Prevalence and childhood antecedents of depersonalization syndrome in a UK birth cohort

Lost in time and space? Multisensory processing of peripersonal space and time perception in people with frequent experiences of depersonalisation

Perception of one's own body in time and space is a fundamental aspect of self-consciousness. It scaffolds our subjective experience of being present, in the here and now, a vital condition for our survival and well-being. Depersonalisation (DP) is characterised by a distressing feeling of being "spaced out," detached from one's self, as well as atypical "flat" time perception. Using an audio-tactile paradigm, we conducted a study looking at the effect of DP experiences on peripersonal space (PPS)-the space close to the body-and time perception. Strikingly, we found no difference in PPS perception in people with higher DP experiences (High DPe) versus low occurrences of DP experiences (Low DPe). To assess time perception, we used the mental time travel (MTT) task measuring the individuals' capacity to take one's present as a reference point for situating personal versus general events in the past and the future. We found an overall poorer performance in locating events in time relative to their present reference point in High DPe. By contrast, Low DPe showed significant variation in performance when answering to relative past events, while High DPe did not. Our study sheds light on the close link between altered sense of self and egocentric spatiotemporal perception in individuals with DP experiences, the third most common psychological symptom in the general population.

Clinical characteristics of 217 Chinese cases with depersonalization/derealization disorder

Depersonalization/derealization disorder (DPD) is a prevalent yet inadequately understood clinical condition characterized by a recurrent or persistent sense of unreality. This study aims to provide insight into DPD through descriptive and comparative analyses involving a large group of Chinese participants. The socio-demographic details (age, gender proportion, education, occupational status, marital status), depersonalized and dissociative symptom characteristics (symptomatic factors or subscales of the Cambridge Depersonalization Scale and the Dissociative Experiences Scale), development trajectory (age of onset, potential precipitating factors, course characteristics), treatment history (duration of delayed healthcare attendance, duration of delayed diagnosis, previous diagnoses), and adverse childhood experiences of the DPD patients are presented. Comparisons of anxiety and depressive symptoms, alongside psychosocial functioning, between DPD participants and those diagnosed with generalized anxiety disorder, bipolar disorders, and major depressive disorder were conducted. The analysis highlights a higher male preponderance and early onset of DPD, symptomatology marked by derealization, notable impairment in psychosocial functioning, and prolonged periods of delayed healthcare attendance and diagnosis associated with symptom severity. Furthermore, noteworthy relationships between adverse childhood experiences and symptom levels were identified. The findings substantiate the view that DPD is a serious but neglected mental disorder, urging initiatives to improve the current condition of DPD patients.

Confrontation with others' emotions changes bodily resonance differently in those with low and high levels of depersonalization

We present novel research on the cortical dynamics of atypical perceptual and emotional processing in people with symptoms of depersonalization-derealization disorder (DP-DR). We used electroencephalography (EEG)/event-related potentials (ERPs) to delineate the early perceptual mechanisms underlying emotional face recognition and mirror touch in adults with low and high levels of DP-DR symptoms (low-DP and high-DP groups). Face-sensitive visual N170 showed markedly less differentiation for emotional versus neutral face-voice stimuli in the high- than in the low-DP group. This effect was related to self-reported bodily symptoms like disembodiment. Emotional face-voice primes altered mirror touch at somatosensory cortical components P45 and P100 differently in the two groups. In the high-DP group, mirror touch occurred only when seeing touch after being confronted with angry face-voice primes. Mirror touch in the low-DP group, however, was unaffected by preceding emotions. Modulation of mirror touch following angry others was related to symptoms of self-other confusion. Results suggest that others' negative emotions affect somatosensory processes in those with an altered sense of bodily self. Our findings are in line with the idea that disconnecting from one's body and self (core symptom of DP-DR) may be a defence mechanism to protect from the threat of negative feelings, which may be exacerbated through self-other confusion. This article is part of the theme issue 'Sensing and feeling: an integrative approach to sensory processing and emotional experience'.

Explicit and implicit sense of agency in depersonalisation experiences

The sense of agency, the feeling of controlling one's bodily actions and the world is altered in Depersonalisation (DP), a condition that makes people feel detached from one's self and body. To investigate the link between depersonalisation and both implicit and explicit sense of agency, an online study was conducted using the influential Intentional Binding paradigm in a sample of non-clinical DP participants. The results did not reveal significant differences between individuals with low and high occurrences of DP experiences on the implicit and explicit sense of agency. However, participants with high occurrences of DP experiences showed a more time-sensitive explicit sense of agency and greater temporal distortions for short intervals in the absence of self-initiated motion. These results suggest that there is a discrepancy between implicit and explicit sense of agency in people with high levels of depersonalisation. Altogether, these findings call for further investigations of the key role of time perception on altered sense of self and agency in both non-clinical and clinical populations, to disentangle the mechanisms associated with the explicit and implicit sense of agency.

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.

The Treatment of Depersonalization-Derealization Disorder: A Systematic Review

Depersonalization-derealization disorder (DPD) is characterized by persistent or recurrent experiences of detachment from oneself and surroundings, as well as a sense of unreality. Considering the inadequacy of current research on treatment, we performed a systematic review of the available pharmacotherapies, neuromodulations, and psychotherapies for DPD. The systematic review protocol was based on PRISMA 2020 guidelines and pre-registered. The PubMed, Web of Science, PsycINFO, Embase, the Cochrane Library, Scopus, and ScienceDirect databases were searched from inception to June 2021. All treatments for DPD and all study types, including controlled and observational studies as well as case reports, were assessed. Of the identified 17,540 studies, 41 studies (four randomized controlled trials, one non-randomized controlled trial, 10 case series, and 26 case reports) involving 300 participants met the eligibility criteria. We identified 30 methods that have been applied independently or in combination to treat DPD since 1955. The quality of these studies was considered. The relationship between individual differences, such as symptoms, comorbidities, history, and duration since onset, and treatment effects was explored. The results suggest that a series of treatments, such as pharmacotherapies, neuromodulation, and psychotherapies, could be considered in combination. However, the quality and quantity of studies were generally low considering the high prevalence of DPD. The review concludes with suggestions for future research and an urgent call for more high-quality research.

