Dissociation and its disorders: Competing models, future directions, and a way forward

Severe Dissociative Experiences beyond Detachment in a Large Clinical Sample of Inpatients with Post-Traumatic Stress Disorder: Diagnostic and Treatment Implications

INTRODUCTION

The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) contains a dissociative subtype of post-traumatic stress disorder (PTSD) characterized by depersonalization and derealization. Yet, there is evidence that dissociative symptoms in PTSD go beyond this kind of detachment dissociation and that some patients present with additional compartmentalization dissociation in the form of auditory-verbal hallucination, amnesia, and identity alteration.

METHODS

Hence, in this study, we examined latent profiles of childhood trauma (Childhood Trauma Questionnaire), PTSD (Impact-of-Event Scale-Revised), and pathological dissociation (Dissociative Experiences Scale-Taxon; DES-T) in a large sample of severely traumatized inpatients with PTSD (N = 1,360).

RESULTS

Results support a three-class solution of the latent profile analysis with a PTSD class, a dissociative subtype class, and a third class characterized by more complex and more severe dissociative symptoms. Importantly, in our inpatient sample of patients with severe PTSD, the latter class was found to be the most prevalent. Both the exploratory character of our retrospective analysis of clinical routine data and the use of the DES-T limit the generalizability of our findings, which require methodologically more rigorous replication.

CONCLUSION

In severe PTSD, dissociative symptoms beyond detachment are highly prevalent. Diagnostic and treatment implications are discussed.

Sleep and dream disturbances associated with dissociative experiences

Some dissociative experiences may be related, in part, to REM intrusion into waking consciousness. If so, some aspects of dream content may be associated with daytime dissociative experiences. We tested the hypothesis that some types of dream content would predict daytime dissociative symptomology. As part of a longitudinal study of the impact of dreams on everyday behavior we administered a battery of survey instruments to 219 volunteers. Assessments included the Dissociative Experiences Scale (DES), along with other measures known to be related to either REM intrusion effects or dissociative experiences. We also collected dream reports and sleep measures across a two-week period from a subgroup of the individuals in the baseline group. Of this subgroup we analyzed two different subsamples; 24 individuals with dream recall for at least half the nights in the two-week period; and 30 individuals who wore the DREEM Headband which captured measures of sleep architecture. In addition to using multiple regression analyses to quantify associations between DES and REM intrusion and dream content variables we used a split half procedure to create high vs low DES groups and then compared groups across all measures. Participants in the high DES group evidenced significantly greater nightmare distress scores, REM Behavior Disorder scores, paranormal beliefs, lucid dreams, and sleep onset times. Validated measures of dreamed first person perspective and overall dream coherence in a time series significantly predicted overall DES score accounting for 26% of the variance in dissociation. Dream phenomenology and coherence of the dreamed self significantly predicts dissociative symptomology as an individual trait. REM intrusion may be one source of dissociative experiences. Attempts to ameliorate dissociative symptoms or to treat nightmare distress should consider the stability of dream content as a viable indicator of dissociative tendencies.

Dissociative Symptoms and Interoceptive Integration

Dissociative symptoms and disorders of dissociation are characterised by disturbances in the experience of the self and the surrounding world, manifesting as a breakdown in the normal integration of consciousness, memory, identity, emotion, and perception. This paper aims to provide insights into dissociative symptoms from the perspective of interoception, the sense of the body's internal physiological state, adopting a transdiagnostic framework.Dissociative symptoms are associated with a blunting of autonomic reactivity and a reduction in interoceptive precision. In addition to the central function of interoception in homeostasis, afferent visceral signals and their neural and mental representation have been shown to shape emotional feeling states, support memory encoding, and contribute to self-representation. Changes in interoceptive processing and disrupted integration of interoceptive signals into wider cognition may contribute to detachment from the body and the world, blunted emotional experience, and altered subjective recall, as experienced by individuals who suffer from dissociation.A better understanding of the role of altered interoceptive integration across the symptom areas of dissociation could thus provide insights into the neurophysiological mechanisms underlying dissociative disorders. As new therapeutic approaches targeting interoceptive processing emerge, recognising the significance of interoceptive mechanisms in dissociation holds potential implications for future treatment targets.

Borderline personality disorder and sexuality: causes and consequences of dissociative symptoms

BACKGROUND

Sexual risk behavior in patients diagnosed with borderline personality disorder (BPD) is supposed to be associated with traumatic experiences and dissociative symptoms. Nevertheless, scientific research thereon is scarce which might be due to the high prevalence of sexual trauma and fear of overwhelming patients with explicit sexual content.

METHODS

We investigated a clinical sample of patients diagnosed with BPD (n = 114) and compared them to a sample of matched healthy controls (HC) (n = 114) concerning the dissociative symptoms derealization, depersonalization, and conversion in sexual situations. In a subgroup of patients with BPD (n = 41) and matched HC (n = 40) dissociative symptoms after exposure to an acoustically presented erotic narrative were assessed in the lab. Regression analyses were used to examine the associations between sexual trauma, post-traumatic stress disorder (PTSD), dissociation in sexual situations, and risky sexual behavior.

RESULTS

Patients diagnosed with BPD endorsed higher dissociative symptoms in sexual situations retrospectively and in the lab compared to HC. Regression analyses revealed that depersonalization and conversion symptoms in sexual situations were explained by severity of BPD, while derealization was explained by PTSD symptomatology. Impulsive and sexual behavior with an uncommitted partner were higher in the BPD group and explained by derealization, while conversion showed an inverse association.

CONCLUSION

Our findings highlight the importance of addressing distinct dissociative symptoms in sexual situations when counselling and treating women with BPD. In the long term, this could contribute to a reduction in sexual risk behavior in patients with BPD.

TRIAL REGISTRATION

This analysis is part of a larger ongoing study and was registered prior to accessing the data (Registration trial DRKS00029716).

Dissociation in mothers with borderline personality disorder: a possible mechanism for transmission of intergenerational trauma? A scoping review

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.

