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Psychiatry and Clinical... Sep 2022Reduced memory specificity (i.e., overgeneral memory) is a characteristic of autobiographical memories widely studied in clinical populations, and it is explained by... (Review)
Review
BACKGROUND
Reduced memory specificity (i.e., overgeneral memory) is a characteristic of autobiographical memories widely studied in clinical populations, and it is explained by rumination, functional avoidance, and executive dysfunction. Though the relationship of autobiographical memory specificity with mood and anxiety disorders has been shown, how it relates to dissociation is not well-established. Thus, we aimed to investigate whether dissociative experiences are related to overgeneral memory while considering concurrent depression as a possible confounding factor.
METHODS
We conducted a systematic review in compliance with The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and searched PubMed and Web of Science databases using autobiograph* and dissoc* as our keywords.
RESULTS
Of the 768 studies identified, 9 studies fulfilled the inclusion criteria. A meta-regression analysis was conducted to analyze the relationship between dissociative experiences and depression scores with autobiographical memory test scores. Our research revealed that depression scores, but not dissociative experiences, are significantly related to reduced memory specificity.
CONCLUSION
While the possible overlap between dissociation and depression should be considered in the interpretation of the findings, dissociative experiences do not seem to pose vulnerability for reduced specificity of autobiographical memory. The number of studies on the topic is limited, and they do not have longitudinal follow-ups. The heterogeneous reporting of memory scores and low scores of dissociative experiences in the samples are also limitations of the existing studies.
PubMed: 38766667
DOI: 10.5152/pcp.2022.21285 -
British Journal of Clinical Pharmacology Oct 2022There is a growing interest in the psychiatric properties of the dissociative anaesthetic ketamine, as single doses have been shown to have fast-acting mood-enhancing... (Review)
Review
There is a growing interest in the psychiatric properties of the dissociative anaesthetic ketamine, as single doses have been shown to have fast-acting mood-enhancing and anxiolytic effects, which persist for up to a week after the main psychoactive symptoms have diminished. Therefore, ketamine poses potential beneficial effects in patients with refractory anxiety disorders, where other conventional anxiolytics have been ineffective. Ketamine is a noncompetitive antagonist of the N-methyl-d-aspartate (NMDA) glutamate receptor, which underlies its induction of pain relief and anaesthesia. However, the role of NMDA receptors in anxiety reduction is still relatively unknown. To fill this paucity in the literature, this systematic review assesses the evidence that ketamine significantly reduces refractory anxiety and discusses to what extent this may be mediated by NMDA receptor antagonism and other receptors. We highlight the temporary nature of the anxiolytic effects and discuss the high discrepancy among the study designs regarding many fundamental factors such as administration routes, complementary treatments and other treatments.
Topics: Anti-Anxiety Agents; Anxiety; Anxiety Disorders; Humans; Ketamine; Receptors, N-Methyl-D-Aspartate
PubMed: 35510346
DOI: 10.1111/bcp.15374 -
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 -
The Australian and New Zealand Journal... Oct 2022Borderline Personality Disorder (BPD) is frequently complicated by the presence of dissociative symptoms. Pathological dissociation is linked with earlier and more... (Review)
Review
BACKGROUND
Borderline Personality Disorder (BPD) is frequently complicated by the presence of dissociative symptoms. Pathological dissociation is linked with earlier and more severe trauma exposure, emotional dysregulation and worse treatment outcomes in Posttraumatic Stress Disorder and Dissociative Disorders, with implications for BPD.
OBJECTIVE
A systematic scoping review was conducted to assess the extent of current literature regarding the impact of dissociation on BPD and to identify knowledge gaps.
METHODS
Four electronic databases (MEDLINE, APA PsycINFO, EMBASE, CINAHL Plus) were searched, and English peer-reviewed studies with adults with BPD were included, following Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) extension for scoping reviews (PRISMA-ScR) 2018 guidelines.
