster of the film Split (2016), extracted from: https://d13ezvd6yrslxm.cloudfront.net/wp/wp-content/images/2017-bestposter-split-700x1082.jpg.
This film brings to the fore one core pathology: dissociative identity disorder, or DID for short. Mostly, when people talk about psychiatry, we instantly think about depression, schizophrenia, anxiety disorders and phobias. Rarely do we think about people having multiple personalities. The lifetime prevalence of the disorder is estimated to be at 1.5 per cent. [2] Indeed, we sometimes turn a sceptical eye to individuals reporting that they've got multiple personalities and cannot get things done since personality A conflicts with personality B. We are prone to comment that they're 'pretending' or 'fantasising', or merely reasoning their way out from glaring inconsistencies in their reasoning. True enough, in an editorial published on the British Journal of Psychiatry, it recorded two models postulating the pathophysiology of DID - (1) traumatic model, and (2) fantasy model. [2]
The traumatic model suggests that DID originates from extreme childhood trauma, where the patient undergoes a process called dissociation. It is an adaptive mechanism rooted in psychology. When an event occurs that is too traumatic and horrendous to handle, the mind and body detach themselves from the event, treating as if it never happened. For instance, in the patients (who are murderers) recorded in a study published on the American Journal of Psychiatry [3], they all experienced adverse events amounting to torture. One of them was dressed as a girl during childhood by his grandmother and presented to his grandfather for sexual gratification. The same patient was also prostituted by his stepfathers. Another patient went on to be forced to commit incest by his mother with his sisters. Other patients experienced the same degree of physical, sexual and emotional abuse. In face of all these traumatic events, the body cannot stand their impact. The body loses control and predicts that it will lose control by attempting to resolve them. The ultimate way is to hide. In Suzanne O'Sullivan's genius book, It's All In Your Head, she described dissociation as a coping mechanism. Moreover, she went on to describe theories put forward by eminent psychoanalyst Sigmund Freud and other prominent psychiatrists in the past. It was hypothesised that the subconsciousness was the area where such memories were consigned. Similar to the subconsciousness portrayed in Disney production Inside Out, it is where one's darkest fears are all located. When one experiences trauma, the event is still present in the mind. It is just brushed away from the surface, or consciousness. Consciousness and subconsciousness are two separate tracts which can influence each other. That's why there are occasional word-slips which portray one's subconscious desires. For example, asking a girl if she wants 'toasted bed for breakfast' instead of 'toasted bread for breakfast' might indicate one's sexual attraction towards her. This is suppressed by the conscious mind but is alive and pumping in the subconsciousness. Going back to Split, we also see signs of support for the trauma model. Kevin Wendell Crumb was portrayed as a solitary, dismal character where he was subjected to (as shown in multiple scenes) physical violence. He was traumatised by the maltreatment by his parents.
Diagram illustrating the Iceberg Theory, which explains the correlation between consciousness and subconsciousness (extracted from: https://eagletraining.co.uk/wp-content/uploads/2020/04/The-Iceberg-Theory.png)
However, the trauma model, albeit being a very plausible model, is not generally accepted by the psychiatric community until now.
Many subscribe to the 'fantasy model'. It is simply the easy way out since it does not entail a long list of questions the traumatic model does. The fantasy model merely states that these patients are 'making up' all the additional personalities. They fantasise about an alternative life, bordering on the area of malingering. Malingering is not exactly a medical condition - it's simply a label we give to individuals who fake having an illness and present to the clinic with some pseudo-symptom. Suzanne O'Sullivan recalled an individual faking paralysis in front of her in order to get a doctor's certificate so that he could sue his employer. However, fantasising about alternative lives is not, strictly speaking, malingering. A line can be drawn. By imagining different lives and personalities, this can be construed as a sign of dissociation and derealisation. This can be traced back to certain life events that occurred which prompt the patient to escape. Since an 'actual', external escape cannot be actualised, the soul breaks free internally. The fantasy model has one major caveat though. It dismisses the suffering of the patients who are afflicted by such harrowing experiences. It reverts psychiatry to its darkest hour, the time when it was dismissed as a scientifically 'less rigorous' specialty in medicine. The time when it was merely a guessing game. Following modern developments in the field of neurology and neuroradiology, psychiatry has revolutionised itself. Instead of confining itself to the patchwork of rules and symptom-guessing games of the past, it rebranded itself as a rigorous discipline which had its own research and serves to promote better patient care and more promising outcomes.