Dissociative Symptoms in Complex Posttraumatic Stress Disorder: A Systematic Review

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.

Dissociative Identity Disorder: A Review of Research From 2011 to 2021

ABSTRACT

Dissociative identity disorder (DID) has historically been one of the most controversial topics in the study of psychopathology. Building on a previous review of empirical research on DID from 2000 to 2010, the present review examined DID research from 2011 to 2021. The research output included 56 case studies and 104 empirical studies. Within the empirical studies, approximately 1354 new cases of DID emerged, which resulted in an average samples of approximately 20. Reanalysis of previous samples was standard in the literature with only 40% of reported cases being new. Studies emerged from dozens of countries across the world, but the majority of cases were from Western counties, especially the United States. Diagnosis primarily relied upon validated measures, but 74% of all new cases came from six research groups. Overall, research on DID is steady but methodologically limited in ways that make generalization, especially about etiology, difficult.

The association between dissociative symptoms and schizophrenia-related negative symptoms: A transdiagnostic approach

Negative symptoms of schizophrenia remain clinically and theoretically understudied and represent an unmet psychiatric need. Negative symptoms are assumed to be related to other psychiatric disorders, but their association with dissociative symptoms is yet to be explored, particularly in light of depression and anxiety symptoms. We examined the five domains of negative symptoms (anhedonia, asociality, avolition, blunted affect and alogia) in an Israeli national sample of 1930 participants of whom 645 (33.4%) were with increased risk for dissociative disorder. The results show that anhedonia, blunted affect and alogia significantly associated with risk for dissociative disorder, above and beyond depression and anxiety. When assessing for negative symptoms it may be worth screening for dissociation and vice versa and thus make a more accurate clinical picture of the interplay between them.

Cross-validation of the ego dissolution scale: implications for studying psychedelics

Introduction

Ego dissolution, variously called Ego-Loss, self-loss, and ego disintegration, is a hallmark of psychedelic drug use. We cross-validated the 10-item Ego Dissolution Scale, which we developed to assess ego dissolution in everyday life, and we included comparator variables that expanded our original assessment of construct validity.

Methods

Undergraduate college student volunteers (N = 527) completed the measures online.

Results

We replicated the original two factor structure (i.e., subfactors: Ego-Loss and Unity/connectedness with others, the world, universe), and we determined that the total score (Cronbach's α = 0.79) and subfactors (Ego-Loss = 78; Unity = 0.83) possessed adequate-to-good reliability and strong convergent validity (e.g., mindfulness, hallucination-predisposition, sleep variables, personality variables, positive/negative affect transliminality, dissociation/depersonalization), while neuroticism, social desirability did not correlate highly with ego dissolution. We identified distinct patterns of relations of measures associated with the Ego-Loss vs. Unity subfactors.

Discussion

We discuss the implications of the use of the EDS for studying everyday aspects of ego dissolution, the long-term effects of psychedelic use, and the value of using the scale in conjunction with measures of the acute effects of psychedelics.

Childhood experiences and dissociation among high school students in China: Theoretical reexamination and clinical implications

BACKGROUND

Dissociation remains a controversial topic in terms of its prevalence, cross-cultural validity, and relationship with childhood trauma and adversities.

AIMS

This study investigated the prevalence of dissociative symptoms and probable dissociative disorders among Chinese high school students and tested the trauma model of dissociation.

METHODS

A total of N = 1,720 high school students completed standardized measures of positive and adverse childhood experiences (PCEs and ACEs), dissociation, depression, and anxiety.

RESULTS

The prevalence rates of dissociative symptoms and (probable) DSM-5 dissociative disorders (DDs) were 11.2% and 6.9%, respectively. Dissociation was a reliable construct (ICC = .682 to .752, p < .001) and was moderately correlated with general psychopathology (r = .424 with depressive symptoms, r = .423 with anxiety symptoms). Participants with a probable DD reported more ACEs, fewer PCEs, and more mental health symptoms than those without a probable DD. ACEs were significantly associated with dissociative symptoms (β = .107, p < .001) even after controlling for age, depressive, and anxiety symptoms. PCEs moderated the relationship between ACEs and dissociative symptoms.

CONCLUSIONS

This is the first report of the prevalence of dissociative symptoms and probable DSM-5 DDs among nonclinical children. We provide cross-cultural evidence that dissociation is a reliable and valid clinical phenomenon associated with psychopathology in children across cultures. The findings partly support the trauma model of dissociation. This study contributes to the limited literature on dissociation in children. It also offers empirical data to facilitate the ongoing controversy about (childhood) trauma and dissociation. Our findings imply that dissociation is cross-culturally associated with childhood adversities, but trauma is not the only, sufficient cause. Theoretical and clinical implications are discussed.

Therapeutic Dance for the Healing of Sexual Trauma: A Systematic Review

Therapeutic dance has been increasingly used as a treatment modality for sexual trauma, yet its evidence-based efficacy has not yet been catalogued. We therefore conducted a systematic review to summarize the existing evidence for therapeutic dance as an intervention for healing after sexual trauma. We searched 5 major databases to identify intervention studies on the use of therapeutic dance for individuals with histories of sexual trauma. Studies were included based on the following criteria: 1) the study involves individuals who have been exposed to sexual trauma; 2) the study reports on any form of dance as a therapeutic intervention; and 3) the study reports on dance intervention outcomes. A total of 1,686 sources were identified. Of these, 11 articles met eligibility criteria and were assessed. Reported outcomes were extracted and organized into emergent domains. We found that therapeutic dance acts upon three broad domains-affect, self, and interpersonal relationships - and can be delivered in diverse settings. Across the studies, dance showed benefits on outcomes. However, a significant weakness of the current peer-reviewed literature is the lack of robust empirical intervention research on dance therapy. Overall, the emerging literature suggests that therapeutic dance is a potential intervention for those who have experienced sexual trauma. The review findings presented here can be used to inform practitioners and systems of care targeted for those who have been subject to sexual trauma.