Review of Major Social Determinants of Health in Schizophrenia-Spectrum Disorders: II. Assessments

BACKGROUND AND AIMS

Social determinants of health (SDoHs) impact the development and course of schizophrenia-spectrum psychotic disorders (SSPDs). Yet, we found no published scholarly reviews of psychometric properties and pragmatic utility of SDoH assessments among people with SSPDs. We aim to review those aspects of SDoH assessments.

STUDY DESIGN

PsychInfo, PubMed, and Google Scholar databases were examined to obtain data on reliability, validity, administration process, strengths, and limitations of the measures for SDoHs identified in a paired scoping review.

STUDY RESULTS

SDoHs were assessed using different approaches including self-reports, interviews, rating scales, and review of public databases. Of the major SDoHs, early-life adversities, social disconnection, racism, social fragmentation, and food insecurity had measures with satisfactory psychometric properties. Internal consistency reliabilities-evaluated in the general population for 13 measures of early-life adversities, social disconnection, racism, social fragmentation, and food insecurity-ranged from poor to excellent (0.68-0.96). The number of items varied from 1 to more than 100 and administration time ranged from less than 5 minutes to over an hour. Measures of urbanicity, low socioeconomic status, immigration status, homelessness/housing instability, and incarceration were based on public records or targeted sampling.

CONCLUSIONS

Although the reported assessments of SDoHs show promise, there is a need to develop and test brief but validated screening measures suitable for clinical application. Novel assessment tools, including objective assessments at individual and community levels utilizing new technology, and sophisticated psychometric evaluations for reliability, validity, and sensitivity to change with effective interventions are recommended, and suggestions for training curricula are offered.

Developing an understanding of the relationship between anxiety and dissociation in adolescence

Anxiety is a common problem in adolescence which is hypothesised to be associated with dissociation, a range of distressing symptoms linked to reduced psychosocial functioning. Yet, to date, research into the mechanisms of dissociation in adolescents has been limited. The present study investigated the link between trait anxiety and dissociative experiences (depersonalisation and 'felt sense of anomaly') using an online survey. Cognitive appraisals of dissociation, perseverative thinking, and body vigilance were assessed as potential mediating factors of this relationship. 1211 adolescents aged 13-18 years were recruited via social media advertisements and local schools. Linear regression showed a moderate positive relationship between trait anxiety and both dissociation constructs. Hierarchical regression indicated that cognitive appraisals of dissociation and perseverative thinking mediated the relationship between trait anxiety and both dissociation constructs, but trait anxiety was a significant predictor for felt sense of anomaly but not depersonalisation after including the mediators. The final models accounted for 58.7% of variance in depersonalisation and 68.4% of variance in felt sense of anomaly. These results support the hypothesis that dissociation is associated with anxiety in adolescence. They also demonstrate that cognitive-behavioural conceptualisations may be valid for understanding dissociation in adolescence.

Depersonalization disorder as a systematic downregulation of interoceptive signals

Depersonalisation disorder (DPD) is a psychopathological condition characterised by a feeling of detachment from one's own body and surrounding, and it is understood as emerging from the downregulation of interoceptive afferents. However, the precise mechanisms that drive this 'interoceptive silencing' are yet to be clarified. Here we present a computational and neurobiologically plausible model of DPD within the active inference framework. Specifically, we describe DPD as arising from disrupted interoceptive processing at higher levels of the cortical hierarchy where the interoceptive and exteroceptive streams are integrated. We simulated the behaviour of an agent subjected to a situation of high interoceptive activation despite the absence of a perceivable threat in the external environment. The simulation showed how a similar condition, if perceived as inescapable, would result in a downregulation of interoceptive signals, whilst leaving the exteroceptive ones unaffected. Such interoceptive silencing would force the agent to over-rely on exteroceptive information and would ultimately lead to the DPD phenomenology. Finally, our simulation shows that repeated exposure to similar situations over time will lead the agent to increasingly disengage from bodily responses even in the face of a less triggering situation, explaining how a single episode of depersonalization can lead to chronic DPD.

Potential Targets for Noninvasive Brain Stimulation on Depersonalization-Derealization Disorder

INTRODUCTION

Non-invasive brain stimulation seems to be beneficial for DPD patients. However, the sites used in previous studies were empirical. Exploring new stimulation locations via functional magnetic resonance imaging may improve the efficacy.

OBJECTIVES

The objective was to find potential locations for non-invasive brain stimulation on the depersonalization-derealization disorder.

METHODS

We explored the potential brain surface regions from three pipelines: pipeline 1: activation likelihood estimation meta-analysis (five studies with 36 foci included); pipeline 2: functional connectivity analysis based on DPD-network (76 subjects included); and pipeline 3: functional connectivity analysis based on DPD regions of interest from the meta-analysis. Potential targets were the 10-20 system coordinates for brain surface regions.

RESULTS

We identified several potential brain surface regions, including the bilateral medial prefrontal cortex, dorsal lateral prefrontal cortex, superior parietal gyrus, superior temporal gyrus, and right ventrolateral prefrontal cortex as potential sites.

CONCLUSION

Our findings of the potential stimulation targets might help clinicians optimize the application of non-invasive brain stimulation therapy in individuals with DPD.

White matter abnormalities in first-episode patients with depersonalization/derealization disorder: A tract-based spatial statistics study

BACKGROUND

Neuroimaging studies on depersonalization / derealization disorder (DPD) have revealed that there are structural and functional alterations across numerous brain regions. However, to date, the exact white matter abnormalities that are associated with different clinical symptoms and cognitive impairments in first-episode, drug-naïve patients with DPD remain unclear.

METHODS

Overall, 25 first-episode, drug-naïve patients with DPD and 23 healthy controls were recruited and underwent DTI scans. The tract-based spatial statistics analysis was conducted in order to determine white matter microstructural changes between the two groups. Correlation analysis was conducted between the fractional anisotropy (FA) of abnormal WM fibers and the total score of the 30-item Cambridge Depersonalization Scale (CDS-30), cognitive assessments.

RESULTS

Patients with DPD demonstrated higher FA in the right corpus callosum (CC), and posterior corona radiate (CR), compared to healthy controls. The FA in the right CC demonstrated a positive correlation with total score of CDS-30, numbing, unreality of self, perceptual alterations, and temporal disintegration, respectively. FA in the right CR region indicated a positive correlation with the total score of CDS-30, unreality of self, perceptual alterations, and temporal disintegration, respectively. Furthermore, FA in the right CR region was found to be negatively correlated with the Continuous Performance Test and the Stroop color-word test.

