Theory of Structural Dissociation

**Structural Dissociation** is a medical model linking trauma, dissociation, and separations in the personality. It comes in three levels: primary, secondary, and tertiary, each characterized by different disorders and different levels of dissociation. It’s essentially a synthesis of earlier models, in which the authors connect existing dots into one grand theory.

According to this theory, all individuals are born and live their early childhood in fragments. Humans do not develop a solid personality until mid-childhood; until then, simple desires, attachments to others, and impulses function independently. Six to nine years old is a common estimate as to when an individual’s personality begins to integrate or combine into a well-rounded one, but there is no solid research or proof on that window. If trauma occurs before this age, the integration can be interrupted, causing different pieces of the personality to be independent of each other. They can be as similar as slightly different mental states or emotions, or as different as any two individuals walking around today.

## Tiers

### Primary

Primary Structural Dissociation is commonly seen in PTSD, and consists of one traumatized part (also known as an Emotional Part or EP) and a part focused on daily living, called an Apparently Normal Part or ANP. Primarily dissociated individuals rarely refer to themselves as plural or as a system, as their two “sides” are often extremely similar and have no amnesia between them. The ANP is often avoidant of the EP and any reference to the trauma, while the EP is typically still living through the trauma.

### Secondary

Secondary Structural Dissociation is associated with BPD, Complex PTSD, and some cases of Other Specified Dissociative Disorder. There is usually one ANP with multiple EPs, each holding a different kind of trauma response or reaction. For example, there might be an EP for each of the four F’s (flight, fight, fawn, and freeze). Although BPD is not a dissociative disorder by classification, patients with it and/or C-PTSD may identify as median systems, as they are more differentiated than a singlet but less so than a DID system.

Other Specified Dissociative Disorder comes in many forms, so some subsets (notably OSDD-1a and -1b) may resemble a tertiary model, while other subsets (like OSDD-2 might fit under the secondary model.

### Tertiary

Tertiary Structural Dissociation is the most severe form listed, and is most common in Dissociative Identity Disorder systems. There are typically multiple ANPs and multiple EPs. At this point, the idea of these entities being simply “parts” starts to crumble, as many of them have separate names, ages, preferences, species, goals, and personalities. The divides between them often go deep, usually containing amnesia too.

Tertiary ANPs may hold different parts of daily life; academic headmates, work headmates, etc., just as EPs hold different parts of trauma.

## History

Structural dissociation was laid out comprehensively in a book called The Haunted Self by three authors: Ellert Nijenhuis, Onno van der Hart, and Kathy Steele — all three are experts in trauma-related dissociation. It may have been a proposal, but the groundwork has long since existed; The Haunted Self merely brought together decades of research.

Charles Samual Myers coined ANPs and EPs in response to working with shell-shocked WWI soldiers in the 1910s, and was a pioneer in the field; he was the first to introduce “shell-shocked” into medical publication and advocated for the healing for these soldiers and not writing them off. Structural dissociation also incorporates the work of Frank W. Putnam, one of the leading experts on plurality and literally wrote the book on how to treat DID in the 1980s. His work focused on the inherent fluidity of the personality and the biological, sociological, and developmental results of childhood abuse.

The Haunted Self was published in 2006 and immediately became an important guide in treating dissociative disorders, due to the legacy of both its authors & the sources they pulled from and its cohesiveness.

## Issues With The Theory Regarding Plurality

A prominent issue is that the ideas of ANPs and EPs were only meant to apply in cases of PTSD, not plurality. The creation of those labels were sourced in PTSD, so its application to disorders like BPD & DID is questionable (it also does not include depersonalization & derealization, despite being dissociative disorders). Further, many plurals (including median systems) find the use of “part” dehumanizing. Instead of recognizing headmates as different people, this model boils them down to simply dissociated parts of a cohesive personality.

Lastly, and probably the most well known, is the subject of integration & fusion. Since the beginning of medically recognized plurality, doctors & therapists have pressured systems into becoming singular, as they see it as the only way a system can be functional. This is expanded upon in structural dissociation by assuming that members of a system aren’t really different people, just segments, which highlights the importance of Final Fusion in the work. Although this is true of some systems (and they deserve respect too), many are content with their multiplicity, and have no interest in fusing into a singular individual. They may also instead instead prefer natural fusions to occur while still remaining plural, while others want to focus on other aspects of integration like bettering communication. In the modern day, resolution is also seen as a valid path for disordered systems.

Non-dissociative systems, systems not caused by trauma, spiritual systems, and other types of systems may struggle to find a place within the model.

## Related Terms

Fusion, integration, Apparently Normal Parts, and Emotional Parts are all integral to the function of this theory. Additionally, the idea of a core or original is sometimes seen as incongruous with Structural Dissociation as it proposes that there’s not a personality that splits, but a collection of parts that remain independent; however, this is untrue. Cores can and do exist within the framework of the theory, as explained here.

## Further Reading

* **Trauma-related Structural Dissociation of the Personality:** A summary of the full The Haunted Self book including excerpts. It is a very dense read but a good starting point.
* **Why The Theory Of Structural Dissociation is Ableist:** An opinion piece hosted by Power To The Plurals, a pro-endogenic site. It includes some excerpts from The Haunted Self.
* **Problems With The Theory of Structural Dissociation:** This article goes into the more nuanced reasons as to where the theory struggles with other dissociative disorders, and is less of a dry read than other pieces on the topic.
* **How Are New Alters Formed? An Explanation Of Structural Dissociation:** Although made by a sysmed, this video offers a good overview of the theory using visual aids and in a more consumable way.
* **Deconstruction structural dissociation:** A (admittedly very critical) book review of The Haunted Self and its flaws.