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Journal of Personalized Medicine Aug 2022Dissociative disorders encompass loss of integration in essential functions such as memory, consciousness, perception, motor control, and identity. Nevertheless,... (Review)
Review
BACKGROUND
Dissociative disorders encompass loss of integration in essential functions such as memory, consciousness, perception, motor control, and identity. Nevertheless, neuroimaging studies, albeit scarce, have suggested the existence of particular brain activation patterns in patients belonging to this diagnostic category. The aim of this review is to identify the main functional neuroimaging correlates of dissociative disorders.
METHODS
we searched the PubMed database to identify functional neuroimaging studies conducted on subjects with a diagnosis of a dissociative disorder, following the PRISMA guidelines. In the end, we included 13 studies in this systematic review, conducted on 51 patients with dissociative identity disorder (DID), 28 subjects affected by depersonalization disorder, 24 with dissociative amnesia, and 6 with other or not specified dissociative disorders.
RESULTS
Prefrontal cortex dysfunction seems prominent. In addition, changes in the functional neural network of the caudate are related to alterations of identity state and maintenance of an altered mental status in DID. Another role in DID seems to be played by a dysfunction of the anterior cingulate gyrus. Other regions, including parietal, temporal, and insular cortices, and subcortical areas were reported to be dysfunctional in dissociative disorders.
CONCLUSIONS
Prefrontal dysfunction is frequently reported in dissociative disorders. Functional changes in other cortical and subcortical areas can be correlated with these diagnoses. Further studies are needed to clarify the neurofunctional correlations of each dissociative disorder in affected patients, in order to identify better tailored treatments.
PubMed: 36143190
DOI: 10.3390/jpm12091405 -
Neuroscience and Biobehavioral Reviews Jan 2022Dissociative disorders (DD) and conversion disorders (CD) are frequent in general and psychiatric populations. Some evidence suggest that the hypothalamic-pituitary axis... (Review)
Review
Dissociative disorders (DD) and conversion disorders (CD) are frequent in general and psychiatric populations. Some evidence suggest that the hypothalamic-pituitary axis (HPA) and autonomic nervous system (ANS) are dysregulated in both disorders. We carried out a systematic review of the literature to summarize the existing knowledge on the stress response, via HPA and/or ANS, in patients with DD, CD, or dissociative symptoms. We systematically searched Medline and Web of Science using the Medical Subject Headings related to stress axis, CD, DD, and dissociative symptoms following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results suggest that in participants without psychiatric history, high cortisol secretion is related to high dissociation scores. Conversely the stress system might be blunted in patients with post-traumatic stress disorder who develop dissociative symptoms. Stress response changes seem to be associated with the emergence and persistence of dissociative and conversion disorders. Hence, monitoring the stress response and examining closely the history of stress exposure in DD and CD should be encouraged in future larger studies.
Topics: Autonomic Nervous System; Conversion Disorder; Dissociative Disorders; Humans; Hypothalamo-Hypophyseal System; Pituitary-Adrenal System; Stress Disorders, Post-Traumatic
PubMed: 34740754
DOI: 10.1016/j.neubiorev.2021.10.049 -
General Hospital Psychiatry 2017It has been argued that the label given to unexplained neurological symptoms is an important contributor to their often poor acceptance, and there has been recent debate... (Review)
Review
OBJECTIVE
It has been argued that the label given to unexplained neurological symptoms is an important contributor to their often poor acceptance, and there has been recent debate on proposals to change the name from conversion disorder. There have been multiple studies of layperson and clinician preference and this article aimed to review these.
DESIGN
Multiple databases were searched using terms including "conversion disorder" and "terminology", and relative preferences for the terms extracted.
RESULTS
Seven articles were found which looked at clinician or layperson preferences for terminology for unexplained neurological symptoms. Most neurologists favoured terms such as "functional" and "psychogenic", while laypeople were comfortable with "functional" but viewed "psychogenic" as more offensive; "non-epileptic/organic" was relatively popular with both groups.
