scholarly journals A neurostructural biomarker of dissociative amnesia: a hippocampal study in dissociative identity disorder

2021 ◽  
pp. 1-9
Author(s):  
Lora I. Dimitrova ◽  
Sophie L. Dean ◽  
Yolanda R. Schlumpf ◽  
Eline M. Vissia ◽  
Ellert R. S. Nijenhuis ◽  
...  
Keyword(s):  
Molecular Layer ◽  
Dissociative Identity Disorder ◽  
Hippocampal Volume ◽  
Vital Role ◽  
Emotional Neglect ◽  
Dissociative Amnesia ◽  
Scale Scores ◽  
Cornu Ammonis ◽  
Partial Correlations ◽  
Dissociative Symptom

Abstract Background Little is known about the neural correlates of dissociative amnesia, a transdiagnostic symptom mostly present in the dissociative disorders and core characteristic of dissociative identity disorder (DID). Given the vital role of the hippocampus in memory, a prime candidate for investigation is whether total and/or subfield hippocampal volume can serve as biological markers of dissociative amnesia. Methods A total of 75 women, 32 with DID and 43 matched healthy controls (HC), underwent structural magnetic resonance imaging (MRI). Using Freesurfer (version 6.0), volumes were extracted for bilateral global hippocampus, cornu ammonis (CA) 1–4, the granule cell molecular layer of the dentate gyrus (GC-ML-DG), fimbria, hippocampal−amygdaloid transition area (HATA), parasubiculum, presubiculum and subiculum. Analyses of covariance showed volumetric differences between DID and HC. Partial correlations exhibited relationships between the three factors of the dissociative experience scale scores (dissociative amnesia, absorption, depersonalisation/derealisation) and traumatisation measures with hippocampal global and subfield volumes. Results Hippocampal volumes were found to be smaller in DID as compared with HC in bilateral global hippocampus and bilateral CA1, right CA4, right GC-ML-DG, and left presubiculum. Dissociative amnesia was the only dissociative symptom that correlated uniquely and significantly with reduced bilateral hippocampal CA1 subfield volumes. Regarding traumatisation, only emotional neglect correlated negatively with bilateral global hippocampus, bilateral CA1, CA4 and GC-ML-DG, and right CA3. Conclusion We propose decreased CA1 volume as a biomarker for dissociative amnesia. We also propose that traumatisation, specifically emotional neglect, is interlinked with dissociative amnesia in having a detrimental effect on hippocampal volume.

scholarly journals Alteration within the Hippocampal Volume in Patients with LHON Disease—7 Tesla MRI Study

2020 ◽  
Vol 10 (1) ◽  
pp. 14
Author(s):  
Cezary Grochowski ◽  
Kamil Jonak ◽  
Marcin Maciejewski ◽  
Andrzej Stępniewski ◽  
Mansur Rahnama-Hezavah
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Molecular Layer ◽  
Three Dimensional ◽  
Hippocampal Volume ◽  
7 Tesla ◽  
Diagnostic Process ◽  
Resonance Imaging ◽  
The Right

Purpose: The aim of this study was to assess the volumetry of the hippocampus in the Leber’s hereditary optic neuropathy (LHON) of blind patients. Methods: A total of 25 patients with LHON were randomly included into the study from the national health database. A total of 15 patients were selected according to the inclusion criteria. The submillimeter segmentation of the hippocampus was based on three-dimensional spoiled gradient recalled acquisition in steady state (3D-SPGR) BRAVO 7T magnetic resonance imaging (MRI) protocol. Results: Statistical analysis revealed that compared to healthy controls (HC), LHON subjects had multiple significant differences only in the right hippocampus, including a significantly higher volume of hippocampal tail (p = 0.009), subiculum body (p = 0.018), CA1 body (p = 0.002), hippocampal fissure (p = 0.046), molecular layer hippocampus (HP) body (p = 0.014), CA3 body (p = 0.006), Granule Cell (GC) and Molecular Layer (ML) of the Dentate Gyrus (DG)–GC ML DG body (p = 0.003), CA4 body (p = 0.001), whole hippocampal body (p = 0.018), and the whole hippocampus volume (p = 0.023). Discussion: The ultra-high-field magnetic resonance imaging allowed hippocampus quality visualization and analysis, serving as a powerful in vivo diagnostic tool in the diagnostic process and LHON disease course assessment. The study confirmed previous reports regarding volumetry of hippocampus in blind individuals.