The temporal dynamics of dissociation: protocol for an ecological momentary assessment and laboratory study in a transdiagnostic sample

BACKGROUND

Dissociation is a ubiquitous clinical phenomenon. Dissociative disorders (DD) are primarily characterized by dissociation, and dissociative states are also a criterion for borderline personality disorder (BPD) and the dissociative subtype of post-traumatic stress disorder (PTSD). Dissociative reactions (e.g., depersonalization/derealization or gaps in awareness/memory) across diagnostic categories are believed to be affect contingent and theorized to serve affect regulation functions. What is not clear, however, is how self-reported affect and physiological reactivity unfold within dissociative episodes. To address this issue, the present project aims to investigate the hypothesis (1) whether self-reported distress (as indicated by arousal, e.g., feeling tense/agitated, and/or valence, e.g., feeling discontent/unwell) and physiological reactivity increase before dissociative episodes and (2) whether self-reported distress and physiological reactivity decrease during and after dissociative episodes in a transdiagnostic sample of patients with DD, BPD, and/or PTSD.

METHODS

We will use a smartphone application to assess affect and dissociation 12 times per day over the course of one week in everyday life. During this time, heart and respiratory rates will be remotely monitored. Afterwards, participants will report affect and dissociative states eight times in the laboratory before, during, and after the Trier Social Stress Test. During the laboratory task, we will continuously record heart rate, electrodermal activity, and respiratory rate, as well as measure blood pressure and take salivary samples to determine cortisol levels. Our hypotheses will be tested using multilevel structural equation models. Power analyses determined a sample size of 85.

DISCUSSION

The project will test key predictions of a transdiagnostic model of dissociation based on the idea that dissociative reactions are affect contingent and serve affect regulation functions. This project will not include non-clinical control participants. In addition, the assessment of dissociation is limited to pathological phenomena.

Spanish validation of the Detachment and Compartmentalization Inventory (DCI) in a community and clinical sample. A new instrument for measuring dissociation

INTRODUCTION

Dissociative symptoms are a type of phenomenon which is present in a wide variety of psychopathological disorders. It is therefore necessary to develop scales that measure this type of experience for therapy and research. Starting out from the bipartite model of dissociation, this study intended to adapt and validate the Detachment and Compartmentalization Inventory (DCI) in Spanish.

MATERIAL AND METHODS

For this, 308 participants (268 from the community population and 40 with psychiatric pathology) completed the DCI, the Dissociative Experiences Scale (DES-II), the Somatoform Dissociation Questionnaire (SDQ20) and the Mindfulness Attention Awareness Scale (MAAS).

RESULTS

The results showed that the Spanish version has a two-factor structure similar to the original version and was invariant across participants. The reliability of DCI scores was adequate and acquired evidence of validity related to other instruments.

CONCLUSIONS

It is concluded that the DCI is a valid scale for detecting detachment and compartmentalization dissociative experiences, both in the clinic and research.

[Dissociation - an Interdisciplinary Challenge]

Dissociative phenomena are not only encountered in everyday life, but increasingly require neurological as well as psychiatric attention in practice and clinic in order to recognize and diagnose corresponding phenomena at an early stage and to provide patients with appropriate treatment. In this article, dissociative disorders, taking into account the new classification of the ICD-11, are presented and corresponding diagnostics and therapeutic measures are described.

A novel ego dissolution scale: A construct validation study

Ego dissolution (i.e., ego loss, ego disintegration, ego death, or self-loss) is a conscious state marked by a loss or diminution of one's sense of self and a lack of first-person experience. We developed a novel, valid, and internally consistent ego dissolution scale to both (a) assess trait-like aspects of ego dissolution, which have received scant attention to date, and (b) facilitate future research in a variety of contexts (e.g., personality, psychopathology, substance use/psychedelics, contemplative practices). We determined that the 10-item Ego Dissolution Scale (EDS; Cronbach's α = 0.80) and its identified subfactors of Ego-Loss (Cronbach's α = 0.84) and Unity (Cronbach's α = 0.75) were internally consistent, possessed strong convergent (e.g., depersonalization/derealization, mysticism, unusual experiences) and discriminant validity (e.g., neuroticism, social desirability). We found ego dissolution and dissociation to be empirically related yet discriminable on a statistical basis.

The Relationship Between Obsessive-Compulsive Symptoms and Dissociation: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate the relationship between dissociation and obsessive-compulsive symptoms (OCS) and disorder (OCD). Specifically, the study aimed to (a) estimate the pooled prevalence of dissociative disorders among individuals with OCD; (b) systematically review the prevalence of OCD among individuals with dissociative disorders; (c) compare the severity of dissociative symptoms between individuals with OCD and non-clinical controls; (d) estimate the association between OCS and dissociative symptoms in the clinical and non-clinical populations. A systematic search was carried out in biomedical databases from inception to January 2022 according to PRISMA guidelines. A total of 41 studies met inclusion criteria (n = 9,438, 34.3% males). The pooled prevalence of dissociative disorders in adult samples with OCD was 8% (95% CI [3, 15], k = 5). Studies on adolescent and adult patients with dissociative disorders found that 17-32% reported comorbid OCD, while a prospective study of patients with early-onset dissociative disorders found no evidence of association with OCD. Individuals affected by OCD reported more dissociative symptoms than non-clinical controls (g = .67, 95% CI [.18, 1.16], k = 9). A moderate correlation between dissociative symptoms and OCS was detected (r = .43, 95% CI [.36, .51], k = 18). Sensitivity analyses showed small/moderate correlations between dissociative experiences and specific types of obsessions and compulsions. Findings suggest that dissociative symptoms are moderately related to OCS in both clinical and non-clinical populations. Interventions aimed to reduce dissociation might improve treatment response of patients suffering from OCD.