RESULTS
Most of the 70 included studies were observational (98%) with first authors from Germany (59%). Overall, dissociation was associated with increased BPD symptom severity, self-harm and reduced psychotherapy treatment response; findings regarding suicide risk were mixed. Dissociation was associated with working memory and cognitive deficits, decreased pain perception, altered body ownership, no substance abuse or the abuse of sedative substances, increased fantasy proneness, personality fragmentation, fearful attachment, dream anxiety, perceived stress and altered stress responses, increased cumulative body mass index, decreased water consumption, several neurological correlates and changes in gene expression.
CONCLUSION
BPD with significant dissociative symptoms may constitute a more severe and at-risk subgroup of BPD patients. However, there are significant research gaps and methodological issues in the area, including the possibility of unrecognized Dissociative Disorders in BPD study populations confounding results. Further studies are needed to better understand the impact of dissociation on BPD course and treatment, and to clarify the most appropriate assessment tools for clinical practice. In addition, interventional studies are needed to develop dissociation-specific BPD treatments to determine whether targeting dissociation in BPD can improve treatment outcomes.
Topics: Adult; Borderline Personality Disorder; Dissociative Disorders; Humans; Hypnotics and Sedatives; Psychotherapy; Self-Injurious Behavior
PubMed: 35152771
DOI: 10.1177/00048674221077029 -
The International Journal of... Jul 2021Ketamine appears to have a therapeutic role in certain mental disorders, most notably unipolar major depressive disorder. However, its efficacy in bipolar depression is...
BACKGROUND
Ketamine appears to have a therapeutic role in certain mental disorders, most notably unipolar major depressive disorder. However, its efficacy in bipolar depression is less clear. This study aimed to assess the efficacy and tolerability of ketamine for bipolar depression.
METHODS
We conducted a systematic review of experimental studies using ketamine for the treatment of bipolar depression. We searched PubMed, MEDLINE, Embase, PsycINFO, and the Cochrane Central Register for relevant studies published since each database's inception. We synthesized evidence regarding efficacy (improvement in depression rating scores) and tolerability (adverse events, dissociation, dropouts) across studies.
RESULTS
We identified 6 studies, with 135 participants (53% female; 44.7 years; standard deviation, 11.7 years). All studies used 0.5 mg/kg of add-on intravenous racemic ketamine, with the number of doses ranging from 1 to 6; all participants continued a mood-stabilizing agent. The overall proportion achieving a response (defined as those having a reduction in their baseline depression severity of at least 50%) was 61% for those receiving ketamine and 5% for those receiving a placebo. The overall response rates varied from 52% to 80% across studies. Ketamine was reasonably well tolerated; however, 2 participants (1 receiving ketamine and 1 receiving placebo) developed manic symptoms. Some participants developed significant dissociative symptoms at the 40-minute mark following ketamine infusion in 2 trials.
CONCLUSIONS
There is some preliminary evidence supporting use of intravenous racemic ketamine to treat adults with bipolar depression. There is a need for additional studies exploring longer-term outcomes and alterative formulations of ketamine.
Topics: Bipolar Disorder; Excitatory Amino Acid Antagonists; Humans; Ketamine
PubMed: 33929489
DOI: 10.1093/ijnp/pyab023 -
AIMS Neuroscience 2021The temporal-parietal junction (TPJ) is a key structure for the embodiment, term referred to as the sense of being localized within one's physical body and is a... (Review)
Review
Targeting temporal parietal junction for assessing and treating disembodiment phenomena: a systematic review of TMS effect on depersonalization and derealization disorders (DPD) and body illusions.
