The severity of dissociation and dissociative phenomena in non-affective psychosis: a systematic review and meta-analyses

Co-occurrence of dissociation and anxiety and depressive disorders in adults: a scoping review

Background Dissociation, including depersonalization, derealization, dissociative identity disorder or dissociation in the context of functional neurological disorder, is classically associated with trauma-related disorders but is increasingly reported in anxiety and depressive disorders. Despite growing evidence linking dissociation to affective symptom severity, functional impairment, and treatment outcomes, its role in anxiety and depression remains insufficiently synthesized. Objective This scoping review aimed to map the extent, nature, and characteristics of dissociation in adults with anxiety and depressive symptoms, with a focus on conceptualization, assessment methods, prevalence, and clinical correlates. Methods Using Joanna Briggs Institute methodology and PRISMA-ScR guidelines, PubMed and Scopus were searched from inception to January 2025. Studies assessing dissociation in adults with anxiety and/or depressive symptoms using validated instruments or clinical interviews were included. Data were charted and synthesized thematically. Results A total of 300 studies were included. Of these, 49 studies focused on depersonalization–derealization phenomena, 11 studies examined dissociative identity disorder or complex dissociative disorders, 139 studies investigated functional neurological disorders, and 101 studies addressed mixed or transdiagnostic dissociative phenomena. Across anxiety and depressive disorders, dissociative symptoms were common and dimensionally distributed across clinical samples, with severity varying by diagnosis, setting, and assessment method. In depersonalization-focused studies, approximately 41-43% of patients met criteria for at least one anxiety disorder, and comorbid depression was reported in 62% to 84.8% of clinical series. In functional neurological disorder populations, dissociative symptoms- most commonly assessed with the DES- were elevated in approximately 30–60% of patients and were strongly associated with comorbid anxiety and depression. In FND sample, anxiety and depressive symptoms were highly prevalent, affecting approximately one-third to two-thirds of patients. Across diagnostic categories, higher dissociation was consistently associated with greater symptom severity, increased functional impairment, higher rates of suicidality, and poorer treatment outcomes. Conclusions This scoping review demonstrates that dissociation is a frequent and clinically relevant feature of anxiety and depressive disorders, extending beyond traditional dissociative diagnoses and intersecting with functional neurological symptoms. The findings support transdiagnostic and dimensional models of psychopathology, in which dissociation reflects stress-related disturbances in self-experience and emotional processing. Routine assessment of dissociative symptoms in anxiety and depression may enhance clinical characterization and inform more targeted interventions. Future research should prioritize longitudinal and mechanistic studies to clarify causal pathways and treatment implications. Systematic Review Registration https://osf.io/hnjpb/, identifier hnjpb.

How psychosis shapes the impact of childhood trauma on social cognition in bipolar disorder: the role of Theory of Mind.

OBJECTIVE Childhood trauma and psychotic symptoms are prevalent in bipolar disorder (BD) and independently linked to social cognition impairments, particularly Theory of Mind (ToM). However, it remains unclear whether trauma and psychosis exert cumulative effects on ToM performance in BD. METHODS We conducted a cross-sectional study involving 54 euthymic individuals with BD reporting at least moderate childhood trauma (Childhood Trauma Questionnaire; CTQ). Participants completed the Reading the Mind in the Eyes Test (RMET) to assess ToM. Clinical and sociodemographic data were collected. Participants were stratified by lifetime psychotic symptoms for between-group comparisons. RESULTS Individuals with a history of psychotic symptoms (n=18) reported significantly higher total CTQ scores (Mean=61.0, SD=15.7) than those without psychotic symptoms (Mean=44.5, SD=13.1; p=0.028) and exhibited significantly lower ToM accuracy (Mean RMET=23.0, SD=4.5 vs. 25.4, SD=3.4; p<0.001, d=0.58). CONCLUSIONS In BD, the co-occurrence of childhood trauma and lifetime psychosis is associated with more pronounced ToM deficits. These results highlight the need for trauma-informed approaches and early cognitive interventions targeting social cognition in individuals with BD and psychosis history.

[Treatment of dissociation in borderline personality disorder with dissociative identity disorder and complex post-traumatic stress disorder: A clinical case].

Clinical Evidence for Increased Dissociative Experiences in Adults with High Levels of Autistic Traits: A Comparative Study.

Autism spectrum disorder (ASD) is associated with a variety of mental health conditions, including dissociation. In addition to high rates of trauma exposure, vulnerability for dissociation in autism may be heightened by social differences, cognitive inflexibility, and sensory sensitivities. This study examined dissociative symptoms across levels of autistic traits using existing clinical data from 716 individuals receiving mental health care ("clients") in Australia. Clients completed the Multidimensional Inventory of Dissociation-60 (MID-60), the Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS-R), and the Adverse Childhood Experiences Questionnaire (ACE-Q) or Life Events Checklist for DSM-5 (LEC-5). Clients were grouped according to their RAADS-R scores, measuring autistic traits. Analyses first compared those with high autistic traits (HA; ≥120; n = 338) to below-threshold autistic traits (BA; <120; n = 378). The latter group was then subdivided into those with moderate autistic traits (MA; 65-119; n = 214) and low autistic traits (LA; <65; n = 164) for more comprehensive analysis. HA clients had the highest scores on all trauma and dissociation measures and subscales, and clinically elevated dissociation was significantly more prevalent among HA clients (68%) than BA clients (33%; OR = 4.42) and LA clients (15%; OR = 12.59). MA clients also scored higher than LA clients in almost all domains. Autistic traits and dissociation severity were significantly correlated overall and for all subscales, with the strongest correlations found for the RAADS-R Sensory-Motor domain. All relationships remained significant after controlling for ACEs. This highlights the need for routine screening and tailored interventions addressing both autistic traits and dissociation.

Revisiting the link between childhood adversity and stress-sensitive brain regions in psychosis and bipolar disorder: A systematic review and meta-analysis

CA was not consistently associated with hippocampal or amygdala volume alterations in PD and BD, and more consistent evidence emerged for reduced GMV in prefrontal regions, suggesting that neurobiological impact of CA may be more robustly captured at the cortical level.

Basic symptoms of psychosis-from historical foundations to current evidence.

PURPOSE Psychoses are among the most debilitating mental disorders, making early detection a major public health priority. In extension of the ultra-high-risk (UHR) approach, which was developed to identify an imminent risk of psychosis, the basic symptom (BS) approach aims for the earliest possible detection of the developing disorder; it is increasingly used worldwide. Basic symptoms are subtle, self-perceived disturbances affecting various domains, such as cognition, perception, affect, and drive, that precede and scaffold the development of attenuated and frank psychotic symptoms. METHODS AND RESULTS This narrative review outlines historical foundations, phenomenology, and assessment instruments for BSs. It summarizes empirical findings on their predictive value for subsequent psychosis and their specificity for psychotic disorders across all age groups. Furthermore, developmental aspects and neurobiological findings are highlighted that support one of the core assumptions of the BS concept, namely, that BSs represent the most immediate phenomenological manifestation of the cerebral alterations underlying the development of psychosis. Finally, evidence for the broader clinical significance of BSs beyond psychosis prediction is discussed, indicating that BSs as a whole are useful for both multi- and differential-diagnostic purposes. CONCLUSION Overall, the reviewed findings underline the value of BSs for advancing neurobiological research on the etiopathology of psychoses and for developing individualized prediction models and targeted early interventions.