Assessing responsiveness to direct verbal suggestions in depersonalization-derealization disorder

The dissociative disorders and germane conditions are reliably characterized by elevated responsiveness to direct verbal suggestions. However, it remains unclear whether atypical responsiveness to suggestion is similarly present in depersonalization-derealization disorder (DDD). 55 DDD patients and 36 healthy controls completed a standardised behavioural measure of direct verbal suggestibility that includes a correction for compliant responding (BSS-C), and psychometric measures of depersonalization-derealization (CDS), mindfulness (FFMQ), imagery vividness (VVIQ), and anxiety (GAD-7). Relative to controls, patients did not exhibit elevated suggestibility (g = 0.26, BF₁₀ = .11) but displayed significantly lower mindfulness (g = 1.38), and imagery vividness (g = 0.63), and significantly greater anxiety (g = 1.39). Although suggestibility did not correlate with severity of depersonalization-derealization symptoms in controls, r = -.03 [95% CI: -.36, .30], there was a weak tendency for a positive association in patients, r = .25, [95% CI: -.03, .48]. Exploratory analyses revealed that patients with more severe anomalous bodily experiences were also more responsive to suggestion, an effect not seen in controls. This study demonstrates that DDD is not characterized by elevated responsiveness to direct verbal suggestions. These results have implications for the aetiology and treatment of this condition, as well as its classification as a dissociative disorder in psychiatric nosology.

Hypnotic suggestibility in dissociative and related disorders: A meta-analysis

Elevated responsiveness to verbal suggestions is hypothesized to represent a predisposing factor for dissociative disorders (DDs) and related conditions. However, the magnitude of this effect has not been estimated in these populations nor has the potential moderating influence of methodological limitations on effect size variability across studies. This study assessed whether patients with DDs, trauma- and stressor-related disorders (TSDs), and functional neurological disorder (FND) display elevated hypnotic suggestibility. A systematic literature search identified 20 datasets. A random-effects meta-analysis revealed that patients displayed greater hypnotic suggestibility than controls, Hedges's g=0.92 [0.66, 1.18]. This effect was observed in all subgroups but was most pronounced in the DDs. Although there was some evidence for publication bias, a bias-corrected estimate of the group effect remained significant, g=0.57 [0.30, 0.85]. Moderation analyses did not yield evidence for a link between effect sizes and methodological limitations. These results demonstrate that DDs and related conditions are characterized by elevated hypnotic suggestibility and have implications for the mechanisms, risk factors, and treatment of dissociative psychopathology.

False Memory Researchers Misunderstand Repression, Dissociation and Freud

Various authors have argued that dissociative amnesia is a synonym for repressed memories, recovered memories are almost always false memories, and dissociative amnesia and dissociative identity disorder are not valid disorders. These authors commit numerous errors of logic and scholarship; they misunderstand Freud's thinking about childhood sexual abuse, dissociation and repression and blame both Freudian repression theory and Freudian therapists for an epidemic of false memories. In fact, however, Freudian repression theory is based on the assumption that the childhood sexual abuse never happened. Extreme skeptics about dissociative amnesia do not understand they are actually in agreement with Freudian repression theory. These errors and other failures of logic and scholarship are analyzed and critiqued in the present paper.

Dissociation, trauma, and borderline personality disorder

Dissociation is a complex phenomenon, which occurs in various clinical conditions, including dissociative disorders, (complex) post-traumatic stress disorder (CPTSD, PTSD), and borderline personality disorder (BPD). Traumatic stress is considered an important risk factor, while the etiology of dissociation is still debated. Next to traumatic experiences, temperamental and neurobiological vulnerabilities seem to contribute to the development of dissociation. Stress-related dissociation is a prevalent symptom of BPD, which may interfere with psychosocial functioning and treatment outcome. More research in the field is strongly needed to improve the understanding and management of this complex phenomenon. This article collection brings together research on dissociation and trauma, with a special focus on BPD or sub-clinical expressions of BPD. In this editorial, recent conceptualizations of dissociation and relevant previous research are introduced in order to provide a framework for this novel research.

Beyond words: Conceptual framework for the study and practice of hypnotherapeutic imagery

This paper provides a conceptual framework for the study and clinical application of hypnotherapeutic imagery (HTI). Using the grounded theory method of conceptual analysis, a unified theoretical framework is constructed from a multidisciplinary review of literature (i.e., this new theory is based on the collection and analysis of independently sourced data). The aim is to enumerate the chorographical features of HTI simulations within the mental landscape, rather than seeking to predict them. This is achieved using a combination of ontological, epistemological, and methodological inquires. Because mental simulation is both symptomatic of mental disorders and a psychotherapeutic agent, used across various treatment modalities, an attempt is made to isolate those variables that differentiate HTI from other instances of mental simulation. Lastly, applied principles from multiple disciplines are used to formulate HTI methodology designed to effectively enhance intuitive understanding and unconscious problem-solving.

Psychological mechanisms connected to dissociation: Generating hypotheses using network analyses

A large number of mechanisms, many relating to the processing of affect, have been proposed to cause dissociation. The aim of this study was to use network analyses to identify psychological processes most closely connected with 'felt sense of anomaly' dissociative experiences. Both an undirected model and a partially directed network model were estimated using data from 6161 general population respondents collected online. The networks were used to identify relationships between dissociation and ten candidate mechanisms: cognitive appraisals, behavioural responses to dissociation, affect intolerance, alexithymia, attentional control, body vigilance, anxiety sensitivity, general self-efficacy, perseverative thinking, and beliefs regarding stress. Both models indicated a highly connected network in which dissociation had direct connections with six psychological processes: cognitive appraisals, behavioural responses, perseverative thinking, alexithymia, general self-efficacy, and beliefs about being overwhelmed. The strongest connection in both networks was between dissociation and cognitive appraisals (causal effect 0.73). The causal direction of connections could not be statistically determined with confidence, apart from the strong probability that dissociation causes meta-cognitions about being overwhelmed (98.54% of 50,000 sampled directed acyclic graphs). Both networks suggest that cognitive appraisals and factors relating to heightened (negative) sensitivity to affect are closely connected to dissociation. Dissociative experiences may arise from a high sensitivity to affect leading to threat-based appraisals that are ruminated upon and maintained by unhelpful behaviours such as avoidance. Investigation of these relationships in clinical groups, and direct causal tests, are required.