CONCLUSIONS
"Functional" is a term that is relatively popular with both clinicians and the public. It also meets more of the other criteria proposed for an acceptable label than other popular terms - however the views of neither psychiatrists nor actual patients with the disorder were considered.
Topics: Conversion Disorder; Humans; Terminology as Topic
PubMed: 28274339
DOI: 10.1016/j.genhosppsych.2016.12.009 -
European Journal of Psychotraumatology 2023The clinical guidelines for the treatment of dissociation focus primarily on psychotherapy. However, different psychoactive drugs are used in clinical practice. The use... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The clinical guidelines for the treatment of dissociation focus primarily on psychotherapy. However, different psychoactive drugs are used in clinical practice. The use of opioid antagonists has been proposed as a therapeutic option based on the theory that dissociation might be a phenomenon mediated by dysregulation of the endogenous opioid system.
OBJECTIVE
To review and meta-analyse the available evidence on the efficacy of the opioid antagonists naltrexone, naloxone, and nalmefene as treatments for dissociative symptoms and disorders.
METHOD
The PRISMA guidelines were followed, and this review was registered in Prospero with reference number CRD42021280976. The search was performed in the PubMed, Scopus, Web of Science, EMBASE, PsycINFO, and PubPsych databases.
RESULTS
1,798 citations were obtained. After removing duplicates and applying inclusion and exclusion criteria, we included 5 comparative studies with 9 dissociation measures that had included a total of 154 participants, of whom 134 had been treated with an opioid antagonist. The results of the meta-analysis showed a treatment effect for dissociation when using opioid antagonists [pooled = 1.46 (95% CI: 0.62-2.31)]. However, the studies we included were very heterogeneous [Q = 66.89 ( < .001)] and there may have been publication bias.
CONCLUSIONS
Although more research is needed and the results must be interpreted with caution because of the limited amount of data and heterogeneity in the studies and their methodological qualities, opioid antagonists (particularly naltrexone) are promising candidates for the treatment of dissociative symptoms and showed a moderate - large effect size in reducing these symptoms.
Topics: Humans; Narcotic Antagonists; Naltrexone; Naloxone; Dissociative Disorders
PubMed: 37860852
DOI: 10.1080/20008066.2023.2265184 -
Clinical Psychology Review Aug 2015There are an increasing number of studies exploring the association between voice-hearing (auditory verbal hallucinations) and dissociative experiences. The current... (Meta-Analysis)
Meta-Analysis Review
There are an increasing number of studies exploring the association between voice-hearing (auditory verbal hallucinations) and dissociative experiences. The current study provides a systematic literature review and meta-analytic synthesis of quantitative studies investigating the relationship between voice-hearing and dissociation. A systematic search identified and included 19 clinical studies, comprising 1620 participants, and 12 non-clinical studies, comprising 2137 participants, published between 1986 and 2014. Nineteen of these studies provided sufficient data to be included within the meta-analysis. The narrative review findings suggested that dissociative experiences may be implicated in voice-hearing, and may potentially be a mediating factor within the well-established trauma and voice-hearing relationship. Similarly, the meta-analytic findings suggested that the majority of the identified studies showed a significant positive relationship between dissociative experiences and voice-hearing. The magnitude of the summary effect was large and significant (r=.52), indicating a robust relationship between these two phenomena. However, considerable heterogeneity within the meta-analytic results and methodological limitations of the identified studies were evident, highlighting areas for future investigation. As the majority of the studies were cross-sectional by design, we recommended future research to include longitudinal designs with a view to exploring directional effects. Additionally, future studies should control for potential confounding factors. Clinical implications of the findings were also considered.
Topics: Comorbidity; Dissociative Disorders; Hallucinations; Humans
PubMed: 26117061
DOI: 10.1016/j.cpr.2015.06.004 -
Journal of Psychiatric Research Sep 2020There is currently no general agreement on how to best conceptualize dissociative symptoms and whether they share similar neural underpinnings across dissociative... (Review)
Review
INTRODUCTION
There is currently no general agreement on how to best conceptualize dissociative symptoms and whether they share similar neural underpinnings across dissociative disorders. Neuroimaging data could help elucidate these questions.