CONCLUSION

The altered white matter microstructure and cognitive impairments of medication naïve DPD patients were observed. Abnormalities in the integrity of CC and CR were associated with severity of symptoms and cognitive impairments, which may provide a potential biomarker for clinical studies on DPD.

Zoomed out: digital media use and depersonalization experiences during the COVID-19 lockdown

Depersonalisation is a common dissociative experience characterised by distressing feelings of being detached or 'estranged' from one's self and body and/or the world. The COVID-19 pandemic forcing millions of people to socially distance themselves from others and to change their lifestyle habits. We have conducted an online study of 622 participants worldwide to investigate the relationship between digital media-based activities, distal social interactions and peoples' sense of self during the lockdown as contrasted with before the pandemic. We found that increased use of digital media-based activities and online social e-meetings correlated with higher feelings of depersonalisation. We also found that the participants reporting higher experiences of depersonalisation, also reported enhanced vividness of negative emotions (as opposed to positive emotions). Finally, participants who reported that lockdown influenced their life to a greater extent had higher occurrences of depersonalisation experiences. Our findings may help to address key questions regarding well-being during a lockdown, in the general population. Our study points to potential risks related to overly sedentary, and hyper-digitalised lifestyle habits that may induce feelings of living in one's 'head' (mind), disconnected from one's body, self and the world.

Traumatic experiences in childhood and adolescence: a meta-analysis of prospective studies assessing risk for psychosis

Evidence of the association between traumatic experiences and psychosis are uncertain with respect to temporal order, clinical outcomes and the role of the age and genetic liability. The aim of the present meta-analysis was to explore the temporal relationship between the development of psychosis and traumatic exposure using prospective studies and to examine the role of moderation factors on overall effect sizes. Studies were identified by searching Embase-Ovid, PsycINFO (EBSCO), Pubmed, Scopus, Web of Science databases, and yielded an initial total of 9016 papers, leaving finally 23 after the screening process. Three sets of meta-analyses estimated the risk of developing psychotic experiences or full clinical psychosis by having experienced maltreatment by an adult or bullying by peers or parental death, using the random-effects model. Bullying by peers (OR = 2.28 [1.64, 4.34]), maltreatment by an adult (OR = 2.20 [1.72, 2.81]) and parental death (OR = 1.24 [1.06, 1.44]) all increased the risk of psychosis. Moderator analysis showed that negative effects of bullying were detected especially in those with genetic liability for psychosis and exposure to multiple trauma types; studies with higher prevalence of males showed a stronger risk for those exposed to parental death. No significant meta-regression was found between the risk of developing a full clinical psychosis or a psychotic experience. Lack of studies hampered the results about the age of trauma occurrence. The cumulative effect of being bullied from peers and experiencing other adversities during childhood and/or adolescence, together with genetic liability for psychosis, appears to confer the highest risk for developing psychotic symptoms later in life.

Anxiety-related Symptoms following the Sporadic Use of Ecstasy - A Case Study

3,4-methylenedioxymethamphetamine (MDMA/"ecstasy") is widespread in the electronic club scene, but MDMA has also been suggested for the treatment of anxiety spectrum disorders like posttraumatic stress disorder (PTSD) and social anxiety in autistic adults. Here, we report a case of a high functioning 24-old student with a sporadic recreational use of ecstasy, and a history of a single episode of obsessive-compulsive disorder (OCD). A few days after using ecstasy during a period of stressful life events, he developed a complex depersonalization/derealization syndrome (DDS) including intermittent distortions of time and very short intermittent episodes of misidentification of persons. Furthermore, obsessive thoughts reappeared and he suffered a panic attack for the first time in his life. Under combined pharmacological treatment and psychotherapy, symptoms gradually subsided until full remission after 14 months. Some months after discontinuation of escitalopram, however, panic attacks recurred, evolving into a regular pattern. Even if MDMA is a promising tool for the treatment of some anxiety spectrum disorders in the framework of substance-assisted psychotherapy, the use of ecstasy might be also harmful for some patients with a history of anxiety or dissociative symptoms, when used recreationally or as a self-medication outside of a controlled clinical setting.

Traumatic Events, Social Adversity and Discrimination as Risk Factors for Psychosis - An Umbrella Review

Exposure to childhood trauma is a well-known risk factor for severe mental disorders including schizophrenia and other non-affective psychoses. Beyond childhood trauma, there is increasing evidence that bullying, social exclusion, and discrimination during adolescence and adulthood may increase the risk of developing a psychotic disorder, and that such forms of traumatization may also underlie the elevated psychosis risk among migrants or persons with a visible minority status. In this umbrella review, we systematically assess meta-analyses regarding trauma and social adversity. A systematic literature review yielded 11 meta-analyses that met inclusion criteria and could be summarized quantitatively with a random effect model. Furthermore, six meta-analyses were evaluated qualitatively. Heterogeneity and publication bias were apparent in several meta-analyses. We observed that most significant social risk factors for psychosis were vulnerability for racist discrimination [OR = 3.90 (3.25-4.70)], migration [OR = 2.22 (1.75-2.80)], and childhood adversities [OR = 2.81 (2.03-3.83)]. Furthermore, social factors increasing the risk for psychosis were variation/impairment of parental communication, aversive adult life events, bullying, and factors associated with social isolation and discrimination. In spite of these environmental risk factors, there is a lack of evidence regarding treatment of trauma and psychosis, although some psychotherapeutic and art therapy approaches appear to be promising. Beyond individual interventions, stigmatization, racism, and other forms of discrimination need to be targeted to increase solidarity and communal support.

Electrodermal Activity and Stress Assessment

Stress, as a kind of emotion, is inevitable in everyday life. In psychosomatic medicine stress represents a powerful link in the pathophysiological chain of disorder. Having evidence about the power of stress on the body, the interest in medicine was how to measure it in appropriate, fast way and with minimal cost. Electrodermal activity seems to be available for this purpose. The galvanic skin response (GSR) is an objective, transient indication of autonomic nervous system arousal in response to a stimulus. It refers to changes in sweat gland activity that are reflective of the intensity of our emotional arousal. In this article we discuss physiological specifics of skin conductance/resistance and how it is measured in practice. The most used application of GSR is in biofeedback methodology. Biofeedback assessment and training exactly uses skin reaction to different stimuli and aims to gain voluntary control over this autonomic response. The aim of this article is to show effectiveness of this method in paediatric practice.