Dissociative Amnesia and Dissociative Identity Disorder

2021 ◽  
Vol 11 (73) (1) ◽  
pp. 207-216
Author(s):  
Bogdan Eduard Patrichi ◽  
Cristina Ene ◽  
Cristina Rîndaşu ◽  
Arina Cipriana Trifu
Keyword(s):  
Life Events ◽  
Dissociative Identity Disorder ◽  
Current Paper ◽  
Dissociative Disorders ◽  
Contemporary Society ◽  
Traumatic Life Events ◽  
Dissociative Amnesia ◽  
The Individual ◽  
The Mind

The current paper aims to describe and exemplify the pathology that is increasingly common in contemporary society, compared to the Freudian period in which repression was dominating. Dissociative disorders are usually associated with overwhelming stress, which can be generated by traumatic life events, accidents or disasters experienced directly or witnessed by the individual, or unbearable inner conflicts, which force the mind to separate incompatible or unacceptable pieces of information and feelings.

Sleep duration, sleep problems and perceived stress are associated with hippocampal subfield volumes in later life: Findings from The Irish Longitudinal Study on Ageing (TILDA)

SLEEP ◽  
2021 ◽  
Author(s):  
Céline De Looze ◽  
Joanne C Feeney ◽  
Siobhan Scarlett ◽  
Rebecca Hirst ◽  
Silvin P Knight ◽  
...  
Keyword(s):  
Longitudinal Study ◽  
Sleep Duration ◽  
Perceived Stress ◽  
Sleep Problems ◽  
Molecular Layer ◽  
Hippocampal Volume ◽  
Ordinary Least Squares ◽  
Cross Sectional ◽  
Stress Changes

Abstract Study Objectives This study examines the cross-sectional and two-year follow-up relationships between sleep and stress and total hippocampal volume and hippocampal subfield volumes among older adults. Methods 417 adults (aged 68.8±7.3; 54% women) from the Irish Longitudinal Study on Ageing completed an interview, a questionnaire and multiparametric brain MRI. The relationships between self-reported sleep duration, sleep problems, perceived stress and total hippocampal volume were examined by using ordinary least squares regressions. Linear mixed-effects models were used to investigate the relationships between sleep duration, sleep problems, perceived stress, changes in these measures over two-years and hippocampal subfield volumes. Results No cross-sectional and follow-up associations between sleep and total hippocampal volume and between stress and total hippocampal volume were found. By contrast, Long sleep (≥9-10 hours / night) was associated with smaller volumes of molecular layer, hippocampal tail, presubiculum and subiculum. The co-occurrence of Short sleep (≤6 hours) and perceived stress was associated with smaller cornu ammonis 1, molecular layer, subiculum and tail. Sleep problems independently and in conjunction with higher stress, and increase in sleep problems over 2 years were associated with smaller volumes of these same subfields. Conclusion Our study highlights the importance of concurrently assessing sub-optimal sleep and stress for phenotyping individuals at risk of hippocampal subfield atrophy.