OBJECTIVES
The objective of this review is to summarize empirical evidence for neural aberrations observed in patients suffering from dissociative symptoms.
METHODS
A systematic literature review was conducted including patient cohorts diagnosed with primary dissociative disorders, post-traumatic stress disorder (PTSD), or borderline personality disorder.
RESULTS
Results from MRI studies reporting structural (gray matter and white matter) and functional (during resting-state and task-related activation) brain aberrations were extracted and integrated. In total, 33 articles were included of which 10 pertained to voxel-based morphology, 2 to diffusion tensor imaging, 10 to resting-state fMRI, and 11 to task-related fMRI. Overall findings indicated aberrations spread across diverse brain regions, especially in the temporal and frontal cortices. Patients with dissociative identity disorder and with dissociative PTSD showed more overlap in brain activation than each group showed with depersonalization/derealization disorder.
CONCLUSION
In conjunction, the results indicate that dissociative processing cannot be localized to a few distinctive brain regions but rather corresponds to differential neural signatures depending on the symptom constellation.
Topics: Brain; Diffusion Tensor Imaging; Dissociative Disorders; Gray Matter; Humans; Magnetic Resonance Imaging; Stress Disorders, Post-Traumatic
PubMed: 32480060
DOI: 10.1016/j.jpsychires.2020.05.006 -
Journal of Psychiatric Research Nov 2021Ketamine is a dissociative anesthetic used worldwide for anesthesia, pain management, treatment resistant depression (TRD) and suicidality. Predictors of antidepressant... (Review)
Review
Ketamine is a dissociative anesthetic used worldwide for anesthesia, pain management, treatment resistant depression (TRD) and suicidality. Predictors of antidepressant response and adverse effects to ketamine remain poorly understood due to contradictory results. The objective of the systematic review herein is to identify and evaluate the extant literature assessing pharmacogenomic predictors of ketamine clinical benefits and adverse effects. Electronic databases were searched from inception to July 2021 to identify relevant articles. Twelve articles involving 1,219 participants with TRD, 75 who underwent elective surgeries and received ketamine as an anesthetic, 49 with pain, and 68 healthy participants met the inclusion criteria and enrolled to this review. While identified articles reported mixed results, three predictors emerged: 1) Val66Met (rs6265) brain derived neurotrophic factor (BDNF; Met allele) was associated with reduced antidepressant and anti-suicidal effects, 2) CYP2B6*6 (e.g., CYB2B6 metabolizer) was associated with more severe dissociative effects and 3) NET allelic (rs28386840) variant were associated with greater cardiovascular complications (e.g., moderate to severe treatment emergent hypertension). Several important limitations were identified, most notably the small sample sizes and heterogeneity of study design and results. Taken together, preliminary evidence suggests the potential for pharmacogenomic testing to inform clinical practices; however, further research is needed to better determine genetic variants of greatest importance and the clinical validity of pharmacogenomics to help guide ketamine treatment planning.
PubMed: 34844049
DOI: 10.1016/j.jpsychires.2021.11.036 -
Journal of Trauma & Dissociation : the... 2023This systematic review and meta-analysis aimed to investigate the relationship between dissociation and obsessive-compulsive symptoms (OCS) and disorder (OCD).... (Meta-Analysis)
Meta-Analysis Review
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 ( = 9,438, 34.3% males). The pooled prevalence of dissociative disorders in adult samples with OCD was 8% (95% CI [3, 15], = 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 ( = .67, 95% CI [.18, 1.16], = 9). A moderate correlation between dissociative symptoms and OCS was detected ( = .43, 95% CI [.36, .51], = 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.