The use of radiology in the analysis of patients with psychiatric disorders has completely dismantled the fantasy model, in great favour of the traumatic model. In the editorial [2], evidence has been shown in multi-participant studies that DID patients exhibit different brain activation patterns when they are controlled by different personalities. Remember, one's brain patterns cannot lie. DID patients also display brain activation patterns similar to those with Post-traumatic Stress Disorder (PTSD), who experience some form of dissociation after having experienced an intensely horrid event. Chalavi et al (2015) [7] showed negative correlations between hippocampal volumes and childhood traumatisation. Given that hippocampi are found to be 19.2 per cent smaller in DID patients than the normal population, explaining logically why DID patients experience amnesia of the traumatic events (the hippocampi are used for synthesising new memories, as according to the Standard Model of Systems Consolidation), the traumatic model can be shown to be reflective of the true pathophysiological origin of DID. [8] However, there remain certain issues rendering such a straightforward deduction not entirely safe. Firstly, most neuroimaging studies have small cohorts. This is totally understandable. It takes a lot of time to scan one's body, especially the brain. This is even truer when it comes to functional MR imaging, which is crucial for exhibiting one's brain activation patterns. The use of small cohorts is by no means discouraged, since they also have their utility in displaying possible correlates of a condition. However, a correlation can only be trusted if the results are replicated in multiple studies and cohorts. Secondly, brain activation patterns are very fluid. They show us what happens at that moment but give us no inkling as to why it actually happened. For instance, a person can see a bear and think about the one time he nearly got mauled. The person's activation pattern sequence might go something like this: amygdala (fear control centre) --> occipital and temporal cortex --> prefrontal cortex. Through logical deduction, we can say that seeing the bear has triggered a primordial fear reaction. There is a recall, through the activation of the occipital and temporal lobes, of the sensations pertinent to that memory. The prefrontal cortex then makes decisions as to whether the person should run or stay, and whether it's safe to do the latter. However, this remains a logical deduction - at best, an educated guess. In truth, we don't know why that sequence has popped up. The similarities in brain activation patterns between DID and PTSD may be purely coincidental and cohort-specific.
An article published by Reinders from King's College London [9] postulated a third position - the iatrogenic position. That article put forward two ways DID can be contributed by therapeutic interventions, respectively (a) through subconsciousness and (b) consciousness. This focuses mostly on the use of Cognitive Behavioural Therapy (CBT, or talking therapy using laymen's terms) instead of polypharmacy (like the use of antidepressants and anti-psychotics). Through consciousness, the patient is aware that he or she has to satisfy the therapist that he or she has DID. The patient therefore proceeds with portrayals of different personalities, such as writing differently and acting in drastically variant ways. This is, considered generally, a sign of malingering and is also classified as 'pseudogenic DID'. This is a very polite term for 'faking it'.
Artwork Illustration of Dissociative Identity Disorder - Inktober (extracted from Bored Panda, URL: https://www.boredpanda.com/for-inktober-i-focused-on-mental-illness-and-disorders/?utm_source=google&utm_medium=organic&utm_campaign=organic)
However, what does it mean to be a patient with DID? Emma Young wrote an article on dissociative identity disorder, exploring the experiences of Melanie. She had multiple personalities, which were described to be 'dissociated' from one another. In the first sense, the identities seem to be totally detached. There is inter-identity amnesia, meaning that one, when in one specific personality state, cannot recall what he/she has done when taken charge of by another personality state. In a study published on Psychological Medicine Journal [10], 22 patients with DID were tested on a series of multiple-choice questions in assessment of their memory recall capabilities. The patient subgroup was compared with a normal control group, where the participants were simulating to have multiple personalities. The results showed that the patient subgroup behaved differently to the normal control. Patients with DID, as they switched personality states, used new ways to tackle problems, as deduced from the fact that they exhibited different patterns of choosing incorrect answers. They were actively using their cognitive faculties, instead of pretending to have multiple personality states. In addition to affirming that DID is a genuine disorder, the study also confirmed inter-identity amnesia, whereby different personalities believed them to have different memory capabilities. Such beliefs deviated from actualities.