The Computations of a Traumatized Mind: A Latent Cause Model of Posttraumatic Stress Disorder

In cognitive psychology, a recent perspective based on the notion of latent cause (LC) has offered new insight on how learning and memory work. Here I explore the implications of this novel perspective to understand posttraumatic stress disorder (PTSD). The proposal is that, because of a propensity to interpret events as manifestations of multiple LCs (a propensity facilitated by experiencing traumas in childhood), PTSD patients form an LC associated with the trauma and that this LC is responsible for typical symptoms of the illness (specifically, intrusive symptoms and associated fear). Later, after the trauma, some patients develop a second LC, now associated with the presence of trauma-related cues combined with absence of danger. Development of the latter LC would interfere with extinction and explain why, for some patients, exposure to trauma-related cues (even when supported by interventions such as exposure protocols) fails to provide much improvement. This proposal has potential clinical implications, raising the possibility that some patients might benefit from exposure to mildly painful aspects of the trauma in conjunction with trauma-related cues.

Dissociation and Dissociative Disorders Reconsidered: Beyond Sociocognitive and Trauma Models Toward a Transtheoretical Framework

For more than 30 years, the posttraumatic model (PTM) and the sociocognitive model (SCM) of dissociation have vied for attention and empirical support. We contend that neither perspective provides a satisfactory account and that dissociation and dissociative disorders (e.g., depersonalization/derealization disorder, dissociative identity disorder) can be understood as failures of normally adaptive systems and functions. We argue for a more encompassing transdiagnostic and transtheoretical perspective that considers potentially interactive variables including sleep disturbances; impaired self-regulation and inhibition of negative cognitions and affects; hyperassociation and set shifts; and deficits in reality testing, source attributions, and metacognition. We present an overview of the field of dissociation, delineate uncontested and converging claims across perspectives, summarize key multivariable studies in support of our framework, and identify empirical pathways for future research to advance our understanding of dissociation, including studies of highly adverse events and dissociation. Expected final online publication date for the Annual Review of Clinical Psychology, Volume 18 is May 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Dissociative Symptoms are Highly Prevalent in Adults with Narcolepsy Type 1

INTRODUCTION

The core symptoms of narcolepsy such as excessive daytime sleepiness and cataplexy are well known. However, there is mounting evidence for a much broader symptom spectrum, including psychiatric symptoms. Disordered sleep has previously been linked with dissociative symptoms, which may imply that patients with narcolepsy are more prone to develop such symptoms.

OBJECTIVES

To investigate the frequency of dissociative symptoms in adult patients with narcolepsy type 1 compared to population controls.

METHODS

In a retrospective case control study, sixty adult patients fulfilling the criteria for narcolepsy type 1 and 120 matched population control subjects received a structured interview using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) to assess dissociative symptoms and disorders.

RESULTS

A majority of narcolepsy patients reported dissociative symptoms, and even fulfilled the DSM-IV-TR criteria of a dissociative disorder (62% vs 1% in controls, p < .001). Most frequently reported symptoms were "dissociative amnesia" (37% vs 1%, p < .001) and "dissociative disorder of voluntary movement" (32% vs 1%, p < .001).

CONCLUSION

Dissociative symptoms are strikingly prevalent in adult patients with narcolepsy type 1. Although a formal diagnosis of dissociation disorder should not be made as the symptoms can be explained by narcolepsy as an underlying condition, the findings do illustrate the extent and severity of the dissociative symptoms. As for the pathophysiological mechanism, there may be symptom overlap between narcolepsy and dissociation disorder. However, there may also be a more direct link between disrupted sleep and dissociative symptoms. In either case, the high frequency of occurrence of dissociative symptoms should result in an active inquiry by doctors, to improve therapeutic management and guidance.

Pharmacological modelling of dissociation and psychosis: an evaluation of the Clinician Administered Dissociative States Scale and Psychotomimetic States Inventory during nitrous oxide ('laughing gas')-induced anomalous states

RATIONALE

A significant obstacle to an improved understanding of pathological dissociative and psychosis-like states is the lack of readily implemented pharmacological models of these experiences. Ketamine has dissociative and psychotomimetic effects but can be difficult to use outside of medical and clinical-research facilities. Alternatively, nitrous oxide (N₂O) - like ketamine, a dissociative anaesthetic and NMDAR antagonist - has numerous properties that make it an attractive alternative for modelling dissociation and psychosis. However, development and testing of such pharmacological models relies on well-characterized measurement instruments.

OBJECTIVES

To examine the factor structures of the Clinician Administered Dissociative States Scale (CADSS) and Psychotomimetic States Inventory (PSI) administered during N₂O inhalation in healthy volunteers.

METHODS

Secondary analyses of data pooled from three previous N₂O studies with healthy volunteers.

RESULTS

Effect sizes for N₂O-induced dissociation and psychotomimesis were comparable to effects reported in experimental studies with sub-anaesthetic ketamine in healthy volunteers. Although, like ketamine, a three-factor representation of N₂O-induced dissociation was confirmed, and a more parsimonious two-factor model might be more appropriate. Bayesian exploratory factor analysis suggested that N₂O-induced psychosis-like symptoms were adequately represented by two negative and two positive symptom factors. Hierarchical cluster analysis indicated minimal item overlap between the CADSS and PSI.

CONCLUSION

N₂O and ketamine produce psychometrically similar dissociative states, although parallels in their psychosis-like effects remain to be determined. The CADSS and PSI tap largely non-overlapping experiences under N₂O and we propose the use of both measures (or similar instruments) to comprehensively assess anomalous subjective states produced by dissociative NMDAR antagonists.