Dissociative Disorders

2017 ◽  
Author(s):  
David Matuskey
Keyword(s):  
Dissociative Identity Disorder ◽  
Dissociative Disorders ◽  
Dissociative Amnesia ◽  
Depersonalization Disorder

In this chapter topics related to dissociative disorders are reviewed including dissociative amnesia, dissociative fugue, dissociative identity disorder, depersonalization disorder and derealization disorder

Hippocampal volume is more related to patient-reported memory than objective memory performance in early multiple sclerosis

2020 ◽  
pp. 135245852092283
Author(s):  
Lisa Glukhovsky ◽  
Rachel Brandstadter ◽  
Victoria M Leavitt ◽  
Stephen Krieger ◽  
Korhan Buyukturkoglu ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Memory Performance ◽  
Hippocampal Volume ◽  
Magnetic Resonance Images ◽  
Longitudinal Assessment ◽  
Subjective Memory ◽  
Cross Sectional ◽  
Memory Decline ◽  
Patient Reported ◽  
Partial Correlations

Background: When persons with multiple sclerosis (MS) report memory decline but objective memory performance is normal, there is a bias toward believing objective test results. Objective: Investigate whether subjective memory decline or objective memory performance is more related to hippocampal and hippocampal subfield volumes in early MS. Methods: Persons with early MS ( n = 185; ⩽5.0 years diagnosed) completed a subjective memory questionnaire; an objective memory composite was derived from four memory tests. Total hippocampal and subfield volumes were derived from high-resolution 3.0 T magnetic resonance images (MRIs). Partial correlations assessed links between hippocampal volumes and both subjective and objective memory, controlling for age, sex, mood, and pre-morbid intelligence quotient (IQ). Results: Lower total hippocampal and CA1 volumes were related to worse subjective memory but not objective memory (controlling for multiple comparisons). Correlations between subjective memory and both CA1 and subiculum were significantly stronger than were correlations between objective memory and these subfields. Patients in the worst tertile of subjective memory complaints (but not objective memory) had lower hippocampal volumes than 35 demographically similar healthy controls. Conclusion: Patient-report is inherently a longitudinal assessment of within-person memory change in everyday life, which may be more sensitive to subtle disease-related changes than cross-sectional objective tests. Findings align with the aging literature.

scholarly journals DID in resurgence, not retreat

2019 ◽  
Vol 25 (05) ◽  
pp. 296-298
Author(s):  
Pamela Radcliffe ◽  
Keith Rix
Keyword(s):  
Professional Training ◽  
Dissociative Identity Disorder ◽  
Human Memory ◽  
Diagnosis And Treatment ◽  
Guidance Document ◽  
Treatment Model ◽  
Potential Harm ◽  
Treatment Techniques ◽  
Dissociative Amnesia ◽  
Randomised Controlled

SUMMARYContrary to the assertion of Paris, diverse indicators suggest that the diagnosis and treatment of dissociative identity disorder (DID) are resurgent rather than retreating. This commentary reviews the evidence that justifies the description of this condition as controversial, including research into dissociative amnesia. The potential harm that can result from a diagnosis of DID and risky treatment techniques, including hypnosis and abreaction, are described. It is suggested that this scientifically unproven and potentially harmful treatment model should be confronted and quelled and its diagnosis and treatment subjected to critical clinical review, including randomised controlled trials, as a matter of urgency. A plea is made for the Royal College of Psychiatrists to update its 1997 guidance document and for professional training to incorporate updated psychological and neurobiological research on human memory.DECLARATION OF INTERESTNone.

scholarly journals The distribution of serotonergic nerve on the hippocampus of the fruit bats (Rousettus amplexicaudatus)

2019 ◽  
Vol 12 (9) ◽  
pp. 1460-1466 ◽  
Author(s):  
Vivin Wirawati ◽  
Nourrisma D. A. Widiati ◽  
Geraldus Gunawan ◽  
Golda R. Saragih ◽  
Puspa Hening ◽  
...  
Keyword(s):  
Learning And Memory ◽  
Molecular Layer ◽  
Stratum Radiatum ◽  
Fruit Bats ◽  
Cornu Ammonis ◽  
Stratum Lucidum ◽  
Paraffin Block ◽  
Hippocampus Proper ◽  
La Jolla ◽  
The Brain

