Depersonalisation-derealisation disorder (DDD) is characterised by distressing experiences of separation from oneself and/or one\'s surroundings, potentially resulting from alterations in affective, cognitive, and physiological functions. This systematic review aimed to synthesise current experimental evidence of relevance to proposed mechanisms underlying DDD, to appraise existing theoretical models, and to inform future research and theoretical developments. Studies were included if they tested explicit hypotheses in DDD samples, with experimental manipulations of at least one independent variable, alongside behavioural, subjective, neurological, affective and/or physiological dependent variables. Some evidence for diminished subjective responsivity to aversive images and sounds, and hyperactivation in neurocircuits associated with emotional regulation when viewing aversive images emerged, corroborating neurobiological models of DDD. Inconsistencies were present regarding behavioural and autonomic responsivity to facial expressions, emotional memory, and self-referential processing. Common confounds included small sample sizes, medication, and comorbidities. Alterations in affective reactivity and regulation appear to be present in DDD; however, further research employing more rigorous research designs is required to provide stronger evidence for these possible mechanisms.

Pathological dissociation is relatively common in the United States and may be associated with violent or criminal behavior. Dissociative Disorders, especially Dissociative Identity Disorder, are considered controversial diagnoses by some in the psychiatric and legal professions. Individuals who offend during dissociative states may not be criminally responsible if they meet the legal standard for insanity, however, insanity pleas based on dissociative symptoms are rare. This review examined Federal appellate case law for potential legal barriers to the insanity defense for dissociative conditions and any restrictions imposed on related expert evidence. Few rulings directly addressed these questions but there do not appear to be any unique barriers for dissociation-related insanity pleas. Some cases provided valuable insights regarding the admission of expert evidence, effective expert testimony, and the role of defense counsel.

UNASSIGNED: Reduced memory specificity (i.e., overgeneral memory) is a characteristic of autobiographical memories widely studied in clinical populations, and it is explained by rumination, functional avoidance, and executive dysfunction. Though the relationship of autobiographical memory specificity with mood and anxiety disorders has been shown, how it relates to dissociation is not well-established. Thus, we aimed to investigate whether dissociative experiences are related to overgeneral memory while considering concurrent depression as a possible confounding factor.
UNASSIGNED: We conducted a systematic review in compliance with The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and searched PubMed and Web of Science databases using autobiograph* and dissoc* as our keywords.
UNASSIGNED: Of the 768 studies identified, 9 studies fulfilled the inclusion criteria. A meta-regression analysis was conducted to analyze the relationship between dissociative experiences and depression scores with autobiographical memory test scores. Our research revealed that depression scores, but not dissociative experiences, are significantly related to reduced memory specificity.
UNASSIGNED: While the possible overlap between dissociation and depression should be considered in the interpretation of the findings, dissociative experiences do not seem to pose vulnerability for reduced specificity of autobiographical memory. The number of studies on the topic is limited, and they do not have longitudinal follow-ups. The heterogeneous reporting of memory scores and low scores of dissociative experiences in the samples are also limitations of the existing studies.

BACKGROUND: Dissociation is a psychological process in reaction to threat which can be found in many psychiatric conditions. Dissociative symptoms can become very disabling, whether in daily life or in care. Nevertheless, few studies seem to have examined the efficacy of psychotherapy on the latter and its relevance as a therapeutic target.
METHODS: A systematic review of the literature (PRISMA) on the efficacy of psychotherapy on dissociative symptoms in adults with mental disorders was conducted. Effectiveness was considered in terms of reduction in dissociative symptomatology. The search was conducted on Scopus, PubMed and PsycInfo. Overall, 50 full-text articles were evaluated.
RESULTS: Fourteen studies were included in the review. In all, 711 adult subjects with post-traumatic stress disorder, borderline personality disorder or dissociative disorder were included. Overall, this systematic review reports a reduction in dissociative symptoms associated with a variety of psychotherapeutic interventions, without allowing any conclusions to be drawn on the superiority of one psychotherapy over another.
CONCLUSIONS: The conclusions of this work highlight three possible therapeutic orientations for reducing dissociative symptoms: (i) by reintegrating the dynamic subsystems, (ii) by treating the cognitive processes underlying dissociation, and (iii) by acting on the processes identified as common to the effectiveness of psychotherapy.