Dissociative Symptoms in Bipolar Disorder: Impact on Clinical Course and Treatment Response

Background: Dissociative symptoms are under recognized and scarcely studied by clinicians and researchers in patients with bipolar disorder (BD). We examined the relationship between dissociative symptoms and the psychotic features in patients with BD and assessed clinical and socio-demographic characteristics more frequently associated with dissociative symptoms and treatment response. Methods: Participants were 100 adult outpatients with BD. They were screened with semi-structured interview to collect socio-demographic and clinical characteristics; the Dissociative Experiences Scale-II (DES-II) and the ALDA scale were used to assess dissociative psychopathologies and response to treatment with mood stabilizers, respectively. Results: DES score (mean 31.7 ± 21.7) correlated with clinical variables, BD features, and course of illness. Psychotic symptoms, mixed features, and previous suicide attempts significantly predicted DES score [F _{(3, 47)} = 39.880, p < 0.001, R ² corrected = 0.713]. Dissociative symptoms were inversely correlated with poor response to treatment (r = -0.593; p < 0.001). Limitations: Cross-sectional design with a small sample and backward clinical assessment of psychotic symptoms. Conclusions: Dissociative phenomena are closely related to the presence of psychotic symptoms, mixed features, and previous suicide attempts in BD, especially in BD-I. Given the close association between dissociative and psychotic symptoms, this association could represent a diagnostic indicator of BD-I that may guide the clinician to plan the most appropriate treatment.

Symptoms of depersonalisation/derealisation disorder as measured by brain electrical activity: A systematic review

Depersonalisation/derealisation disorder (DPD) refers to frequent and persistent detachment from bodily self and disengagement from the outside world. As a dissociative disorder, DPD affects 1-2 % of the population, but takes 7-12 years on average to be accurately diagnosed. In this systematic review, we comprehensively describe research targeting the neural correlates of core DPD symptoms, covering publications between 1992 and 2020 that have used electrophysiological techniques. The aim was to investigate the diagnostic potential of these relatively inexpensive and convenient neuroimaging tools. We review the EEG power spectrum, components of the event-related potential (ERP), as well as vestibular and heartbeat evoked potentials as likely electrophysiological biomarkers to study DPD symptoms. We argue that acute anxiety- or trauma-related impairments in the integration of interoceptive and exteroceptive signals play a key role in the formation of DPD symptoms, and that future research needs analysis methods that can take this integration into account. We suggest tools for prospective studies of electrophysiological DPD biomarkers, which are urgently needed to fully develop their diagnostic potential.

Levels of Depersonalization and Derealization Reported by Recovered and Non-recovered Borderline Patients Over 20 Years of Prospective Follow-up

Borderline personality disorder (BPD) is a serious psychiatric illness, and it is often associated with dissociative symptoms. The purpose of this study was to assess the course of depersonalization and derealization symptoms in recovered and non-recovered borderline patients over 20 years of prospective follow-up. The Dysphoric Affect Scale (DAS) - a 50-item self-report measure was administered to 290 borderline inpatients at baseline, and the remaining participants (85%) at 10 follow-up interviews conducted over 20 years. The level of depersonalization and derealization experienced by borderline patients was assessed using three items (feeling unreal, feeling completely numb, and feeling like people and things aren't real) from the DAS. The patients who recovered from BPD reported significantly lower scores in all three inner states (62 - 63%) at baseline compared to those patients who did not recover. Furthermore, scores of recovered and non-recovered groups decreased significantly in all three inner states studied over 20 years of prospective follow-up. Overall, these results suggest that the severity of depersonalization and derealization symptoms decreased significantly over 20 years of prospective follow-up and had a strong association with BPD recovery status.

Dissociative symptoms as measured by the Cambridge Depersonalization Scale in patients with a bipolar disorder

BACKGROUND

The Cambridge Depersonalization Scale (CDS) characterizes the quality, frequency, and duration of dissociative symptoms. While the psychometric properties of the CDS have been evaluated in primary dissociative disorder, this has been insufficiently addressed among other psychiatric patient groups such as patients with a bipolar disorder (BD).

METHODS

Outpatients with variable mood (n = 73) responded to a survey that assessed dissociative symptoms and other characteristics. We used factor analysis and McDonald's omega to evaluate psychometric properties of the CDS, and correlations with other characteristics.

RESULTS

Previously suggested multifactorial models of the CDS were not supported, but the single-dimensional model fit both dichotomized (p = 0.31, CFI = 0.99, RMSEA = 0.02, ECV 70%) and trichotomized CDS responses (p = 0.06, CFI = 0.96, RMSEA = 0.04, ECV 47%). The CDS showed high internal consistency (ω = 0.96). CDS factor scores correlated with symptom severity on the Quick Inventory for Depressive Symptoms (QIDS-SR-16) (ρ = 0.59), the Social Phobia Inventory (ρ = 0.52), the American Association of Psychiatry Severity measure for Panic Disorders (ρ = 0.46), the Childhood Trauma Questionnaire (ρ = 0.44), and the Trauma Screening Questionnaire (ρ = 0.53). Two abbreviated versions of the CDS, retaining the best 14 or 7 items were proposed.

LIMITATIONS

The sample size remained moderate.

CONCLUSIONS

The CDS is a psychometrically sound, unidimensional measure with clinical impact to detect and characterize dissociative symptoms in BD patients. Establishing the reliability and validity of the abbreviated scales for screening necessitates further study.

Symptom profile and diagnostic utility of depersonalization-derealization disorder: A retrospective critical review from India

BACKGROUND

Depersonalization and derealization (DPDR) syndrome results from complex interwoven sensory motor experiences seen across psychiatric disorders. There is sparse literature from India on DPDR symptoms, their clinical and research utility. This study focuses frequency of coding the diagnosis of DPDR (ICD-10) and critical discussion about its clinical and research utility.

METHODS

A retrospective review of case files coded under ICD code F48.1 was carried out for 10 years and details were systematically analyzed for age, gender, duration, phenomenology, comorbid diagnosis, and pharmacological treatment.

RESULTS

Fourteen patients received the diagnosis of DPDR. Mean duration of DPDR syndrome was 6 years (standard deviation [SD] = 2.2) while mean age of presentation to hospital was 24 years (SD = 2.5). Tactile imagery (50%), self-environmental integration (42%), and dream-reality integration (28%) were the major themes. Selective serotonin reuptake inhibitors were used as primary medication for 65% of patients.