The temporal-parietal junction (TPJ) is a key structure for the embodiment, term referred to as the sense of being localized within one's physical body and is a fundamental aspect of the self. On the contrary, the sense of disembodiment, an alteration of one's sense of self or the sense of being localized out of one's physical body, is a prominent feature in specific dissociative disorders, namely depersonalization/derealization disorders (DPD). The aims of the study were to provide: 1) a qualitative synthesis of the effect of Transcranial Magnetic Stimulation (TMS), taking into account its use for therapeutic and experimental purposes; 2) a better understanding on whether the use of TMS could support the treatment of DPD and other clinical conditions in which depersonalization and derealization are displayed. To identify suitable publications, an online search of the PubMed, Cochrane Library, Web of science and Scopus databases was performed using relevant search terms. In addition, an in-depth search was performed by screening review articles and the references section of each included articles. Our search yielded a total of 108 records through multiple databases searching and one additional record was identified through other sources. After duplicates removal, title and abstract reading, we retained 16 records for the assessment of eligibility. According to our inclusion criteria, we retained 8 studies. The selected studies showed that TMS targeting the TPJ is a promising technique for treating disembodiment phenomena DPD and for inducing reversible disembodiment states in healthy subjects. These data represent the first step towards a greater understanding of possible treatments to be used in disembodiment disorders. The use of TMS over the TPJ appears to be promising for treating disembodiment phenomena.
PubMed: 33709023
DOI: 10.3934/Neuroscience.2021009 -
PloS One 2021Dissociative experiences occur across a range of mental health disorders. However, the term 'dissociation' has long been argued to lack conceptual clarity and may...
BACKGROUND
Dissociative experiences occur across a range of mental health disorders. However, the term 'dissociation' has long been argued to lack conceptual clarity and may describe several distinct phenomena. We therefore aimed to conceptualise and empirically establish a discrete subset of dissociative experiences and develop a corresponding assessment measure.
METHODS
First, a systematic review of existing measures was carried out to identify themes across dissociative experiences. A theme of 'Felt Sense of Anomaly' (FSA) emerged. Second, assessment items were generated based on this construct and a measure developed using exploratory (EFA) and confirmatory (CFA) factor analyses of 8861 responses to an online self-report survey. Finally, the resulting measure was validated via CFA with data from 1031 patients with psychosis.
RESULTS
'Felt sense of anomaly' (FSA) was identified as common to many dissociative experiences, affecting several domains (e.g. body) and taking different forms ('types'; e.g. unfamiliarity). Items for a novel measure were therefore systematically generated using a conceptual framework whereby each item represented a type-by-domain interaction (e.g. 'my body feels unfamiliar'). Factor analysis of online responses found that FSA-dissociation manifested in seven ways: anomalous experiences of the self, body, and emotion, and altered senses of familiarity, connection, agency, and reality (Χ2 (553) = 4989.435, p<0.001, CFI = 0.929, TLI = 0.924, RMSEA = 0.052, SRMR = 0.047). Additionally, a single-factor 'global FSA' scale was produced (Χ2 (9) = 312.350, p<0.001, CFI = 0.970, TLI = 0.950, RMSEA = 0.107, SRMR = 0.021). Model fit was adequate in the clinical (psychosis) group (Χ2 (553) = 1623.641, p<0.001, CFI = 0.927, TLI = 0.921, RMSEA = 0.043, SRMR = 0.043). The scale had good convergent validity with a widely used dissociation scale (DES-II) (non-clinical: r = 0.802), excellent internal reliability (non-clinical: Cronbach's alpha = 0.98; clinical: Cronbach's alpha = 0.97), and excellent test-retest reliability (non-clinical: ICC = 0.92). Further, in non-clinical respondents scoring highly on a PTSD measure, CFA confirmed adequate model fit (Χ2 (553) = 4758.673, CFI = 0.913, TLI = 0.906, RMSEA = 0.052, SRMR = 0.054).
CONCLUSIONS
The Černis Felt Sense of Anomaly (ČEFSA) scale is a novel measure of a subset of dissociative experiences that share a core feature of FSA. It is psychometrically robust in both non-clinical and psychosis groups.
