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World Journal of Psychiatry Oct 2019Dissociation, which is defined as the failure to associate consciousness, memory, identity, emotion, perception, body representation, motor control, and behavior into an...
BACKGROUND
Dissociation, which is defined as the failure to associate consciousness, memory, identity, emotion, perception, body representation, motor control, and behavior into an integrated whole, has long been assumed to be generated by trauma. If dissociation is a product of trauma exposure, then dissociation would be a major mental health outcome observed in studies of disaster survivors. Although some studies have examined dissociation in disasters, no systematic literature reviews have been conducted to date on the topic.
AIM
To systematically evaluate the literature on the association between disaster and dissociation to determine the prevalence and incidence of dissociation after exposure to disaster and further examine their relationship.
METHODS
EMBASE, Medline, and PsychINFO were searched from inception to January 1, 2019 to identify studies examining dissociative disorders or symptoms related to a disaster in adult or child disaster survivors and disaster responders. Studies of military conflicts and war, articles not in English, and those with samples of 30 or more participants were excluded. Search terms used were "disaster*" and dissociation ("dissociat*," "multiple personality," "fugue," "psychogenic amnesia," "derealization," and "depersonalization"). Reference lists of identified articles were scrutinized to identify studies for additional articles.
RESULTS
The final number of articles in the review was 53, including 36 articles with samples of adults aged 18 and above, 5 of children/adolescents under age 18, and 12 of disaster workers. Included articles studied several types of disasters that occurred between 1989 and 2017, more than one-third (38%) from the United States. Only two studies had a primary aim to investigate dissociation in relation to disaster and none reported data on dissociative disorders. All of the studies used self-report symptom scales; none used structured interviews providing full diagnostic assessment of dissociative disorders or other psychopathology. Several studies mixed exposed and unexposed samples or did not differentiate outcomes between exposure groups. Studies examining associations between dissociation and disaster exposure have been inconclusive. The majority (75%) of the studies compared dissociation with posttraumatic stress, with inconsistent findings. Dissociation was found to be associated with a wide range of other psychiatric disorders, symptoms, and negative emotional, cognitive, and functional states.
CONCLUSION
The studies reviewed had serious methodological limitations including problems with measurement of psychopathology, sampling, and generation of unwarranted conclusions, precluding conclusions that dissociation is an established outcome of disaster.
PubMed: 31649861
DOI: 10.5498/wjp.v9.i6.83 -
Schizophrenia Bulletin Jan 2017Schizophrenia spectrum disorders (SSDs) and dissociative disorders (DDs) are described in the fifth edition of the Diagnostic and Statistical Manual for Mental Disorders... (Review)
Review
Schizophrenia spectrum disorders (SSDs) and dissociative disorders (DDs) are described in the fifth edition of the Diagnostic and Statistical Manual for Mental Disorders (DSM-5) and tenth edition of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) as 2 categorically distinct diagnostic categories. However, several studies indicate high levels of co-occurrence between these diagnostic groups, which might be explained by overlapping symptoms. The aim of this systematic review is to provide a comprehensive overview of the research concerning overlap and differences in symptoms between schizophrenia spectrum and DDs. For this purpose the PubMed, PsycINFO, and Web of Science databases were searched for relevant literature. The literature contained a large body of evidence showing the presence of symptoms of dissociation in SSDs. Although there are quantitative differences between diagnoses, overlapping symptoms are not limited to certain domains of dissociation, nor to nonpathological forms of dissociation. In addition, dissociation seems to be related to a history of trauma in SSDs, as is also seen in DDs. There is also evidence showing that positive and negative symptoms typically associated with schizophrenia may be present in DD. Implications of these results are discussed with regard to different models of psychopathology and clinical practice.
Topics: Dissociative Disorders; Humans; Psychological Trauma; Psychotic Disorders; Schizophrenia
PubMed: 27209638
DOI: 10.1093/schbul/sbw063 -
Journal of Affective Disorders Sep 2023Patients with Post-traumatic stress disorder (PTSD) exposed to traumatic reminders show hyperreactivity in brain areas (e.g., amygdala) belonging or related to the... (Meta-Analysis)
Meta-Analysis Review
Patients with Post-traumatic stress disorder (PTSD) exposed to traumatic reminders show hyperreactivity in brain areas (e.g., amygdala) belonging or related to the Innate Alarm System (IAS), allowing the rapid processing of salient stimuli. Evidence that IAS is activated by subliminal trauma-reminders could shed a new light on the factors precipitating and perpetuating PTSD symptomatology. Thus, we systematically reviewed studies investigating neuroimaging correlates of subliminal stimulation in PTSD. Twenty-three studies were selected from the MEDLINE and Scopus® databases for a qualitative synthesis, 5 of which allowed a further meta-analysis of fMRI data. The intensity of IAS responses to subliminal trauma-related reminders ranged from a minimum in healthy controls to a maximum in the PTSD patients with the most severe (e.g., dissociative) symptoms or the least responsiveness to treatment. Comparisons with other disorders (e.g., phobias) revealed contrasting results. Our findings demonstrate the hyperactivation of areas belonging or related to IAS in response to unconscious threats that should be integrated in diagnostic as well as in therapeutic protocols.
