The Context-Dependency Model: A Model of Memory Functioning in Dissociative Identity Disorder

The phenomenology of dissociative identity disorder (DID) is controversial, with debates centred on whether multiple identities or personalities with independent memory streams and first-person experiences can coexist within a single individual. This thesis investigates whether these independent memory streams can align with the basic principles of memory. Specifically, we propose that findings of inter-identity amnesia in DID—characterized by impaired autobiographical recall but intact recognition and semantic memory across identity states—reflect the same patterns seen in context-dependent memory research. As such, if the switches between identities in DID represent abrupt and distinct changes in internal contexts, then the same principles of context-dependent memory may underly inter-identity amnesia in DID. To examine this, we implemented the reconstructive theory of self (RTS; Reichle & Boag, 2024), a computational memory model that is an extension of MINERVA 2 (Hintzman, 1984), which is known for simulating recall, recognition, and semantic memory, by accommodating longer-term representations of the autobiographical self. A series of simulations demonstrate that the present model can support explanations for (1) impaired autobiographical recall and intact recognition across identities in DID and (2) the existence of more than two distinct identities. Further simulations were conducted on semantic memory transfer and one-way versus two-way amnesic barriers in DID. Although the latter simulations were unsuccessful, these results offer preliminary support for a context-dependent account of memory compartmentalisation in DID. However, further refinement is necessary for this model to account for the full range of memory phenomena associated with DID. As such, the theoretical implications of the present model are discussed.