Topics: Dissociative Disorders; Factor Analysis, Statistical; Humans; Psychometrics; Self Report
PubMed: 33626089
DOI: 10.1371/journal.pone.0247037 -
The Cochrane Database of Systematic... Jul 2020Conversion and dissociative disorders are conditions where people experience unusual neurological symptoms or changes in awareness or identity. However, symptoms and... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Conversion and dissociative disorders are conditions where people experience unusual neurological symptoms or changes in awareness or identity. However, symptoms and clinical signs cannot be explained by a neurological disease or other medical condition. Instead, a psychological stressor or trauma is often present. The symptoms are real and can cause significant distress or problems with functioning in everyday life for the people experiencing them.
OBJECTIVES
To assess the beneficial and harmful effects of psychosocial interventions of conversion and dissociative disorders in adults.
SEARCH METHODS
We conducted database searches between 16 July and 16 August 2019. We searched Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and eight other databases, together with reference checking, citation searching and contact with study authors to identify additional studies. SELECTION CRITERIA: We included all randomised controlled trials that compared psychosocial interventions for conversion and dissociative disorders with standard care, wait list or other interventions (pharmaceutical, somatic or psychosocial). DATA COLLECTION AND ANALYSIS: We selected, quality assessed and extracted data from the identified studies. Two review authors independently performed all tasks. We used standard Cochrane methodology. For continuous data, we calculated mean differences (MD) and standardised mean differences (SMD) with 95% confidence interval (CI). For dichotomous outcomes, we calculated risk ratio (RR) with 95% CI. We assessed and downgraded the evidence according to the GRADE system for risk of bias, imprecision, indirectness, inconsistency and publication bias.
MAIN RESULTS
We included 17 studies (16 with parallel-group designs and one with a cross-over design), with 894 participants aged 18 to 80 years (female:male ratio 3:1). The data were separated into 12 comparisons based on the different interventions and comparators. Studies were pooled into the same comparison when identical interventions and comparisons were evaluated. The certainty of the evidence was downgraded as a consequence of potential risk of bias, as many of the studies had unclear or inadequate allocation concealment. Further downgrading was performed due to imprecision, few participants and inconsistency. There were 12 comparisons for the primary outcome of reduction in physical signs. Inpatient paradoxical intention therapy compared with outpatient diazepam: inpatient paradoxical intention therapy did not reduce conversive symptoms compared with outpatient diazepam at the end of treatment (RR 1.44, 95% CI 0.91 to 2.28; 1 study, 30 participants; P = 0.12; very low-quality evidence). Inpatient treatment programme plus hypnosis compared with inpatient treatment programme: inpatient treatment programme plus hypnosis did not reduce severity of impairment compared with inpatient treatment programme at the end of treatment (MD -0.49 (negative value better), 95% CI -1.28 to 0.30; 1 study, 45 participants; P = 0.23; very low-quality evidence). Outpatient hypnosis compared with wait list: outpatient hypnosis might reduce severity of impairment compared with wait list at the end of treatment (MD 2.10 (higher value better), 95% CI 1.34 to 2.86; 1 study, 49 participants; P < 0.00001; low-quality evidence). Behavioural therapy plus routine clinical care compared with routine clinical care: behavioural therapy plus routine clinical care might reduce the number of weekly seizures compared with routine clinical care alone at the end of treatment (MD -21.40 (negative value better), 95% CI -27.88 to -14.92; 1 study, 18 participants; P < 0.00001; very low-quality evidence). Cognitive behavioural therapy (CBT) compared with standard medical care: CBT did not reduce monthly seizure frequency compared to standard medical care at end of treatment (RR 1.56, 95% CI 0.39 to 6.19; 1 study, 16 participants; P = 0.53; very low-quality evidence). CBT did not reduce physical signs compared to standard medical care at the end of treatment (MD -4.75 (negative value better), 95% CI -18.73 to 9.23; 