Background: Rousettus amplexicaudatus is one of the old world fruit bats, commonly known in Javanese word as codot belongs to Order Chiroptera and suborder Megachiroptera. R. amplexicaudatus possessed an outstanding visual ability, which helps in the process of searching for food. Those activities process and save within the brain involving the learning and memory activities. Learning and memory activities are centered around the hippocampus with the help of serotonergic nerve. Aim: This study conducted to identify the morphology and distribution of serotonergic nerve (5-hydroxytryptamine) in the hippocampus of R. amplexicaudatus, which related to the function of serotonin within the learning and memory process. Materials and Methods: Five R. amplexicaudatus bats were brought from Gunung Kidul cave, Yogyakarta, Java Island, Indonesia. The bats were anesthetized using ketamine and xylazine. R. amplexicaudatus then perfused intracardially. The brain samples were collected processed into paraffin block, and a further cut in 8 μm thickness serially. The tissue slides were stained using hematoxylin-eosin, cresyl echt violet, and immunohistochemistry with rabbit's anti-serotonin (1:200). The results observed and analyzed quantitatively and qualitatively using image J (https://imagej.nih.gov/ij/) (Bethesda, Maryland, USA) and GraphPad Prism 7 (La Jolla, CA, USA). Results: The hippocampus of R. amplexicaudatus composed of the dentate gyrus (DG), hippocampus proper (cornu ammonis 3 [CA3], and CA1 as the main area for learning memory), and subiculum. On the DG serotonin immunoreactive cells found within the granular layer (132±35.03 cells/mm2), polymorphic stratum (86.33±11.23 cells/mm2), and molecular layer (93±1 cells/mm2). Meanwhile, on CA3 area, the immunoreactive cells for serotonin found in each stratum. The number of immunoreactive cells on each stratum from highest to the lowest are stratum pyramidal 123.33±15.88 cell/mm2, stratum molecular 63±13.11 cell/mm2, stratum lucidum 62.67±8.08 cell/mm2, stratum radiatum 55.33±510.21 cell/mm2, stratum oriens 48±3.46 cell/mm2, and stratum alveus 28.67±2.52 cell/mm2. In addition, in CA1 also hampers the immunoreactive cells in the pyramidal stratum, molecular, lucidum, oriens, radiatum, and alveus layer, respectively, of each 91±27.40 cell/mm2, 60.33±20.65 cell/mm2, 53.67±4.51 cell/mm2 44.33±10.40 cell/mm2, 41.33±5.51 cell/mm2, and 27±4 cell/mm2. Conclusion: Taking together the distribution of serotonin-immunoreactive cells in the hippocampus of R. amplexicaudatus mostly found on CA3 followed by CA 1 and DG.

The Presence of the Temporal Horn Exacerbates the Vulnerability of Hippocampus during Head Impacts

2021 ◽  
Author(s):  
Zhou Zhou ◽  
Xiaogai Li ◽  
August Domel ◽  
Emily Dennis ◽  
Marios Georgiadis ◽  
...  
Keyword(s):  
Collegiate Athletes ◽  
Human Head ◽  
Hippocampal Volume ◽  
Arbitrary Lagrangian Eulerian ◽  
Predisposing Factor ◽  
Head Impacts ◽  
Strain And Strain Rate ◽  
Temporal Horn ◽  
Cornu Ammonis ◽  
Coupling Approach

Hippocampal injury is common in traumatic brain injury (TBI) patients, but the underlying pathogenesis remains elusive. In this study, we hypothesize that the presence of the adjacent fluid-containing temporal horn exacerbates the biomechanical vulnerability of the hippocampus. Two finite element models of the human head were used to investigate this hypothesis, one with and one without the temporal horn, and both including a detailed hippocampal subfield delineation. A fluid-structure interaction coupling approach was used to simulate the brain-ventricle interface, in which the intraventricular cerebrospinal fluid was represented by an arbitrary Lagrangian-Eulerian multi-material formation to account for its fluid behavior. By comparing the response of these two models under identical loadings, the model that included the temporal horn predicted increased magnitudes of strain and strain rate in the hippocampus with respect to its counterpart without the temporal horn. This specifically affected cornu ammonis (CA) 1 (CA1), CA2/3, hippocampal tail, subiculum, and the adjacent amygdala and ventral diencephalon. These computational results suggest the presence of the temporal horn is a predisposing factor for the prevalence of hippocampal injury, advancing the understanding of hippocampal injury during head impacts. A corresponding analysis in an imaging cohort of collegiate athletes found that temporal horn size negatively correlates with hippocampal volume in the same subfields, suggesting a possible real-world correlation whereby a larger temporal horn may be associated with decreased hippocampal volume. Our biomechanical and neuroimaging effort collectively highlight the mechanobiological and anatomical interdependency between the hippocampus and temporal horn.