BACKGROUND: Dissociation is a feature of Borderline Personality Disorder (BPD), but rarely a focus for research, particularly in the perinatal literature. BPD partly has its aetiology in childhood and is characterised by emotional changes and difficulty with self-coherence that impacts on the processes of caregiving.
METHODS: A scoping review was conducted to synthesise current perspectives on the effect of dissociation in caregivers with BPD, particularly regarding the impact of caregiver dissociation on the interactional quality of relationship within parent-child dyads. Studies were included if they explicitly mentioned dissociation in the target population, or if dissociation was implied. A thematic analysis was conducted.
RESULTS: 20 studies were included; 10 experimental or quasi-experimental; 2 presenting case material; and 8 non-systematic review articles. 4 studies used the Dissociative Experiences Scale (DES) to measure dissociation, while 2 studies included a \'dissociative behaviour\' subscale as part of an observational measure. The remaining studies did not measure dissociation but referenced directly or indirectly a concept of dissociation.
CONCLUSIONS: Findings suggested there was some evidence that dissociation plays a unique role in BPD caregivers\' interactions with their offspring, however any findings should be interpreted with caution as the concept has been poorly operationalised and defined.

OBJECTIVE: Insecure attachment may constitute a vulnerability factor for psychosis, and dissociation may be a key mechanism in the development of auditory hallucinations specifically. While there is good evidence for the role of these processes in isolation, it is unclear whether dissociation accounts for the association between insecure attachment and psychosis. This systematic review takes a theory-driven approach to examine proposed causal relationships across the clinical and nonclinical literature.
METHODS: We searched five databases (PubMeD, Web of Science, PsycINFO, CINAHL and ETHOS) for published and unpublished research examining attachment, dissociation and psychosis. Two independent reviewers extracted the data and assessed the quality of all included studies.
RESULTS: We identified 242 potential articles and included 13 in the final review (2096 participants). We found that (1) disorganised attachment was consistently associated with dissociation and inconsistently associated with voices and paranoia, (2) dissociation was associated with voices and paranoia, and these links were stronger in clinical samples, and (3) dissociation played a role in the impact of insecure attachment on voice hearing and paranoia in clinical groups.
CONCLUSIONS: This is the first review to synthesise the research examining attachment, dissociation, and psychosis. The evidence is consistent with proposed causal hypotheses and raises conceptual and measurement issues, for example, the need to clarify the relative contributions of different insecure attachment styles, and utilise behavioural/observational measures to strengthen study designs. Most importantly, we need experimental and longitudinal studies to confirm causal links and targets for treatment.

The 11th revision of the International Classification of Diseases (ICD-11) introduced Complex Posttraumatic Stress Disorder (CPTSD) as a sibling disorder to PTSD. Dissociative symptoms have been implicated in the severity of ICD-11 CPTSD; however, no reviews have investigated how dissociation has been measured in studies investigating CPTSD, nor the relationship between CPTSD and dissociation. This systematic review aimed to identify measures used to assess dissociative symptoms in studies that have assessed CPTSD according to ICD-11 criteria and to synthesize the relationship between these constructs. PsycINFO, PubMed, Scopus and Web of Science were searched on March 31, 2021. Seventeen articles met inclusion criteria. CPTSD was most frequently measured by a version of the International Trauma Questionnaire. Twelve measures were used to assess for dissociative symptoms, the most common being the Dissociative Symptoms Scale and the Dissociative Experiences Scale. The relationship between CPTSD and dissociative symptoms was moderate-to-strong, but inconsistently reported. Further research is needed to determine the most appropriate measure(s) of dissociation in CPTSD.