Topics: Humans; Stress Disorders, Post-Traumatic; Subliminal Stimulation; Brain; Amygdala; Brain Mapping; Magnetic Resonance Imaging
PubMed: 37236272
DOI: 10.1016/j.jad.2023.05.047 -
Journal of Affective Disorders Apr 2017The dissociative PTSD (D-PTSD) subtype was first introduced into the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013. Prior to... (Review)
Review
BACKGROUND
The dissociative PTSD (D-PTSD) subtype was first introduced into the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013. Prior to this, studies using latent profile analysis (LPA) or latent class analysis (LCA), began to provide support for the D-PTSD construct and associated risk factors. This research is important, because dissociative symptoms in the context of PTSD may potentially interfere with treatment course or outcome. The aims of the present study were twofold: to systematically review the LCA and LPA studies investigating support for the D-PTSD construct; and to review the associated research on the risk factors or covariates of D-PTSD in the identified studies.
METHOD
Six databases (PubMed, Web of Science, Scopus, PILOTS, PsychInfo, and Embase) were systematically searched for relevant papers.
RESULTS
Eleven studies were included in the present review. The majority of the studies were supportive of the D-PTSD subtype; primarily characterized by depersonalization and derealization. Several covariates of the D-PTSD subtype have been investigated with mixed results.
LIMITATIONS
Many limitations relate to the state of the current literature, including a small number of studies, the use of self-report measurements of PTSD, and heterogeneity across the samples in investigated covariates.
CONCLUSION
The results were overall supportive of the D-PTSD construct. Future research on D-PTSD and associated risk factors is needed to shed light on the possibilities of facilitating preventive actions, screening, and implications on treatment effects.
Topics: Depersonalization; Diagnostic and Statistical Manual of Mental Disorders; Dissociative Disorders; Humans; Risk Factors; Self Report; Stress Disorders, Post-Traumatic
PubMed: 28192736
DOI: 10.1016/j.jad.2017.02.004 -
Consciousness and Cognition Mar 2023Strange face illusions describe a range of visual apparitions that occur when an observer gazes at their image reflected in a mirror or at another person's face in a... (Review)
Review
BACKGROUND
Strange face illusions describe a range of visual apparitions that occur when an observer gazes at their image reflected in a mirror or at another person's face in a dimly lit room. The illusory effects range from mild alterations in colour, or contrast, to the perception of distorted facial features, or new strange faces.The current review critically evaluates studies investigating strange face illusions, their methodological quality, and existing interpretations.
METHOD
Searches conducted using Scopus, PubMed, ScienceDirect and the grey literature until June 2022 identified 21 studies (N = 1,132; healthy participants n = 1,042; clinical participants n = 90) meeting the inclusion criteria (i.e., providing new empirical evidence relating to strange face illusions). The total sample had a mean age of 28.3 years (SD = 10.31) and two thirds (67 %) of participants tested to date are female. Results are reported using the Preferred Reporting Items for Systematic Reviews and meta-Analyses (PRISMA) guidelines. The review was preregistered at the Open Science Framework (OSF: https://osf.io/ek48d).
RESULTS
Pooling data across studies, illusory new strange faces are experienced by 58% (95%CI 48 to 68) of nonclinical participants. Study quality as assessed by the Appraisal Tool for Cross-Sectional Studies (AXIS) revealed that 3/21 (14.28%) studies were rated as high, 9/21 (42.86%) as moderate and 9/21 (42.86%) as low quality. Whilst the items relating specifically to reporting quality scored quite highly, those relating to study design and possible biases were lower and more variable. Overall, study quality accounted for 87% of the variance in reporting rates for strange faces, with higher quality being associated with lower illusion rates. The prevalence of illusions was also significantly greater in samples that were older, had higher proportions of female participants and for the interpersonal dyad (IGDT) compared to the mirror gaze paradigm (MGT). The moderating impact of study quality persisted in a multiple meta-regression involving participant age, paradigm type (IGDT vs MGT) and level of feature distortion. Our review point to the importance of reduced light levels, face stimuli and prolonged eye fixation for strange face illusions to emerge.