Topics: Adult; Male; Adolescent; Humans; Female; Obsessive-Compulsive Disorder; Prospective Studies; Comorbidity; Dissociative Disorders; Prevalence
PubMed: 36820493
DOI: 10.1080/15299732.2023.2181477 -
Clinical Psychology & Psychotherapy Sep 2023Dissociative identity disorder and depersonalization-derealization have attracted research and clinical interest, facilitating greater understanding. However, little is... (Review)
Review
BACKGROUND
Dissociative identity disorder and depersonalization-derealization have attracted research and clinical interest, facilitating greater understanding. However, little is known about the experience of multiplicity of self outside of traumagenic or illness constructs. Consequently, this systematic review explored how people identifying as having multiple selves conceptualize their experiences and identity.
METHODS
A comprehensive search of qualitative studies reporting lived experiences of multiplicity was conducted through PsycINFO, PubMed and Scopus (PROSPERO ID: CRD42021258555). Thirteen relevant studies were retrieved (N = 98, 16-64 years, conducted in the United Kingdom, the United States, Hungary and Poland).
RESULTS
Using line-by-line thematic synthesis, four analytical themes were developed: multiplicity: disorder versus experience; impact of understanding multiplicity; importance of supporting multiplicity; and continuum of experiences.
DISCUSSION
This review highlights heterogeneity within multiplicity-spectrum experiences, emphasizing the need for person-centred, individualized understanding, separate from mental health conceptualizations. Therefore, training in person-centred individualized care to promote self-concept clarity is needed across health, education and social care. This systematic review is the first to synthesize voices of people with lived experience across the multiplicity spectrum, demonstrating how qualitative research can contribute to advancing our understanding of this complex phenomena with the community, acknowledging reciprocal psychosocial impacts of multiplicity and providing valuable recommendations for services.
PubMed: 37699854
DOI: 10.1002/cpp.2910 -
Cells Feb 2022Ketamine is a rapid-acting antidepressant with proven efficacy as an add-on agent in unipolar and bipolar treatment-resistant depression. Although many studies have been... (Review)
Review
BACKGROUND AND OBJECTIVES
Ketamine is a rapid-acting antidepressant with proven efficacy as an add-on agent in unipolar and bipolar treatment-resistant depression. Although many studies have been published, there is still not enough data on the effect of ketamine in combination with other medications. Particularly interesting is the combination of ketamine and lamotrigine, and its potential role in bipolar depression. The aim of this review was to identify animal and human studies in which ketamine and lamotrigine were used together in order to find out if there is scientific ground for combining ketamine and lamotrigine in the treatment of mood disorders. Directions for future studies are presented.
MATERIALS AND METHODS
PubMed and Web of Science were searched. Preferred Reporting Items for Systematic Reviews and Meta-Analyses PRISMA 2020 methodology was applied.
RESULTS
Seventeen studies were included for review. Animal studies using models of depression suggested a synergistic effect of ketamine and lamotrigine in combination. Studies on healthy humans showed a reduction in ketamine-induced dissociative symptoms with lamotrigine pretreatment. In a study on patients with depression, ketamine and lamotrigine did not have a stronger antidepressant effect than ketamine alone, but in this study only one ketamine infusion was administered. One case series described the antidepressant and anti-suicidal effect of the combination in two bipolar patients. Available clinical studies on patients with mood disorders did not support the hypothesis that lamotrigine reduces ketamine-induced dissociative symptoms.
CONCLUSIONS
The results of the analyzed studies were not sufficient to answer any of the stated questions; however, they allowed us to delineate future research directions. The identified animal studies suggested a possible synergistic antidepressant effect of ketamine and lamotrigine. The available clinical studies were not conclusive. No controlled studies on large groups of bipolar patients with multiple ketamine infusions combined with lamotrigine treatment have been published so far. There is some evidence for the reduction of ketamine's side effects by lamotrigine, and there are reports suggesting that lamotrigine can reduce ketamine craving. More studies with follow-up are needed in order to investigate the ketamine-lamotrigine combination in bipolar patients.
Topics: Animals; Antidepressive Agents; Depression; Humans; Ketamine; Lamotrigine; Psychopharmacology
PubMed: 35203296
DOI: 10.3390/cells11040645