CONCLUSION

Isolated DPDR syndrome has been diagnosed very rarely in recent past. Reasons may include ignoring the comorbid DPDR coding, inability to articulate DPDR symptoms, inadequate documentation and misinterpretation of symptoms or actually less prevalence of DPDR syndrome in India. Considering scanty literature on DPDR as a primary diagnosis, more studies are required to identify the actual prevalence and coding of DPDR in future.

Depersonalization, adversity, emotionality, and coping with stressful situations

Depersonalization is defined as persistent or recurrent episodes of feeling detached or estranged from a sense of self and the world. This study addressed the primary question: Do nonclinical individuals who endorse high symptomatic depersonalization have inherently more intense emotional responses, along with more childhood adversity and past trauma? In this IRB approved study, participants who met clinical levels of depersonalization (n = 43, 16.3%) were compared to a group without clinical levels of depersonalization (n = 221, 83.7%). Adverse childhood experiences, adult traumatic events, emotional overexcitability, coping strategies under stress, and anxiety were examined in both groups. The variables to assess depersonalization severity included the Dissociative Experience Scale-II, Cambridge Depersonalization Scale, and Multiscale Dissociation Inventory. The results indicated that clinical levels of depersonalization were identified in 16.3% of the sample. The high depersonalization group had significantly more adverse childhood experiences, in particular, emotional abuse and neglect. They also experienced more adult traumatic events, higher levels of anxiety, more emotional overexcitability, and they employed a less adaptive emotion-oriented coping strategy under stress. It is recommended that treating depersonalization symptoms should include examining childhood adversity, especially emotional abuse and neglect. Based on study findings, emotion regulation skills should be promoted to help individuals with elevated depersonalization manage their emotion-oriented coping strategies, anxiety, and emotional overexcitability.

A brief CBT intervention for depersonalisation/derealisation in psychosis: study protocol for a feasibility randomised controlled trial

BACKGROUND

Depersonalisation is the experience of being detached or disconnected from one's experience. Studies suggest that clinically significant levels of depersonalisation are common in individuals who have psychotic symptoms and are associated with increased impairment. However, to date, there have been no studies that have investigated an intervention designed to target clinically significant depersonalisation in such patient groups. This study aims to determine the feasibility and acceptability of a brief intervention targeting clinically significant depersonalisation in those who also have current psychotic symptoms.

METHODS/DESIGN

The feasibility of delivering six sessions of cognitive behavioural therapy for depersonalisation in psychosis patients will be evaluated using a single-blinded randomised controlled trial with a treatment as usual control condition. Participants will be assessed at baseline and then randomised to either the treatment or control arm. Participants randomised to the treatment arm will be offered six sessions of individual cognitive behavioural therapy delivered over a maximum of 10 weeks. Therapy will focus on an individualised shared formulation of depersonalisation experiences and behavioural, cognitive, emotional regulation and thinking process strategies to decrease distress associated with depersonalisation. Participants will be assessed again at a 10-week (post-randomisation) follow-up assessment. The primary outcomes of interest will be those assessing the feasibility and acceptability of the intervention including rates of referral, eligibility and acceptance to participate; attendance at therapy sessions and completion of homework tasks; satisfaction with the intervention; maintenance of blinding; and therapist competence. Secondary outcomes will be data on clinical outcome measures of depersonalisation and positive symptoms of psychosis, anxiety, depression and post-traumatic stress.

DISCUSSION

This study will determine the feasibility of delivering six sessions of cognitive behavioural therapy for individuals with current psychotic symptoms who also experience clinically significant levels of depersonalisation. The results will provide information to inform a larger randomised trial to assess intervention efficacy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02427542.

Cardiac modulation of startle is altered in depersonalization-/derealization disorder: Evidence for impaired brainstem representation of baro-afferent neural traffic

Patients with depersonalization-/derealization disorder (DPD) show altered heartbeat-evoked brain potentials, which are considered psychophysiological indicators of cortical representation of visceral-afferent neural signals. The aim of the current investigation was to clarify whether the impaired CNS representation of visceral-afferent neural signals in DPD is restricted to the cortical level or is also present in sub-cortical structures. We used cardiac modulation of startle (CMS) to assess baro-afferent signal transmission at brainstem level in 22 DPD and 23 healthy control individuals. The CMS paradigm involved acoustic startle stimuli (105dB(A), 50ms) elicited 0, 100, 200, 300, 400 and 500ms after a cardiac R-wave. In healthy control individuals, we observed lower startle responses at 100 and 300ms than at 0 and 400ms after an R-wave. In DPD patients, no effect of the cardiac cycle on startle response magnitude was found. We conclude that the representation of visceral-afferent neural signals at brainstem level may be deficient in DPD. This effect may be due to increased peripheral sympathetic tone or to dysregulated signal processing at brainstem level.

Ventrolateral prefrontal cortex repetitive transcranial magnetic stimulation in the treatment of depersonalization disorder: A consecutive case series

Case reports and an open trial have reported promising responses to repetitive transcranial magnetic stimulation (rTMS) to prefrontal and temporo-parietal sites in patients with depersonalization disorder (DPD). We recently showed that a single session of rTMS to the ventrolateral prefrontal cortex (VLPFC) was associated with a reduction in symptoms and increase in physiological arousal. Seven patients with medication-resistant DSM-IV DPD received up to 20 sessions of right-sided rTMS to the VLPFC for 10 weeks. Stimulation was guided using neuronavigation software based on participants' individual structural MRIs, and delivered at 110% of resting motor threshold. A session consisted of 1Hz repetitive TMS for 15min. The primary outcome measure was reduction in depersonalization symptoms on the Cambridge Depersonalization Scale (CDS). Secondary outcomes included scores on the Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). 20 sessions of rTMS treatment to right VLPFC significantly reduced scores on the CDS by on average 44% (range 2-83.5%). Two patients could be classified as "full responders", four as "partial" and one a non-responder. Response usually occurred within the first 6 sessions. There were no significant adverse events. A randomized controlled clinical trial of VLPFC rTMS for DPD is warranted.