CONCLUSION
Strange face illusions reliably occur in both mirror-gazing and interpersonal gazing dyad paradigms. Further research of higher quality is required to establish the prevalence and particularly, the mechanisms underpinning strange face illusions.
Topics: Humans; Female; Adult; Male; Illusions; Cross-Sectional Studies; Face; Fixation, Ocular; Dissociative Disorders
PubMed: 36764163
DOI: 10.1016/j.concog.2023.103480 -
CNS Drugs Jan 2016Several case reports and epidemiological studies have raised concern about the abuse potential of pregabalin, the use of which has increased substantially over the last... (Review)
Review
BACKGROUND
Several case reports and epidemiological studies have raised concern about the abuse potential of pregabalin, the use of which has increased substantially over the last decade. Pregabalin is, in some cases, used for recreational purposes and it has incurred attention among drug abusers for causing euphoric and dissociative effects when taken in doses exceeding normal therapeutic dosages or used by alternative routes of administration, such as nasal insufflation or venous injection. The magnitude of the abuse potential and the mechanism behind it are not fully known.
OBJECTIVE
The aim of this study was to present a systematic review of the data concerning the abuse potential of pregabalin.
METHODS
We performed a systematic literature search and reviewed the preclinical, clinical and epidemiological data on the abuse potential of pregabalin.
RESULTS
We included preclinical (n = 17), clinical (n = 19) and epidemiological (n = 13) studies addressing the abuse potential of pregabalin. We also reviewed case reports (n = 9) concerning abuse of pregabalin. The preclinical studies indicated that pregabalin possesses modulatory effects on the GABA and glutamate systems, leaving room for an abuse potential. Further, clinical studies reported euphoria as a frequent side effect in patients treated with pregabalin. The majority of case reports concerning abuse of pregabalin involved patients with a history of substance abuse and, similarly, epidemiological studies found evidence of abuse, especially among opiate abusers.
CONCLUSIONS
Overall, the available literature suggests an important clinical abuse potential of pregabalin and prescribers should pay attention to signs of abuse, especially in patients with a history of substance abuse.
Topics: Animals; Clinical Trials as Topic; Drug Evaluation, Preclinical; Euphoria; Humans; Illicit Drugs; Pregabalin; Prescription Drug Misuse; Substance-Related Disorders
PubMed: 26767525
DOI: 10.1007/s40263-015-0303-6 -
European Journal of Psychotraumatology 2022Neurophysiological models link dissociation (e.g. feeling detached during or after a traumatic event) to hypoarousal. It is currently assumed that the initial passive... (Review)
Review
Trauma-related dissociation and the autonomic nervous system: a systematic literature review of psychophysiological correlates of dissociative experiencing in PTSD patients.
Neurophysiological models link dissociation (e.g. feeling detached during or after a traumatic event) to hypoarousal. It is currently assumed that the initial passive reaction to a threat may coincide with a blunted autonomic response, which constitutes the dissociative subtype of post-traumatic stress disorder (PTSD). Within this systematic review we summarize research which evaluates autonomic nervous system activation (e.g. heart rate, blood pressure) and dissociation in PTSD patients to discern the validity of current neurophysiological models of trauma-related hypoarousal. Of 553 screened articles, 28 studies ( = 1300 subjects) investigating the physiological response to stress provocation or trauma-related interventions were included in the final analysis. No clear trend exists across all measured physiological markers in trauma-related dissociation. Extracted results are inconsistent, in part due to high heterogeneity in experimental methodology. The current review is unable to provide robust evidence that peri- and post-traumatic dissociation are associated with hypoarousal, questioning the validity of distinct psychophysiological profiles in PTSD.
Topics: Humans; Stress Disorders, Post-Traumatic; Dissociative Disorders; Autonomic Nervous System; Heart Rate; Psychophysiology
PubMed: 36340007
DOI: 10.1080/20008066.2022.2132599 -
Journal of Affective Disorders Jun 2024Electrophysiologic measures provide an opportunity to inform mechanistic models and possibly biomarker prediction of response. Serotonergic psychedelics (SPs) (i.e.,... (Review)
Review
Spectral signatures of psilocybin, lysergic acid diethylamide (LSD) and ketamine in healthy volunteers and persons with major depressive disorder and treatment-resistant depression: A systematic review.