1 study, 61 participants; P = 0.51; low-quality evidence). CBT did not reduce seizure freedom compared to standard medical care at end of treatment (RR 2.33, 95% CI 0.30 to 17.88; 1 trial, 16 participants; P = 0.41; very low-quality evidence). Psychoeducational follow-up programmes compared with treatment as usual (TAU): no study measured reduction in physical signs at end of treatment. Specialised CBT-based physiotherapy inpatient programme compared with wait list: no study measured reduction in physical signs at end of treatment. Specialised CBT-based physiotherapy outpatient intervention compared with TAU: no study measured reduction in physical signs at end of treatment. Brief psychotherapeutic intervention (psychodynamic interpersonal treatment approach) compared with standard care: brief psychotherapeutic interventions did not reduce conversion symptoms compared to standard care at end of treatment (RR 0.12, 95% CI 0.01 to 2.00; 1 study, 19 participants; P = 0.14; very low-quality evidence). CBT plus adjunctive physical activity (APA) compared with CBT alone: CBT plus APA did not reduce overall physical impacts compared to CBT alone at end of treatment (MD 5.60 (negative value better), 95% CI -15.48 to 26.68; 1 study, 21 participants; P = 0.60; very low-quality evidence). Hypnosis compared to diazepam: hypnosis did not reduce symptoms compared to diazepam at end of treatment (RR 0.69, 95% CI 0.39 to 1.24; 1 study, 40 participants; P = 0.22; very low-quality evidence). Outpatient motivational interviewing (MI) and mindfulness-based psychotherapy compared with psychotherapy alone: psychotherapy preceded by MI might decrease seizure frequency compared with psychotherapy alone at end of treatment (MD 41.40 (negative value better), 95% CI 4.92 to 77.88; 1 study, 54 participants; P = 0.03; very low-quality evidence). The effect on the secondary outcomes was reported in 16/17 studies. None of the studies reported results on adverse effects. In the studies reporting on level of functioning and quality of life at end of treatment the effects ranged from small to no effect.
AUTHORS' CONCLUSIONS
The results of the meta-analysis and reporting of single studies suggest there is lack of evidence regarding the effects of any psychosocial intervention on conversion and dissociative disorders in adults. It is not possible to draw any conclusions about potential benefits or harms from the included studies.
Topics: Adult; Aged; Aged, 80 and over; Anti-Anxiety Agents; Conversion Disorder; Diazepam; Humans; Hypnosis; Middle Aged; Psychotherapy; Randomized Controlled Trials as Topic; Young Adult
PubMed: 32681745
DOI: 10.1002/14651858.CD005331.pub3 -
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 -
Medicina (Kaunas, Lithuania) Feb 2020The current psychopharmacological treatment approaches for major depression focus on monoaminergic interventions, which are ineffective in a large proportion of... (Meta-Analysis)
Meta-Analysis
Safety and Tolerability of Ketamine Use in Treatment-Resistant Bipolar Depression Patients with Regard to Central Nervous System Symptomatology: Literature Review and Analysis.
The current psychopharmacological treatment approaches for major depression focus on monoaminergic interventions, which are ineffective in a large proportion of patients. Globally, treatment-resistant bipolar depression (TRBD) affects up to 33% of depressive patients receiving treatment. Certain needs are still unmet and require new approaches. Many studies are in favor of treatments with ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, even in single use, whose effects emerge in minutes to hours post administration. However, little data are available on ketamine performance in TRBD patients with somatic comorbidities, including highly prevalent ones, i.e., cardiovascular disease (heart failure, hypertension, post-myocardial infarct, arrhythmias, etc.) diabetes, and obesity, and depression-associated comorbidities such as stroke, epilepsy, as well as in the elderly population. The literature shows that treatment with ketamine is efficacious and safe, and the majority of adverse drug reactions are mild and tend to mostly disappear within 30 min to 2 h of ketamine administration.
Topics: Administration, Intravenous; Administration, Oral; Antidepressive Agents; Bipolar Disorder; Comorbidity; Depressive Disorder, Major; Depressive Disorder, Treatment-Resistant; Dissociative Disorders; Humans; Ketamine
PubMed: 32050466
DOI: 10.3390/medicina56020067