A case series of 223 patients with depersonalization-derealization syndrome

BACKGROUND

Depersonalization-derealization syndrome (DDS) is an underdiagnosed and underresearched clinical phenomenon. In Germany, its administrative prevalence is far below the threshold for orphan diseases, although according to epidemiological surveys the diagnosis should be comparable frequent as anorexia nervosa for instance. Against this background, we carried out a large comprehensive survey of a DDS series in a tertiary mental health center with a specialized depersonalization-derealization clinic. To reveal differential characteristics, we compared the DDS patients, who consulted the specialized depersonalization-derealization clinic, with a group of patients with depressive disorders without comorbid DDS from the regular outpatient clinic of the mental health center.

METHODS

The sample comprised 223 patients with a diagnosis of depersonalization-derealization-syndrome and 1129 patients with a depressive disorder but without a comorbid diagnosis of DDS. DDS patients were described and compared with depressive outpatients in terms of sociodemographic characteristics, treatment history, treatment wishes, clinical symptomatology, prevailing psychosocial stressors, family history of common mental disorders and history of childhood trauma.

RESULTS

Despite the high comorbidity of DDS patients with depressive disorders and comparable burden with symptoms of depression and anxiety, the clinical picture and course of both patient groups differed strongly. DDS patients were younger, had a significant preponderance of male sex, longer disease duration and an earlier age of onset, a higher education but were more often unemployed. They tended to show more severe functional impairment. They had higher rates of previous or current mental health care utilization. Nearly all DDS patients endorsed the wish for a symptom specific counseling and 70.7 % were interested in the internet-based treatment of their problems. DDS patients had lower levels of self-rated traumatic childhood experiences and current psychosocial stressors. However, they reported a family history of anxiety disorders more often.

CONCLUSION

In consideration of the selection bias of this study, this case series supports the view that the course of the DDS tends to be long-lasting. DDS patients are severely impaired, utilizing mental health care to a high degree, which nevertheless might not meet their treatment needs, as patients strongly opt for obtaining disorder specific counseling. In view of the size of the problem, more research on the disorder, its course and its optimal treatment is urgently required.

Early-life experiences and the development of adult diseases with a focus on mental illness: The Human Birth Theory

In mammals, early adverse experiences, including mother-pup interactions, shape the response of an individual to chronic stress or to stress-related diseases during adult life. This has led to the elaboration of the theory of the developmental origins of health and disease, in particular adult diseases such as cardiovascular and metabolic disorders. In addition, in humans, as stated by Massimo Fagioli's Human Birth Theory, birth is healthy and equal for all individuals, so that mental illness develop exclusively in the postnatal period because of the quality of the relationship in the first year of life. Thus, this review focuses on the importance of programming during the early developmental period on the manifestation of adult diseases in both animal models and humans. Considering the obvious differences between animals and humans we cannot systematically move from animal models to humans. Consequently, in the first part of this review, we will discuss how animal models can be used to dissect the influence of adverse events occurring during the prenatal and postnatal periods on the developmental trajectories of the offspring, and in the second part, we will discuss the role of postnatal critical periods on the development of mental diseases in humans. Epigenetic mechanisms that cause reversible modifications in gene expression, driving the development of a pathological phenotype in response to a negative early postnatal environment, may lie at the core of this programming, thereby providing potential new therapeutic targets. The concept of the Human Birth Theory leads to a comprehension of the mental illness as a pathology of the human relationship immediately after birth and during the first year of life.

Altered patterns of heartbeat-evoked potentials in depersonalization/derealization disorder: neurophysiological evidence for impaired cortical representation of bodily signals

OBJECTIVE

Core features of depersonalization/derealization disorder (DPD) are emotional numbing and feelings of disembodiment. Although there are several neurophysiological findings supporting subjective emotional numbing, the psychobiology of disembodiment remains unclear.

METHODS

Heartbeat-evoked potentials (HEPs), which are considered psychophysiological indicators for the cortical representation of afferent signals originating from the cardiovascular system, were assessed in 23 patients with DPD and 24 healthy control individuals during rest and while performing a heartbeat perception task.

RESULTS

Absolute HEP amplitudes did not differ between groups. Nevertheless, healthy individuals showed higher HEPs during the heartbeat perception task than during rest, whereas no such effect was found in patients with DPD (p = .031). Patients with DPD had higher total levels of salivary α-amylase than did healthy individuals (9626.6 [8200.0] versus 5344.3 [3745.8] kU min/l; p = .029), but there were no group differences in cardiovascular measures (heart rate = 76.2 [10.1] versus 74.3 [7.5] beats/min, p = .60; normalized low-frequency heart rate variability = 0.63 [0.15] versus 0.56 [0.15] normalized units, p = .099; low frequency/high frequency ratio = 249.3 [242.7] versus 164.8 [108.8], p = .10), salivary cortisol (57.5 [46.7] versus 55.1 [43.6] nmol min/l, p = .86), or cortisone levels (593.2 [260.3] versus 543.8 [257.1] nmol min/l, p = .52).

CONCLUSIONS

These results suggest altered cortical representation of afferent signals originating from the cardiovascular system in patients with DPD, which may be associated with higher sympathetic tone. These findings may reflect difficulties of patients with DPD to attend to their actual bodily experiences.

Prevalence and correlates of depersonalization in students aged 12-18 years in Germany

BACKGROUND

Depersonalization (DP) involves unpleasant experiences of detachment from one's sense of self or unreality in the environment. DP may occur in a broad range of conditions, among healthy persons due to sleep loss, drug induced, secondary to anxiety disorders or primary in depersonalization disorder. Although DP has an early age of onset, little is known about the prevalence and correlates of DP among adolescents.

METHODS

Between January and June 2011, we conducted a questionnaire-based representative survey of pupils aged 12-18 years in the federal state Rhineland-Palatinate of Germany. The final sample comprised 3,809 pupils. We analyzed the prevalence of depersonalization and its correlates regarding sociodemographic characteristics, substance abuse, global mental distress and resilience factors.

RESULTS

One-third of the sample showed severe global mental distress, and 11.9 % were in the range of clinically significant depersonalization. Depersonalized students were less often living with both parents (67.3 vs. 75.7 %), came more often from an disadvantaged socioeconomic background, had a very severe level of global mental distress (comparable to psychiatric inpatients), were more often smoking and abusing cannabis and they suffered from specific impairments regarding social insecurity, global self-efficacy and active coping abilities.

