Studies investigating the structure of the amygdala in relation to dissociation in psychiatric disorders are limited and have reported normal or preserved, increased or decreased global volumes. Thus, a more detailed investigation of the amygdala is warranted. Amygdala global and subregional volumes were compared between individuals with dissociative identity disorder (DID: n = 32) and healthy controls (n = 42). Analyses of covariance did not show volumetric differences between the DID and control groups. Although several unknowns make it challenging to interpret our findings, we propose that the finding of normal amygdala volume is a genuine finding because other studies using this data-set have presented robust morphological aberrations in relation to the diagnosis of DID.

Dissociative identity disorder (DID) is a severely debilitating disorder. Despite recognition in the current and past versions of the DSM, DID remains a controversial psychiatric disorder, which hampers its diagnosis and treatment. Neurobiological evidence regarding the aetiology of DID supports clinical observations that it is a severe form of post-traumatic stress disorder.

The severe dissociative disorders of dissociative identity disorder (DID) and dissociative disorder not otherwise specified (DDNOS) are complex, not uncommon presentations associated with severe symptoms, high rates of comorbidity, high service use compared with other psychiatric disorders, and high suicidality. They exact high personal and socioeconomic burdens and show poor response to standard treatments, with high levels of treatment attrition and ‘revolving-door’ out-patient and in-patient service use; patients are often misdiagnosed or labelled ‘untreatable’. DID and DDNOS diagnoses remain controversial, but they have been repeatedly validated internationally over the past 20 years and the disorders can be accurately identified using screening tools and structured clinical interviews. Neurobiological understanding of the disorders is increasing; findings are consistent with a trauma origin and have commonality with features seen in other trauma-related disorders. Specialist treatment that addresses the dissociative symptoms alongside their trauma origins shows promise in early evidence. Working knowledge of these disorders among non-specialist psychiatrists and psychologists in the UK remains poor, resulting in long delays before diagnosis and treatment.

The aim of this review was to ascertain whether an examination of the theory of structural dissociation of the personality (TSDP) and its treatment may lead to recommendations in the treatment of dissociative identity disorder (DID) and other trauma-related disorders utilizing CBT. An analysis of the neurobiology of trauma will aid this process. The literature review considers a variety of literature on TSDP. Several themes were identified which suggested that dissociation refers to a structural dividedness of the personality and that there is a psychobiological pathway for all trauma-related disorders. Additionally the role of bottom-up vs. top-down processing was explored. Recommendations for the treatment of trauma-related disorders using CBT have been made.