scholarly journals Primate hippocampus size and organization are predicted by sociality but not diet

2019 ◽  
Vol 286 (1914) ◽  
pp. 20191712 ◽  
Author(s):  
Orlin S. Todorov ◽  
Vera Weisbecker ◽  
Emmanuel Gilissen ◽  
Karl Zilles ◽  
Alexandra A. de Sousa
Keyword(s):  
Sex Differences ◽  
Home Range ◽  
Group Size ◽  
Phylogenetic Signal ◽  
Spatial Navigation ◽  
Ecological Factors ◽  
Hippocampal Volume ◽  
The Other ◽  
Sex Dimorphism ◽  
Cornu Ammonis

The hippocampus is well known for its roles in spatial navigation and memory, but it is organized into regions that have different connections and functional specializations. Notably, the region CA2 has a role in social and not spatial cognition, as is the case for the regions CA1 and CA3 that surround it. Here, we investigated the evolution of the hippocampus in terms of its size and organization in relation to the evolution of social and ecological variables in primates, namely home range, diet and different measures of group size. We found that the volumes within the whole cornu ammonis coevolve with group size, while only the volume of CA1 and subiculum can also be predicted by home range. On the other hand, diet, expressed as a shift from folivory towards frugivory, was shown to not be related to hippocampal volume. Interestingly, CA2 was shown to exhibit phylogenetic signal only against certain measures of group size, but not with ecological factors. We also found that sex differences in the hippocampus are related to body size sex dimorphism. This is in line with reports of sex differences in hippocampal volume in non-primates that are related to social structure and sex differences in behaviour. Our findings support the notion that in primates, the hippocampus is a mosaic structure evolving in line with social pressures, where certain subsections evolve in line with spatial ability too.

scholarly journals Primate hippocampus size and organization are predicted by sociality but not diet

2019 ◽  
Author(s):  
Orlin S. Todorov ◽  
Vera Weisbecker ◽  
Emmanuel Gilissen ◽  
Karl Zilles ◽  
Alexandra A. de Sousa
Keyword(s):  
Sex Differences ◽  
Home Range ◽  
Group Size ◽  
Phylogenetic Signal ◽  
Spatial Navigation ◽  
Ecological Factors ◽  
Hippocampal Volume ◽  
The Other ◽  
Sex Dimorphism ◽  
Cornu Ammonis

AbstractThe hippocampus is well known for its roles in spatial navigation and memory, but it is organized into regions that have different connections and functional specializations. Notably, the region CA2 has a role in social and not spatial cognition, as is the case for the regions CA1 and CA3 that surround it. Here we investigated the evolution of the hippocampus in terms of its size and organization in relation to the evolution of social and ecological variables in primates, namely home range, diet and different measures of group size. We found that the volumes within the whole cornu ammonis coevolve with group size, while only the volume of CA1 and subiculum can also be predicted by home range. On the other hand, diet, expressed as a shift from folivory toward frugivory, was shown to not be related to hippocampal volume. Interestingly, CA2 was shown to exhibit phylogenetic signal only against certain measures of group size but not with ecological factors. We also found that sex differences in the hippocampus are related to body size sex dimorphism. This is in line with reports of sex differences in hippocampal volume in non-primates that are related to social structure and sex differences in behaviour. Our findings support the notion that in primates, the hippocampus is a mosaic structure evolving in line with social pressures, where certain subsections evolve in line with spatial ability too.

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