CONCLUSIONS

Experiences of depersonalization were very common among adolescents and may indicate an increased risk for poor academic achievement and mental health in the long term. Prospective studies are needed to investigate the course and clinical relevance of depersonalization for the development of the adolescents.

Depersonalization: physiological or pathological in adolescents?

BACKGORUND

This study analyzed the presence of DP symptoms in a sample of both psychiatric patients and normal subjects, addressing the issue of DP symptoms in adolescence.

METHODS

A total of 267 subjects (149 patients and 118 healthy controls) aged between 14 and 65 years, were assessed by means of CDS, the SCID-I and the K-SADS. The sample was then divided into two subsamples with a cut-off age of 21 years.

RESULTS

As expected CDS score was significantly higher in the patient group compared to the healthy control group. As for the age issue, among patients no statistical difference was found comparing subjects over and under 21 years, whereas in the sample of healthy controls, subjects under 21 years reported CDS scores significantly higher.

CONCLUSIONS

While in adults DP symptoms are frequently associated with mental disorders, in adolescents they could be considered as a quasi-physiological phenomenon.

Abnormal cardiovascular sympathetic and parasympathetic responses to physical and emotional stimuli in depersonalization disorder

Background

Depersonalization disorder (DPD) is characterized by a subjective sense of unreality, disembodiment, emotional numbing and reduced psychogenic (sudomotor) sympathoexcitation.

Aims

Three related experiments utilized escalating physical and emotional challenges in 14 DPD participants and 16 controls aimed to elucidate (i) whether the cardiovascular sympathetic (SNS) and parasympathetic (PNS) nervous systems are implicated in DPD pathophysiology and (ii) if possible, to determine whether the blunted sympathoexcitation in DPD is peripherally or centrally mediated.

Method

Participants completed the Beck Anxiety Inventory (BAI), Dissociative Experience Scale (DES), and Cambridge Depersonalization Scale (CDS). Study I recorded heart rate (HR) and blood pressure (BP) during 5 min supine baseline, 3 min sustained handgrip (HG), 3 min cold pressor (CP) and 5 min 60° head-up tilt (HUT). In study II, HR, BP, and heart rate variability (HRV) were recorded during 5 min simultaneous 60° HUT and continuous presentation of unpleasant images (5 s per image). Study III examined HR and BP orienting responses (ORs) to simultaneous 60° HUT and pseudorandom presentation of unpleasant, neutral and pleasant images (5 s per image 3 min 25 s). OR data was grouped by image valence post hoc.

Results

DPD BAI (p = 0.0004), DES (p = 0.0002), and CDS (p ≤ 0.0001) scores were higher than controls. The DPD group produced diminished diastolic BP (DBP) (p = 0.045) increases to HG. Other indices were comparable between groups. DPD participants produced diminished systolic BP (SBP) (p = 0.003) and DBP (p = 0.002) increases, but greater (p = 0.004) HR increases to CP. In study II, DPD high frequency HRV (HF-HRV)—indicating parasympathetic vagal activity–was reduced (p = 0.029). In study III, DPD DBP was higher throughout the 5 s duration of HUT/pseudorandom unpleasant image presentation (1 s, p = 0.002, 2 s p = 0.033, 3 s p = 0.001, 4 s p = 0.009, 5 s p = 0.029).

Conclusions

Study I's BP pressor data supports previous findings of suppressed sympathoexcitation in DPD. The greater HR increases to CP, decreased HF-HRV in study II, and increased DBP during unpleasant ORs in study III implicates the SNS and PNS in DPD pathophysiology. These studies suggest the cardiovascular autonomic dysregulation in DPD is likely to be centrally-mediated.

Neurovisceral phenotypes in the expression of psychiatric symptoms

This review explores the proposal that vulnerability to psychological symptoms, particularly anxiety, originates in constitutional differences in the control of bodily state, exemplified by a set of conditions that include Joint Hypermobility, Postural Tachycardia Syndrome and Vasovagal Syncope. Research is revealing how brain-body mechanisms underlie individual differences in psychophysiological reactivity that can be important for predicting, stratifying and treating individuals with anxiety disorders and related conditions. One common constitutional difference is Joint Hypermobility, in which there is an increased range of joint movement as a result of a variant of collagen. Joint hypermobility is over-represented in people with anxiety, mood and neurodevelopmental disorders. It is also linked to stress-sensitive medical conditions such as irritable bowel syndrome, chronic fatigue syndrome and fibromyalgia. Structural differences in “emotional” brain regions are reported in hypermobile individuals, and many people with joint hypermobility manifest autonomic abnormalities, typically Postural Tachycardia Syndrome. Enhanced heart rate reactivity during postural change and as recently recognized factors causing vasodilatation (as noted post-prandially, post-exertion and with heat) is characteristic of Postural Tachycardia Syndrome, and there is a phenomenological overlap with anxiety disorders, which may be partially accounted for by exaggerated neural reactivity within ventromedial prefrontal cortex. People who experience Vasovagal Syncope, a heritable tendency to fainting induced by emotional challenges (and needle/blood phobia), are also more vulnerable to anxiety disorders. Neuroimaging implicates brainstem differences in vulnerability to faints, yet the structural integrity of the caudate nucleus appears important for the control of fainting frequency in relation to parasympathetic tone and anxiety. Together there is clinical and neuroanatomical evidence to show that common constitutional differences affecting autonomic responsivity are linked to psychiatric symptoms, notably anxiety.

Dissociative disorders: between neurosis and psychosis

Dissociative disorders are a set of disorders defined by a disturbance affecting functions that are normally integrated with a prevalence of 2.4 percent in industrialised countries. These disorders are often poorly diagnosed or misdiagnosed because of sharing common clinical features with psychotic disorders, but requiring a very different trajectory of care. Repeated clinical situations in a crisis centre in Geneva provided us with a critical overview of current evidence of knowledge in clinical and etiopathological field about dissociative disorders. Because of their multiple expressions and the overlap with psychotic disorders, we focused on the clinical aspects using three different situations to better understand their specificity and to extend our thinking to the relevance of terms “neurosis” and “psychosis.” Finally, we hope that this work might help physicians and psychiatrists to become more aware of this complex set of disorders while making a diagnosis.