BACKGROUND
Electrophysiologic measures provide an opportunity to inform mechanistic models and possibly biomarker prediction of response. Serotonergic psychedelics (SPs) (i.e., psilocybin, lysergic acid diethylamide (LSD)) and ketamine represent new investigational and established treatments in mood disorders respectively. There is a need to better characterize the mechanism of action of these agents.
METHODS
We conducted a systematic review investigating the spectral signatures of psilocybin, LSD, and ketamine in persons with major depressive disorder (MDD), treatment-resistant depression (TRD), and healthy controls.
RESULTS
Ketamine and SPs are associated with increased theta power in persons with depression. Ketamine and SPs are also associated with decreased spectral power in the alpha, beta and delta bands in healthy controls and persons with depression. When administered with SPs, theta power was increased in persons with MDD when administered with SPs. Ketamine is associated with increased gamma band power in both healthy controls and persons with MDD.
LIMITATIONS
The studies included in our review were heterogeneous in their patient population, exposure, dosing of treatment and devices used to evaluate EEG and MEG signatures. Our results were extracted entirely from persons who were either healthy volunteers or persons with MDD or TRD.
CONCLUSIONS
Extant literature evaluating EEG and MEG spectral signatures indicate that ketamine and SPs have reproducible effects in keeping with disease models of network connectivity. Future research vistas should evaluate whether observed spectral signatures can guide further discovery of therapeutics within the psychedelic and dissociative classes of agents, and its prediction capability in persons treated for depression.
Topics: Humans; Psilocybin; Ketamine; Lysergic Acid Diethylamide; Depressive Disorder, Major; Depression; Healthy Volunteers; Hallucinogens
PubMed: 38570038
DOI: 10.1016/j.jad.2024.03.165 -
Trauma, Violence & Abuse Jan 2004Violent acts are sometimes committed by people who do not normally appear violent or aggressive. This simple observation and others have led some to speculate about a... (Review)
Review
Violent acts are sometimes committed by people who do not normally appear violent or aggressive. This simple observation and others have led some to speculate about a relationship between dissociation and violence. However, no systematic review of the literature has so far been published. To address this gap, studies assessing the prevalence of dissociation among violent individuals, and violence among highly dissociative persons, are reviewed. Possible links between dissociation and violent behavior are explored. It is concluded that dissociation predicts violence in a wide range of populations and may be crucial to an understanding of violent behavior. There is a clear need, however, for large scale, well-designed studies using reliable structured instruments in a number of areas reviewed. Recommendations for clinical applications include the routine screening of offenders for dissociative disorders and adequate consideration of dissociation and dissociative disorders in the development and implementation of violence treatment and prevention programs.
Topics: Aggression; Amnesia; Antisocial Personality Disorder; Crime; Criminal Psychology; Dissociative Disorders; Humans; Mental Disorders; Personality Disorders; Risk Assessment; Risk Factors; Sex Offenses; Violence
PubMed: 15006295
DOI: 10.1177/1524838003259321 -
Neuroscience and Biobehavioral Reviews Jun 2018The present review aimed to 1) identify what sleep disturbances co-occur alongside psychotic-like, dissociative and hypomanic experiences; 2) assess the strength of...
Are sleep disturbances causally linked to the presence and severity of psychotic-like, dissociative and hypomanic experiences in non-clinical populations? A systematic review.
The present review aimed to 1) identify what sleep disturbances co-occur alongside psychotic-like, dissociative and hypomanic experiences; 2) assess the strength of potential associations between the severity of sleep disturbances and of the experiences studied; and 3) appraise evidence for a causal link. MedLine and PsycInfo were searched and 44 studies were deemed eligible. Results showed that insomnia was associated with all individual psychotic-like, dissociative and hypomanic experiences reviewed (effect size range: small-to-large). Parasomnias were associated with all psychotic-like experiences; however, there was evidence of variation in magnitude between individual experiences. An eveningness chronotype was associated with dissociative and hypomanic experiences, and circadian dysrhythmia was found alongside hypomania but not the other experiences reviewed. Finally, experimental sleep manipulation studies revealed a potential causal link between sleep loss and psychotic-like and dissociative experiences, although size and consistency of effects varied by specific experience. Future research, using experimental manipulations of sleep to address putative mechanisms, will enable questions of causality to be answered with more confidence.
Topics: Chronobiology Disorders; Humans; Psychotic Disorders; Sample Size; Sleep; Sleep Initiation and Maintenance Disorders; Sleep Wake Disorders
PubMed: 29452128
DOI: 10.1016/j.neubiorev.2018.02.008