Prevalence and risk factors for acute stress disorder in female victims of sexual assault

Sexual assault is one of the most traumatic events a person can experience. Despite this, information regarding the risk factors associated with the development of Acute Stress Disorder (ASD) in sexual assault victims is scarce. A follow-up prospective cohort study was designed to examine the prevalence and risk factors of ASD in women exposed to a recent sexual assault. A total of 156 women were treated at the Emergency Department of a university general hospital shortly after sexual assault. Sociodemographic, clinical and sexual assault-related variables were collected. The Acute Stress Disorder Interview was used to estimate the prevalence of ASD at three weeks post-SA. From the 156 victims, 66.6% (N = 104) met ASD diagnosis using DSM-5 criteria, whereas 59.6% (N = 93) met ASD diagnosis using DSM-IV criteria. The risk factors associated with the development of ASD were nationality, psychiatric history, peritraumatic dissociation and type of assault. In conclusion, the prevalence of ASD in female victims of recent sexual assault was high, affecting approximately two thirds of them. The recognition of the risk factors associated with ASD development, like peritraumatic dissociation or type of assault, may aid in the prompt detection of vulnerable women that require early and specific interventions shortly after trauma.

The link between dissociative tendencies and hyperassociativity

BACKGROUND AND OBJECTIVES

Anecdotal and research evidence suggests that individuals with dissociative symptoms exhibit hyperassociativity, which might explain several key features of their condition. The aim of our study was to investigate the link between dissociative tendencies and hyperassociativity among college students.

METHODS

The study (n = 118) entailed various measures of hyperassociativity, measures of dissociative tendencies, depressive experiences, unusual sleep experiences, cognitive failures, and alexithymia.

RESULTS

We found a positive association between dissociative experiences (i.e., depersonalization) and hyperassociativity specific for associative fluency and associative flexibility tasks (including neutral and valenced material), but not for a remote association task. We also found tentative evidence for cognitive failures and alexithymia explaining the link between hyperassociativity and daytime dissociation and nighttime unusual sleep experiences.

LIMITATIONS

Limitations include the use of hyperassociation tasks limited to verbal associations vs. imagistic associations, the lack of a measure of trauma history, and a sample limited to college students.

CONCLUSION

Our study reports a link between depersonalization and hyperassociativity on tasks that allow for free associations across different semantic domains, potentially explained by alexithymia and cognitive failures. This finding may, with replication, open the pathway to applied intervention studies.

Lived Experiences of Women with Dissociative Disorder: An Interpretative Phenomenological Analysis

BACKGROUND

In the Indian setting, several studies have documented that dissociative disorders (DDs) are more common in females, and the most commonly elicited stressors are interpersonal. However, much of the research up to now has been quantitative. There is a notable paucity of qualitative studies exploring the subjective experiences of women with DD. Therefore, the present study sought to explore and gain an in-depth understanding of the lived experiences of women diagnosed with DD.

METHODS

Five women were recruited who were seeking psychological treatment for dissociative symptoms at a tertiary care neuropsychiatric institute in North India. In-depth interviews were conducted with each, and the transcripts were analyzed using the analytic method of interpretative phenomenological analysis.

RESULTS

Three superordinate themes that emerged were: patients' illness perspectives, the salience of relationships, and dealing with relationship conflicts.

CONCLUSIONS

Our findings highlight the role of culture in influencing the participants' illness perspectives. Women with DD tend to define their self in relational terms and, thus, inhibit the expression of one's needs and opinions, to avoid conflict and to maintain harmony in relationships.

A Network Analysis to Identify Associations between PTSD and Dissociation among Teenagers

We conducted a network analysis of measures of dissociation and posttraumatic symptoms (PTS) with a varied sample of adolescents (N = 312), some of them previously exposed to war scenarios. The global measure of dissociation (A-DES) was uniquely linked to the arousal PTS symptom cluster (CRIES-13), in particular sleep problems, but not to the reexperiencing and avoidance clusters. Three of four (i.e., depersonalization/derealization, amnesia, mental partition/compartmentalization) dissociation clusters were uniquely linked to PTS severity, but not absorption. The results with the pooled groups were generally representative of both groups. The DP/DR relation to PTS was based on data from both samples, whereas the link between amnesia and partition/parts might have been driven by the normative group, although the refugee sample had significantly higher scores in those variables. The results replicate some previous findings with adult samples and suggest new paths for research and theory.

Believing in dissociative amnesia relates to claiming it: a survey of people's experiences and beliefs about dissociative amnesia

Dissociative amnesia is one of the most controversial categories in the field of psychiatry and clinical psychology. Self-reports of dissociative amnesia in the general population, and beliefs about this topic, have so far not been subjected to empirical scrutiny. Here, we surveyed a sample from the general population (N = 1017), revealing that about a tenth (n = 102) claimed to have experienced dissociative amnesia. Some claims pertained to amnesia for traumatic autobiographical experiences (e.g., sexual assault), while other claims reflected memory loss for experiences that can be regarded as non-traumatic or non-stressful (e.g., dissociative amnesia for an anniversary). Importantly, many participants believed in the existence of dissociative amnesia, and those who claimed dissociative amnesia indicated even more belief in this phenomenon than the rest of the sample. Finally, many participants indicated to have at least once claimed to have feigned memory loss in their life, and that they experienced some form of forgetting when trying to retrieve events for which they lied upon. Overall, our findings suggest that claiming dissociative amnesia goes hand in hand with believing in dissociative amnesia.