How do you feel when you can't feel your body? Interoception, functional connectivity and emotional processing in depersonalization-derealization disorder

Depersonalization-Derealization Disorder (DD) typically manifests as a disruption of body self-awareness. Interoception -defined as the cognitive processing of body signals- has been extensively considered as a key processing for body self-awareness. In consequence, the purpose of this study was to investigate whether there are systematic differences in interoception between a patient with DD and controls that might explain the disembodiment symptoms suffered in this disease. To assess interoception, we utilized a heartbeat detection task and measures of functional connectivity derived from fMRI networks in interoceptive/exteroceptivo/mind-wandering states. Additionally, we evaluated empathic abilities to test the association between interoception and emotional experience. The results showed patient's impaired performance in the heartbeat detection task when compared to controls. Furthermore, regarding functional connectivity, we found a lower global brain connectivity of the patient relative to controls only in the interoceptive state. He also presented a particular pattern of impairments in affective empathy. To our knowledge, this is the first experimental research that assesses the relationship between interoception and DD combining behavioral and neurobiological measures. Our results suggest that altered neural mechanisms and cognitive processes regarding body signaling might be engaged in DD phenomenology. Moreover, our study contributes experimental data to the comprehension of brain-body interactions and the emergence of self-awareness and emotional feelings.

Altered orientation of spatial attention in depersonalization disorder

Difficulties with concentration are frequent complaints of patients with depersonalization disorder (DPD). Standard neuropsychological tests suggested alterations of the attentional and perceptual systems. To investigate this, the well-validated Spatial Cueing paradigm was used with two different tasks, consisting either in the detection or in the discrimination of visual stimuli. At the start of each trial a cue indicated either the correct (valid) or the incorrect (invalid) position of the upcoming stimulus or was uninformative (neutral). Only under the condition of increased task difficulty (discrimination task) differences between DPD patients and controls were observed. DPD patients showed a smaller total attention directing effect (RT in valid vs. invalid trials) compared to healthy controls only in the discrimination condition. RT costs (i.e., prolonged RT in neutral vs. invalid trials) mainly accounted for this difference. These results indicate that DPD is associated with altered attentional mechanisms, especially with a stronger responsiveness to unexpected events. From an evolutionary perspective this may be advantageous in a dangerous environment, in daily life it may be experienced as high distractibility.

Dissociative symptoms and sleep parameters--an all-night polysomnography study in patients with insomnia

BACKGROUND

Dissociative disorders encompass a range of symptoms varying from severe absent-mindedness and memory problems to confusion about one's own identity. Recent studies suggest that these symptoms may be the by-products of a labile sleep-wake cycle.

METHODS

In the current study, we explored this issue in patients suffering from insomnia (N=46). We investigated whether these patients have raised levels of dissociative symptoms and whether these are related to objective sleep parameters. Patients stayed for at least one night in a specialized sleep clinic, while sleep EEG data were obtained. In addition, they completed self-report measures on dissociative symptoms, psychological problems, and sleep characteristics.

RESULTS

Dissociative symptom levels were elevated in patients suffering from insomnia, and were correlated with unusual sleep experiences and poor sleep quality. Longer REM sleep periods and less time spent awake during the night were predictive of dissociation.

CONCLUSIONS

This is the first study to show that insomnia patients have raised dissociative symptom levels and that their dissociative symptoms are related to objective EEG parameters. These findings are important because they may inspire sleep-related treatment methods for dissociative disorders.

Early emotional processing deficits in depersonalization: an exploration with event-related potentials in an undergraduate sample

Emotional stimuli may draw attention to such an extent that they hamper the processing of subsequent signals, a phenomenon termed emotion-induced blindness (EIB). As depersonalization is associated with self-reported attenuated emotional responses, the present study explored whether individuals scoring high on the Cambridge Depersonalization Scale (CDS; n=15) exhibit a diminished EIB effect relative to low CDS scoring individuals (n=15), and whether attentional processes reflected in event-related potentials (ERPs) are implicated in this effect. We obtained an EIB effect such that emotional distractors that preceded targets with a lag of 200ms reduced correct detection of targets. Although the magnitude of this effect was similar for high and low CDS participants, high CDS participants exhibited a significantly lower ERP amplitude at the frontal lead in the 200-300ms window than did low CDS individuals to targets that followed emotional versus neutral distractors. This latter effect was significantly related to the Alienation factor of the CDS. This pattern suggests that difficulties in the discrimination between emotional and neutral stimuli relate to the feeling of unreality in depersonalization.

Depersonalization disorder and anxiety: a special relationship?

A significant association between anxiety and depersonalization has been found in healthy controls and psychiatric patients irrespective of underlying conditions. Although patients with depersonalization disorder (DPD) often have a history of severe anxiety symptoms, clinical observations suggest that the relation between anxiety and depersonalization is complex and poorly understood. Using relevant rating scales, levels of anxiety and depersonalization were assessed in 291 consecutive DPD cases. 'High' and 'low' depersonalization groups, were compared according to anxiety severity. Correlation and multivariate regression analyses were also used to assessed the contribution of anxiety to the phenomenology and natural course of depersonalization. A low but significant association between depersonalization and anxiety (as measured by Beck's Anxiety Inventory) was only apparent in those patients with low intensity depersonalization, but not in those with severe depersonalization. Levels of anxiety did not seem to make specific contributions to the clinical features of depersonalization itself, although DPD patients with high anxiety seem characterised by additional non-specific perceptual symptoms. The presence of a 'statistical dissociation' between depersonalization and anxiety adds further evidence in favour of depersonalization disorder being an independent condition and suggests that its association with anxiety has been overemphasized.

Fragmented Sleep, Fragmented Mind

In psychopathology, dissociation typically refers to a disturbance in the normal integration of thoughts, feelings, and experiences into consciousness and memory. In this article, we review the literature on how sleep disturbances relate to dissociative symptoms and memory failure. We contend that this body of research offers a fresh perspective on dissociation. Specifically, we argue that dissociative symptoms are associated with a labile sleep–wake cycle, in which dreamlike mentation invades the waking state, produces memory failures, and fuels dissociative experiences. The research domain of sleep and dissociation can accommodate the dominant idea in the clinical literature that trauma is the distal cause of dissociation, and it holds substantial promise to inspire new treatments for dissociative symptoms (e.g., interventions that focus on normalization of the sleep-wake cycle). We conclude with worthwhile paths for further investigations and suggest that the sleep–dissociation approach may help reconcile competing interpretations of dissociative symptoms.