In the second sense, it could mean that the patient was entirely dissociated from one's experiences. Parallels could be struck between DID and a similar group of conditions, called derealisation and depersonalisation. In depersonalisation, one feels as if one is an observer of one's life, rather than an active participant. [11] In dissociation, it seems that everything can only be felt superficially, rather than deeply. This is problematic when it comes to romantic relationships, since there is no fundamental attachment between the two individuals. According to the trauma model, DID is a disorder emanating from the deep-grounded effects of dissociation, the ultimate, adaptive mechanism to protect the individual from undue harm. Dissociation does not only occur during the trauma. It persists and doesn't let the patient off the hook easily.
In the third sense, it can mean, quite literally, that a coherent personality is fragmented into different parts. The process of dissociation has been taken to extremes. One personality takes charge of the trauma and represents the state of the patient when dealing with it. One personality takes charge of the moment the trauma ended, and so forth. Taking Split as an example, Hedwig, the little boy, could represent the time before all the trauma occurred. It represented the naive little child Kevin once was. Dennis, one describable as overly meticulous, edging on compulsive tendencies, could represent the Kevin after enduring the trauma. Such meticulousness to detail can be traced back to the need to perfect one's behaviour so as to avoid triggers to his parent's use of force. One detail amiss and the trauma starts. In Young's article, Melanie has a three year-old self, a mature and functioning adult personality that is reflective of herself, a defiant teenage personality and a sage elderly personality. In the study on murderers with DID [3], nine subjects out of the twelve studied had violent male personalities which purported to have 'taken the pain' and six male subjects had older female personalities who were for 'caretaking, comforting and protecting'. This is why DID is no longer called 'multiple personality disorder'. These personalities are not just made up. They don't come out of the blue. They originate from the fragmentation of the self. Barriers are erected between them and a coherent self cannot be generated. This does not imply that different personality states cannot interact with each other. They can and their conversations or arguments contribute to auditory hallucinations and headaches, as determined through psychiatric evaluation. [3] It is simply that they interact as self-containing personas, rather than interdependent entities.
Diagram showing the Standard Model of Systems Consolidation, which exhibit the changes in memory storage in the brain. At first, memories are formed in virtue of connections made between the hippocampus and neocortex. As time passes, memories are solidified by the formation of connections between different parts of the neocortex. (Courtesy of Wikipedia)
In terms of treatment, there is not much available for patients with DID. However, psychotherapy is useful in removing the barriers between different personalities. The key to treatment is to reduce the distress experienced by patients and improve their symptoms. One way of doing so is to introduce reintegration. [12] This is not a magical process. Indeed, in Melanie's case, she experienced gross problems in performing rudimentary tasks upon receiving psychotherapy. [1] However, through time, one can live with multiple personality states and be comfortable with this arrangement. No medication currently helps with this condition, unless you're referring to symptomatic relief. For auditory hallucinations and other manifestations of psychosis, anti-psychotics and mood stabilisers (like lithium carbonate) can be used. There is also a technique called Eye Movement Desensitisation and Reprogramming (EMDR) which helps with the processing of traumatic memories. It alters the way the traumatic memory is stored in the brain and renders it in a manner which does not impact the patient too much. [13] In other words, it takes the 'fangs' away from the cobra. However, originally designed for PTSD, I doubt it will work effectively in DID, considering the immense amount of trauma experienced by such patients. The therapy may have to be modified so as to modify 'themes' of traumatic memories rather than 'specific memories', bearing in mind that patients with DID can simultaneously endure routine bouts of mutilation, beatings and sexual assault.