Dissociation in relation to other mental health conditions: An exploration using network analysis

Dissociative experiences, traditionally studied in relation to trauma and PTSD, may be important phenomena across many different psychological conditions, including as a contributory causal factor for psychotic experiences. In this study, the aim was to explore, using network approaches, how dissociative experiences taking the form of a Felt Sense of Anomaly (FSA) relate to both common mental health conditions and psychotic experiences. 6941 individuals from the general population completed online assessments of FSA-dissociation, post-traumatic stress symptoms (PTSS), anxiety, depression, insomnia, worry, distress tolerance, hallucinations, grandiosity, paranoia, and cognitive disorganization. An undirected partial correlation network analysis was used to explore the network structure, then Bayesian inference with Directed Acyclic Graphs (DAGs) was used to identify potential directions of relationships between dissociation and mental health symptoms. Dissociation was found to be highly connected in both network models. Both networks found direct relationships between dissociation and hallucinations, grandiosity, paranoia, cognitive disorganization, anxiety, depression, and PTSS. In the DAGs analysis, the direction of influence between dissociation and hallucinations, PTSS, anxiety and depression was unclear, however it was found to be probable that dissociation influences paranoia (97.66% of sampled DAGs found the direction dissociation to paranoia, versus 2.34% finding the reverse direction), cognitive disorganization (99.74% vs. 0.26%), and grandiosity (93.49% vs. 6.51%). Further, dissociation was found to be a probable influence of insomnia and distress tolerance via indirect pathways. In summary, dissociation is connected to many mental health disorders, and may influence a number of presentations, particularly psychotic experiences. The importance of dissociation in mental health may therefore currently be under-recognised.

The path to dissociative experiences: A direct comparison of different etiological models

Severe dissociation is trauma-related, but a range of dissociative experiences are also prevalent in clinical populations that are not necessarily trauma-based (e.g., depression, anxiety disorders, and obsessive-compulsive disorders). These remain poorly understood as the dominant etiological model for dissociation relies on trauma. Importantly, dissociation in such samples predicts poor prognosis and high drop-out rates. We set out to better understand the aetiology of dissociative experiences in a mixed clinical (anxiety and depression) and community sample by exploring between- and within-subjects effects of two domains: psychological distress or negative affectivity (operationalized as anxiety and depression symptoms), and poor sleep quality, including disturbed dreaming. The idea that negative affectivity triggers dissociation (Distress Model) is inspired by the trauma model. The idea that poor sleep and unusual dreaming underlie dissociation (Sleep Model) has been suggested as a competing theory. We examined both models by exploring which domains oscillate alongside dissociative experiences. N = 98 adults, half of them diagnosed with depression and anxiety and half community controls, underwent a structured clinical interview and completed questionnaires monthly for 6 months. Support was found for both models in that each domain had a unique explanatory contribution. Distress evinced consistent effects that could not be explained by sleep or dreaming, both between individuals and across time. Oscillations in dissociation across months, when taking psychological distress into account, were better explained by unusual dreaming than traditional sleep quality measures. These findings cannot be generalized to highly-traumatized samples. A complex, integrated etiological model for dissociative experiences is warranted.

A new perspective and assessment measure for common dissociative experiences: 'Felt Sense of Anomaly'

BACKGROUND

Dissociative experiences occur across a range of mental health disorders. However, the term 'dissociation' has long been argued to lack conceptual clarity and may describe several distinct phenomena. We therefore aimed to conceptualise and empirically establish a discrete subset of dissociative experiences and develop a corresponding assessment measure.

METHODS

First, a systematic review of existing measures was carried out to identify themes across dissociative experiences. A theme of 'Felt Sense of Anomaly' (FSA) emerged. Second, assessment items were generated based on this construct and a measure developed using exploratory (EFA) and confirmatory (CFA) factor analyses of 8861 responses to an online self-report survey. Finally, the resulting measure was validated via CFA with data from 1031 patients with psychosis.

RESULTS

'Felt sense of anomaly' (FSA) was identified as common to many dissociative experiences, affecting several domains (e.g. body) and taking different forms ('types'; e.g. unfamiliarity). Items for a novel measure were therefore systematically generated using a conceptual framework whereby each item represented a type-by-domain interaction (e.g. 'my body feels unfamiliar'). Factor analysis of online responses found that FSA-dissociation manifested in seven ways: anomalous experiences of the self, body, and emotion, and altered senses of familiarity, connection, agency, and reality (Χ2 (553) = 4989.435, p<0.001, CFI = 0.929, TLI = 0.924, RMSEA = 0.052, SRMR = 0.047). Additionally, a single-factor 'global FSA' scale was produced (Χ2 (9) = 312.350, p<0.001, CFI = 0.970, TLI = 0.950, RMSEA = 0.107, SRMR = 0.021). Model fit was adequate in the clinical (psychosis) group (Χ2 (553) = 1623.641, p<0.001, CFI = 0.927, TLI = 0.921, RMSEA = 0.043, SRMR = 0.043). The scale had good convergent validity with a widely used dissociation scale (DES-II) (non-clinical: r = 0.802), excellent internal reliability (non-clinical: Cronbach's alpha = 0.98; clinical: Cronbach's alpha = 0.97), and excellent test-retest reliability (non-clinical: ICC = 0.92). Further, in non-clinical respondents scoring highly on a PTSD measure, CFA confirmed adequate model fit (Χ2 (553) = 4758.673, CFI = 0.913, TLI = 0.906, RMSEA = 0.052, SRMR = 0.054).

CONCLUSIONS

The Černis Felt Sense of Anomaly (ČEFSA) scale is a novel measure of a subset of dissociative experiences that share a core feature of FSA. It is psychometrically robust in both non-clinical and psychosis groups.

Poor sleep efficiency and daytime napping are risk factors of depersonalization disorder in female university students

Objectives

Depersonalization is characterized by feelings of detachment from reality and has been associated with anxiety and depression, both of which have a bi-directional relationship with sleep. To date, few studies have directly examined the potential relationship between sleep and depersonalization, which was the primary objective of our study.

Design/methods

A cross-sectional study of female, Emirati, university students (n = 100) was conducted. Participants completed the Pittsburgh Sleep Quality Index (PSQI), the Cambridge Depersonalization Scale (CDS) and the Hospital Anxiety and Depression Scale (HADS). Additionally, 36 of the 100 participants wore wrist actigraphy for two consecutive weekdays. Average sleep duration, and average sleep efficiency (SE; %) across the two nocturnal sleep episodes were calculated. Total number of sleep episodes were obtained from wrist actigraphy and sleep logs.

