My thesis is about identity fragmentation in Dissociative Identity Disorder. Even before starting the thesis, I knew I wanted to do research involving dissociative disorders or trauma-related disorders. I had previously worked with Rafaele Huntjens in my research internship, and she suggested working on one of her projects for my master’s thesis. I began to read up on it and quickly realized that this would be a very interesting thesis topic. Focusing on the concept of identity is, in itself, a very engaging endeavour.  It is such a vast topic. How do you define someone’s identity? How is it related to mental health disorders involving difficulties understanding oneself or disorders involving trauma? Ultimately, this project offered me the opportunity to investigate these questions and also gave me the chance to work with actual patient data. 

Dissociative identity disorder (DID), formerly known as multiple identity disorder, is one of the most controversial disorders in DSM-5. People living with DID report having multiple identities within themselves, who are largely unaware of each other and who report having different names, ages, and preferences. Theories differ on how and why people with DID develop multiple identities. One theory assumes that identity fragmentation is a result of severe and repeated childhood abuse. Persons with DID, according to this theory, develop dissociated/fragmented parts of themselves as a way to deal with these experiences. The other theory holds that DID is not a direct consequence of childhood trauma, but instead of social learning and cultural expectancies in adulthood. Specifically, those with DID are said to develop the idea that they have multiple identities through, for example, the influence of therapy and media depictions of the disorder. Thus, the two theories fundamentally differ on how they conceptualize the identity fragmentation in DID.

The disorder is quite severe. Imagine: on average patients have 12 identities! Suicide rates are high, treatment takes very long and there is doubt about whether the current treatment approaches are as effective as they could be. Thus, it is not only important to better understand identity fragmentation in DID for advancing the theoretical debate on the disorder, but also for the innovation of treatment. 

The research
Our research project involved three groups: people with DID, people with schizophrenia, and non-clinical participants recruited from the community. Including the schizophrenia group was relevant, as DID shares some overlap in symptoms with this disorder. Both disorders are characterized by identity confusion and other dissociative symptoms. However, only DID is marked by identity fragmentation. We were therefore not only interested in what distinguishes DID and non-clinical people, but also people with DID and those with schizophrenia.

Due to the rarity of the disorder, it is quite challenging to recruit DID patients. We worked together with researchers from the University of Canterbury, New Zealand, for the recruitment process. They conducted the study with patients recruited from hospitals that had a specific programme dedicated to treating DID. DID patients needed to be stable enough to participate in the research and were asked to perform the task and questionnaire in an overview identity, meaning an identity that is more or less aware of the other identities.

Self-report and objective measures
Participants completed a card sorting task and a questionnaire on self-concept clarity. The card sorting task was set up to find out how people rate different aspects of themselves. Participants were asked to name different self-aspects (e.g., teacher, student, mother, friend) and to assign adjectives to these self-aspects (e.g., intelligent, insecure). As an example, you could have named ‘mother’ as one self-aspect of yourself with the adjectives ‘caring’ and ‘irritable’. The given adjectives could be reused across all the self-aspects.

The card-sorting task is a more objective measure of identity than self-report questionnaires. It was originally designed in the 1980s, and open-source, it evolved a lot. Over the years different indexes were added (and still are). We calculated four indexes. At the core was self-complexity: Do you identify with a few or many different ‘roles’? Naming a lot of self-aspects and characterizing these with different adjectives means a high score on self-complexity. Another index was compartmentalization: Do you see yourself as a mix of positive and negative characteristics all the time, or is it more fragmented? The negative attributes index shows how negatively people view themselves. Participants also rated the importance of the different self-aspects in their lives and how positive or negative they viewed them. That gave the data for the index differential importance: Do individuals put more importance on negative or on positive self-aspects?

The self-concept clarity scale is a self-report questionnaire used to assess the extent to which someone’s self-concept is clearly and confidently defined and how internally consistent and stable it is. Basically, it gives a more subjective and holistic measure of someone’s self-concept. These indexes can offer us interesting insights into differential self-concepts between the three groups.

Data can be tricky and rewarding 
I found doing this research project really interesting, even though analyzing the data of the card-sorting task was a bit frustrating at times. I really enjoyed that I also learned how to program the function for the calculations. As the sources were very old, it was sometimes tricky to get full and transparent insights into the original calculations. At times they were very technical and luckily, I had help from Mark Span from the DataLab at the University, who helped me towork out reliable calculations. The indexes themselves are very complex, so we had to put a lot of thought into getting it right. We are confident that with our script the indexes actually measure what we want them to measure, and hopefully, the Rscript we are currently writing is a useful source for future projects. We aim to publish the Rscript so that people are able to use the calculations for their research projects.

What I learned
This experience prepared me for future projects, where you think you know how it will go, and then it turns out that you don’t. I was expecting the calculation of the indexes to be technical, but not that it would be so complex and that it would take so long. I also learned more about programming than I ever did before. Ultimately, this project taught me a lot about communication and planning as many different groups and people were involved. I had to schedule meetings with people in a different time zone, review the indexes with the programmer, and make sure that my supervisor and the rest of the team was also informed about the progress and changes in the project. 

Results and follow-ups
Even though I finished my master's thesis, I am still further analyzing the data in light of other indexes that can be calculated for the card-sorting task. I am very keen to finish the analysis and hopefully publish the results soon. In September of this year, I also started my PhD project at the RuG, which further deals with identity fragmentation in DID. By relying on more objective cognitive tasks in DID, we aim to provide insights into inter-identity functioning that is not solely based on self-report data. I hope that I will be able to conduct my research as planned despite the pandemic. As DID is a very rare disorder, data collection and participant recruitment could prove to be difficult and will involve a lot of effort and travel. Nevertheless, I am looking forward to it.

Research or practice: a yearly debate
Regarding my future career, I am not sure if I will stay in academia after my PhD. It is a bit of a yearly debate: do I stay, or do I go? I absolutely enjoy working as a researcher, but I am also drawn to clinical practice. It is sometimes difficult to apply research findings to daily clinical practice and treatment and I would find it very rewarding if I would feel more experienced in being able to point out: This is what helps in a practical sense. So far, it is difficult to say what the future will hold but I am confident that I am well-prepared and able to walk whichever career path I end up choosing.