Dissociation and Dissociative Identity Disorder: reframing trauma-related presentations

Dissociation is frequently encountered across medical and psychiatric settings, including general practice, emergency departments, and inpatient services, yet remains under-recognised outside specialist trauma contexts. This has direct implications for differential diagnosis, risk assessment, and treatment planning, particularly for patients presenting with recurrent crises, unexplained somatic symptoms, or persistent, treatment-resistant distress. 

Dissociation is best understood as a continuum, ranging from transient alterations in awareness to structurally organised dissociation following early and chronic trauma. It is a transdiagnostic psychobiological response involving disruptions in consciousness, memory, perception, and sense of self. Presentations may include amnesia, depersonalisation, derealisation, identity disturbance, somatic symptoms, and fluctuating mental states that do not align neatly with traditional diagnostic categories. 

Importantly, dissociation is not solely cognitive; it reflects altered integration across affective, autonomic, and somatic systems. Neurobiological and neuroimaging research demonstrates disrupted connectivity across large-scale brain networks involved in self-representation, threat detection, and emotional regulation, including the default mode, salience, and central executive networks. These findings support understanding dissociation as a disorder of integration across brain systems rather than a purely psychological phenomenon.

What does disassociation look like?

Dissociation functions as an adaptive response to overwhelming threat, particularly in the context of early developmental trauma and disrupted caregiving relationships. At lower levels, it may involve transient detachment or absorption; at higher levels, it may become persistent and structural, affecting memory integration, emotional regulation, and identity continuity. Severe dissociation is associated with earlier trauma onset, greater trauma severity, increased psychiatric comorbidity, suicidality, and functional impairment. 

Neurobiological models indicate altered coordination between limbic threat systems, including the amygdala, and prefrontal regulatory regions. These adaptations reflect survival responses rather than primary psychotic or degenerative pathology, but may become clinically impairing when persistent beyond the context in which they were adaptive.

Patients with significant dissociation often present with complex and fluctuating clinical pictures, including episodic amnesia, affect dysregulation, somatic complaints, self-harm, suicidality, substance use, and recurrent crises. These require careful differentiation from primary psychotic, mood, neurological, or personality disorders, as management pathways differ substantially.

A critical diagnostic distinction lies in the preservation of reality testing. Individuals with dissociative conditions, including Dissociative Identity Disorder (DID), typically experience internal voices or identity-related phenomena as internally generated, even when intrusive or distressing. This contrasts with primary psychotic disorders, in which symptoms are experienced as externally generated and accompanied by impaired reality testing. Recognition of this distinction is essential for accurate diagnosis and risk formulation. 

Misattribution of dissociative symptoms is common and may lead to inappropriate pharmacological treatment, fragmented care, and increased risk. Treatment approaches that do not account for dissociation — particularly rapid or unsupported trauma processing — may exacerbate dysregulation, shame, and suicidality. Limited training in dissociation contributes to under-recognition, delayed diagnosis, and increased healthcare utilisation. 

When dissociation becomes persistent and functionally impairing, it may meet criteria for a dissociative disorder, including depersonalisation/derealisation disorder, dissociative amnesia, other specified dissociative disorders, or DID. These conditions exist along a spectrum, differing in complexity and degree of identity disruption.

Dissociative identity disorder 

DID represents the most complex end of this spectrum. Although historically controversial and often misrepresented, it is formally recognised in DSM-5-TR and ICD-11 and is estimated to affect approximately 1–1.5% of the population. Epidemiological studies indicate that dissociative disorders are more prevalent in clinical populations than previously recognised, particularly among individuals with histories of early and chronic trauma. 

Contemporary models conceptualise DID as disrupted integration of identity rather than the presence of multiple personalities. Dissociated self-states develop in response to trauma occurring prior to consolidation of a cohesive sense of self and may serve distinct affective, defensive, or relational functions, resulting in discontinuities in memory, affect, and identity. 

Recent research has strengthened the evidence base for phased, stabilisation-focused treatment. A 2025 international randomised controlled trial evaluating Finding Solid Ground (FSG), an online psychoeducational intervention for trauma-related dissociation, demonstrated significant improvements in emotion regulation, PTSD symptoms, self-compassion, and adaptive functioning, with sustained effects at 12 months.

These findings support stabilisation as a core therapeutic phase rather than merely preparatory. Stabilisation involves developing self-regulation, reducing high-risk behaviours, and strengthening adaptive functioning prior to trauma processing. The trial authors caution against rapid or intensive trauma-focused interventions without adequate stabilisation in highly dissociative populations, due to increased risk of destabilisation, self-harm, and treatment dropout. 

This does not argue against trauma-focused therapy, but emphasises the importance of timing, pacing, and readiness. Phased models of care are increasingly supported as the safest and most effective approach for individuals with complex trauma-related dissociation.

The need for trauma-informed care

For medical practitioners, priorities include recognising dissociation as a trauma-related response, differentiating it from primary psychiatric and neurological conditions, assessing safety and risk, and facilitating referral to trauma-informed services capable of providing stabilisation-focused care. Establishing precise dissociative subtypes is less urgent than ensuring safe initial management.

For health systems, this highlights the need for improved clinician education, stabilisation-first models of care, access to structured psychoeducation, and governance frameworks capable of supporting high-acuity populations. Failure to recognise dissociation contributes to repeated crises, diagnostic cycling, polypharmacy, and escalating risk responses that do not address underlying trauma processes. 

Dissociation is a common and clinically significant trauma response spanning diagnostic categories and healthcare settings. DID represents the most complex manifestation of this process rather than a discrete or anomalous condition. Reframing dissociation within a trauma-informed, neurobiologically grounded framework reduces stigma, improves diagnostic accuracy, and supports safer, more effective care.

The critical question for contemporary medical practice is not whether dissociation should be taken seriously, but whether health systems are equipped to recognise it early and respond in ways that are safe, evidence-informed, and trauma-responsive.

Dr Cathy Kezelman AM trained as a medical practitioner, is President of Blue Knot Foundation, Chair of National Centre for Action on Child Sexual Abuse and has a lived and living experience of complex trauma.