Results

A significant, positive relationship was observed between PSQI global score and CDS total score (r = 0.21, p = 0.04). Actigraphy-estimated average nocturnal sleep duration was not significantly associated with the CDS. Compared to nocturnal sleepers only, those who undertook daytime naps had almost three times the risk of meeting the criteria for depersonalization disorder (OR = 2.95, 95% CI: 1.04–8.41), after adjustment. For each 1% increase in SE a 23% decreased risk of depersonalization was observed (OR = 0.77, 95% CI: 0.61–0.96), after adjustment.

Conclusions

Sleep screening in young adults may help to ensure better detection and management of psychological health outcomes. Our findings need to be confirmed prospectively in larger samples and amongst different populations but reiterate the importance of sleep habits pertaining to mental health.

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We show a novel relationship between depersonalization and sleep in a non-clinical sample.

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Actigraphy determined poor sleep efficiency was significantly associated with subjective reports of depersonalization.

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Daytime nappers were ~3 times more likely to report depersonalization symptoms and meet the diagnositic criteria.

Biomarkers of Pathological Dissociation: A Systematic Review

Pathological dissociation is a severe, debilitating and transdiagnostic psychiatric symptom. This review identifies biomarkers of pathological dissociation in a transdiagnostic manner to recommend the most promising research and treatment pathways in support of the precision medicine framework. A total of 205 unique studies that met inclusion criteria were included. Studies were divided into four biomarker categories, namely neuroimaging, psychobiological, psychophysiological and genetic biomarkers. The dorsomedial and dorsolateral prefrontal cortex, bilateral superior frontal regions, (anterior) cingulate, posterior association areas and basal ganglia are identified as neurofunctional biomarkers of pathological dissociation and decreased hippocampal, basal ganglia and thalamic volumes as neurostructural biomarkers. Increased oxytocin and prolactin and decreased tumor necrosis factor alpha (TNF-α) are identified as psychobiological markers. Psychophysiological biomarkers, including blood pressure, heart rate and skin conductance, were inconclusive. For the genetic biomarker category studies related to dissociation were limited and no clear directionality of effect was found to warrant identification of a genetic biomarker. Recommendations for future research pathways and possible clinical applicability are provided.

Losing Control: Sleep Deprivation Impairs the Suppression of Unwanted Thoughts

Unwanted memories often enter conscious awareness when individuals confront reminders. People vary widely in their talents at suppressing such memory intrusions; however, the factors that govern suppression ability are poorly understood. We tested the hypothesis that successful memory control requires sleep. Following overnight sleep or total sleep deprivation, participants attempted to suppress intrusions of emotionally negative and neutral scenes when confronted with reminders. The sleep-deprived group experienced significantly more intrusions (unsuccessful suppressions) than the sleep group. Deficient control over intrusive thoughts had consequences: Whereas in rested participants suppression reduced behavioral and psychophysiological indices of negative affect for aversive memories, it had no such salutary effect for sleep-deprived participants. Our findings raise the possibility that sleep deprivation disrupts prefrontal control over medial temporal lobe structures that support memory and emotion. These data point to an important role of sleep disturbance in maintaining and exacerbating psychiatric conditions characterized by persistent, unwanted thoughts.

Describing the indescribable: A qualitative study of dissociative experiences in psychosis

Background

Despite its long history, dissociation remains under-recognised clinically, partly due to difficulties identifying dissociative symptoms. Qualitative research may support its recognition by providing a lived experience perspective. In non-affective psychosis, identification of dissociation may be particularly important given that such experiences have been implicated its development and maintenance. Therefore, this study aimed to understand in the context of psychosis: what it is like to experience dissociation; the impact dissociation might have; what factors begin, maintain or end dissociative experiences; and what beliefs people hold about dissociation.

Methods

Qualitative interviews were carried out with twelve NHS patients with non-affective psychosis diagnoses and experience of dissociation. Data were analysed using Thematic Analysis.

Results

Dissociation involves subjective strangeness, unreality, disconnection, and shifts in perception. It impacts on mental health (including psychotic experiences), daily functioning, emotional connection, and can lead to social withdrawal. Stress, fatigue, and excessive internal focus may be involved in development and maintenance. Participants found it very difficult to describe the experience of dissociation, and, as a result, often did not mention it to others. Even when shared, interviewees reported that their descriptions were misunderstood and therefore they did not receive information or support specific to dissociation. The consensus was that experiences of dissociation are negative, but that understanding them better helped to enable coping.

Conclusions

The core subjective experience of dissociation appears to be a felt sense of anomaly (FSA), and we therefore suggest clinicians proactively enquire about such experiences. Dissociation is distressing, and has multiple impacts, but can easily be overlooked due to difficulties describing it and behavioural similarities to negative psychotic symptoms such as withdrawal.

Reports of recovered memories of childhood abuse in therapy in France

Recovered memories of abuse in therapy are especially controversial if the clients were not aware they were abused before therapy. In the past, such memory recovery has led to legal action, as well as a debate about whether such memories might be repressed, forgotten, or false memories. More than two decades after the height of the controversy, it is unclear to what degree such memories are still recovered today, and to what extent it occurs in France. In our French survey of 1312 participants (M_age = 33; 53% female), 551 reported having done therapy at some point. Of that 551, 33 (6%) indicated they had recovered memories of abuse in therapy that they did not know about before therapy. Sexual abuse was the most commonly reported type that was recovered in therapy (79%). As in past research, discussing the possibility of repressed memories with therapists was associated with reports of recovered memories of abuse. Surprisingly, memory recovery occurred just as much in behavioural and cognitive therapies as it did in therapies focused on trauma. We found recovered memories in a proportion of clients who began therapy recently. Recovered memories in therapy appears to be an ongoing concern in France.