But then, can we dismiss all of this as a purely pathological issue? Do normal people also experience multiple personalities? We may think we are one coherent self all the time and nothing has changed. But then, looking back, even I concede that I changed a lot. From a playful and jolly boy who pretends to be Harry Potter by waving a chopstick cheekily in the air, to a geek who writes articles and reads the latest medical research for fun. Aren't we all our own dopplegangers, quoting How I Met Your Mother? These versions of ourselves, looking the same but differing in essence, walking down the street. The only difference we can draw between our metamorphosis and that of patients with DID is that, for the latter, they've gone to overdrive. Environmental conditions have been too traumatic so as to induce drastic modifications to their personality. For us, we simply get morphed gradually into different forms as our environments change. Funnily enough, we see our past selves and have no problem telling ourselves that, yes, that innocent child who hops on his scooter all the time is still us. Yet, we can no longer relate to him. That boy is merely a personality of his own, tucked away in the shadows of our mind.
References and Further Reading:
[1] Young E. My many selves: how I learned to live with multiple personalities. Mosaic Science. https://mosaicscience.com/story/my-many-selves-multiple-personalities-dissociative-identity-disorder/. Published 2017. Accessed December 13, 2020. (I've put this as the first reference since it gave me the inspiration to write this article. It's also the first popular medicine article I've read since a very important incident that happened to me last year)
[2] Reinders A, Veltman D. Dissociative identity disorder: out of the shadows at last?. The British Journal of Psychiatry. 2020:1-2. doi:10.1192/bjp.2020.168.
[3] Lewis DO, Yeager CA, Swica Y, Pincus JH, Lewis M. Objective Documentation of Child Abuse and Dissociation in 12 Murderers with Dissociative Identity Disorder. American Journal of Psychiatry. 1997; 154:12.
[4] Brand B, Loewenstein R, Lanius R. Dissociative Identity Disorder. Gabbard’s Treatments of Psychiatric Disorders. 2014. doi:10.1176/appi.books.9781585625048.gg24.
[5] Diagnostic And Statistical Manual Of Mental Disorders. Arlington, VA: American Psychiatric Association; 2017.
[6] O'Sullivan S. It's All In Your Head. 1st ed. London: Vintage; 2015.
[7] Chalavi S, Vissla EM, Giesen ME, et al. Abnormal hippocampal morphology in dissociative identity disorder and post-traumatic stress disorder correlates with childhood trauma and dissociative symptoms. Human Brain Mapping 2015; 36: 1692-704.
[8] Vermetten E, Schmahl C, Lindner S, Loewenstein RJ, Bremner JD. Hippocampal and amygdalar volumes in dissociative identity disorder. Am J Psychiatry. 2006;163(4):630-636. doi:10.1176/ajp.2006.163.4.630.
[9] Reinders A. Cross-examining dissociative identity disorder: Neuroimaging and etiology on trial. Neurocase. 2008;14(1):44-53. doi:10.1080/13554790801992768.
[10] Huntjens RJ, Peters ML, Woertman L, Bovenschen LM, Martin RC, Postma A. Inter-identity amnesia in dissociative identity disorder: a simulated memory impairment?. Psychol Med. 2006;36(6):857-863. doi:10.1017/S0033291706007100.
[11] Ewens H. I was terrified when my mind detached from my body – this is depersonalisation. The Guardian. https://www.theguardian.com/commentisfree/2015/dec/29/depersonalisation-lost-my-body. Published 2015. Accessed December 13, 2020.
[12] What Are Dissociative Disorders?. American Psychiatric Association. https://www.psychiatry.org/patients-families/dissociative-disorders/what-are-dissociative-disorders. Published 2020. Accessed December 13, 2020.
[13] Eye Movement Desensitization and Reprocessing (EMDR) Therapy. American Psychological Association. https://www.apa.org/ptsd-guideline/treatments/eye-movement-reprocessing. Published 2020. Accessed December 13, 2020.