Ketamine is a phencyclidine (PCP) derivative, which primarily acts as a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist. Ketamine serves as an analgesic and a dissociative sedative that produces potent analgesia, sedation, and amnesia while preserving spontaneous respiratory drive. It is rapidly gaining acceptance in the management of pain as multiple studies have demonstrated its reliable efficacy and a wide margin of safety. This article reviews some of these studies, the history of ketamine, and its pharmacological and pharmacokinetic properties. The article also discusses the use of ketamine in the trauma setting, including joint reductions, procedures, sedation, and pain control, as well as dosing recommendations.

The clinical guidelines for the treatment of dissociation focus primarily on psychotherapy. However, different psychoactive drugs are used in clinical practice. The use of opioid antagonists has been proposed as a therapeutic option based on the theory that dissociation might be a phenomenon mediated by dysregulation of the endogenous opioid system.
To review and meta-analyse the available evidence on the efficacy of the opioid antagonists naltrexone, naloxone, and nalmefene as treatments for dissociative symptoms and disorders.
The PRISMA guidelines were followed, and this review was registered in Prospero with reference number CRD42021280976. The search was performed in the PubMed, Scopus, Web of Science, EMBASE, PsycINFO, and PubPsych databases.
1,798 citations were obtained. After removing duplicates and applying inclusion and exclusion criteria, we included 5 comparative studies with 9 dissociation measures that had included a total of 154 participants, of whom 134 had been treated with an opioid antagonist. The results of the meta-analysis showed a treatment effect for dissociation when using opioid antagonists [pooled d = 1.46 (95% CI: 0.62-2.31)]. However, the studies we included were very heterogeneous [Q = 66.89 (p < .001)] and there may have been publication bias.
Although more research is needed and the results must be interpreted with caution because of the limited amount of data and heterogeneity in the studies and their methodological qualities, opioid antagonists (particularly naltrexone) are promising candidates for the treatment of dissociative symptoms and showed a moderate - large effect size in reducing these symptoms.
The results of the meta-analysis showed a treatment effect for dissociation when using opioid antagonists [pooled d = 1.46 (95% CI: 0.62–2.31)].The results must be interpreted with caution because of the limited amount of data and heterogeneity in the studies and their methodological qualities.Opioid antagonists (particularly naltrexone) are promising candidates for the treatment of dissociative symptoms and showed a moderate – large effect size in reducing these symptoms.

BACKGROUND: Dissociative identity disorder and depersonalization-derealization have attracted research and clinical interest, facilitating greater understanding. However, little is known about the experience of multiplicity of self outside of traumagenic or illness constructs. Consequently, this systematic review explored how people identifying as having multiple selves conceptualize their experiences and identity.
METHODS: A comprehensive search of qualitative studies reporting lived experiences of multiplicity was conducted through PsycINFO, PubMed and Scopus (PROSPERO ID: CRD42021258555). Thirteen relevant studies were retrieved (N = 98, 16-64 years, conducted in the United Kingdom, the United States, Hungary and Poland).
RESULTS: Using line-by-line thematic synthesis, four analytical themes were developed: multiplicity: disorder versus experience; impact of understanding multiplicity; importance of supporting multiplicity; and continuum of experiences.
CONCLUSIONS: This review highlights heterogeneity within multiplicity-spectrum experiences, emphasizing the need for person-centred, individualized understanding, separate from mental health conceptualizations. Therefore, training in person-centred individualized care to promote self-concept clarity is needed across health, education and social care. This systematic review is the first to synthesize voices of people with lived experience across the multiplicity spectrum, demonstrating how qualitative research can contribute to advancing our understanding of this complex phenomena with the community, acknowledging reciprocal psychosocial impacts of multiplicity and providing valuable recommendations for services.