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PubMedDate not supplied

[Study of dissociative disorders and depersonalization in a sample of young adult French population].

UNLABELLED: Questioned by several researches about dissociative disorders, the authors study differences established on the nosographic register, through a quantitative study and a psychodynamic argumentation in a sample of french population. From the utilisation of the Dissociative Experiences Scale (DES) created by Bernstein E and Putnam FW (1986), which is an excellent screening tool for dissociative disorders and constructed on DSM II diagnostic criterions, the authors will show the interest of a psychodynamic analysis of dissociative disorders, in the face of the diagnostic difficulty in relation to several approaches of this concept. This difficulty is studied giving the background to dissociative disorders and depersonalization. Ionescu (1999) shows that between 1890 and 1910 dissociation represents one of major themes of psychology, psychopathology and psychiatry. Then, this interest about dissociation decreases and will be almost non-existent in the middle of the twentieth century. The interest for dissociative disorder will grow in the eighties with north-american studies about multiple personality disorders. Until 1980, dissociative disorders exist in DSM II as a list of symptoms included into hysterical neurosis, among the conversive disorders. In 1980, the publication of DSM III replaces the notion of hysteria with the notion of dissociative disorder. In this way, we can see on the one hand somatoform disorders quarterly corresponding to the ancient version of conversive hysteria, and on the other hand dissociative disorders characterized by a perturbation of consciousness, memory, identity or perception of environment. In 1994, The DSM IV delete the notion of hysteria and neurosis and keeps only the notion of dissociative disorders. They include now the five following categories: dissociative amnesia, dissociative fugue, depersonalization disorder, dissociative identity disorder, dissociative disorder not otherwise specified (including derealization). Depersonalization disorders consist of "persistent or recurrent episodes of depersonalization characterized by a feeling of detachment or estrangement from one's self. The individual may feel like an automation or like he or she is living in a dream or movie" (DSM IV). Depersonalization disorder cannot be diagnosed if it is part of schizophrenia, panic disorder, acute stress disorder or dissociative identity disorder. Various depressive disorders, hypocondriasis or obsessive-compulsive disorders can accompany depersonalization disorder. The first purpose of this study will search the frequency of dissociative disorders and depersonalization in a sample of normal population. Further, the inclusion of depersonalization amongst dissociative disorders seems not so evident: depersonalization belongs to self-consciousness disorder in french psychiatry. This fact seems more logical insofar as dissociative disorders have all together a memory and consciousness perturbation, and this perturbation is missing from depersonalization's feeling. The second purpose will be to clarify and specify the particularity of depersonalization among dissociative diorders, from the psychopathological point of view. METHODOLOGY: The sample (n = 248) is made up of french young adults aged 17 to 30 (mean age = 20, SD = 15 and 24% is male population). Subjects were streamming from universities. The screening tool which was used is the Dissociative Experiences Scale, a 28-item patient questionnaire regarding various dissociative symptoms. The subject is asked to indicate the percentage of time, to the nearest 5%, that particular symptom is experienced. The score is made by adding the various percentages and finding a mean that is expressed in numbers from 0 to 100. Normal scores are in the range of 5 to 15 in american adults. RESULTS: The utilization of principal component analysis (PCA) with varimax rotation is justified by the will to compare this study with American's studies. The mean score obtained is 17.44%, and 13.3% of the scores exceed a psychiatric threshold at 30%. The descriptive analysis shows that the component 1 (PCA without varimax rotation) represents 33.02% of total explained variance. This result demonstrates that the structure of the DES is based on one concept, the same as the american population, it is the concept of dissociation. The Principal Component Analysis with varimax rotation of the DES ratings yielded a tree-factor solution: imaginative absorption (F1), depersonalization-derealization (F2) and dissociative amnesia (F3). Mean score for each factor is respectively: F1 = 21.56%, F2 = 13.95%, F3 = 11.04%. DES reliability was studied through computation of Cronbach's coefficient (0.92). The PCA with varimax rotation brings to the fore a full dissociative disorder without any trouble of memory and consciousness. This fact questions again once more the link between hysteria and dissociative disorders. There is here a clinical distinction between depersonalization-derealization and other dissociative disorders. Indeed, the absence of significant alteration of memory and conscience is specific of depersonalization and derealization in this study. CONCLUSION: Finally, this study concurs with DSM IV dissociative criterions. At last, one factor of PCA is composed by the association of depersonalization and derealization, in contradiction with DSM IV definition. This result shows that, into the french population, we cannot divide the two concepts.

Adult↗
PubMed1975

Dissociation of human follicle-stimulating hormone. Comparison with luteinizing hormone.

Rat testis tissue receptor assays were utilized to study the kinetics of dissociation of human follicle-stimulating hormone (hFSH) and luteinizing hormone (hLH) under varying conditions of urea concentration and pH. In these competitive protein binding assays, 125I-hFSH and 125I-hLH were the radioligands and hormone dissociation was followed by a decrease in the ability of the dissociating hormone to inhibit uptake of the radioligand by tissue receptors. Rate data for dissociation of the gonadotropins were analyzed for quality of fit to first or second order integrated rate equations by nonlinear regression analysis. Treatment of hFSH with 4 M urea at pH 8 and 25 degrees for 22 hours did not result in significant dissociation, whereas in 8 M urea, over 90% dissociation was observed. The rate of dissociation of hFSH in 8 M urea was increased approximately 4-fold by raising the temperature from 25 to 37 degrees. Similar results were obtained when dissociation of hFSH was followed through use of an accepted whole animal bioassay for FSH, thus confirming the reliability of the tissue receptor assay for such dissociation studies. Kinetic studies showed that hFSH was undissociated by incubation in 6 M urea of pH 8 after 4 hours at 25 degrees. In contrast, hLH was 90% dissociated under similar conditions. This differential rate of inactivation of hLH allowed preparation of hFSH having significant reduced levels of contaminating LH activity, as determined by tissue receptor assays and by whole animal bioassays. Marked differences were noted in the rate of dissociation of hFSH and hLH under acid conditions. hFSH completely dissociated after approximately 2 min of incubation of pH 2 (25 degrees), and over 90% dissociated after 15 min of incubation at pH 3. In contrast, hLH was dissociated 60% after 20 min of incubation at pH 2 (25 degrees) and 40% dissociated after 60 min at pH 3. Neither hormone was significantly dissociated at pH 4.4 after 60 min, but hFSH showed a slightly greater rate of dissociation than did LH in the period between 1 and 23 hours of incubation at that pH. hFSH and hLH were relatively resistant to dissociation after incubation at pH 12 for 1 hour, bu;t dissociated significantly after incubation for 22 hours at that pH. The time course for dissociation of hFSH or hLH under the various conditions described above did not conform clearly to either first or second order kinetics, indicating that the over-all dissociation process represents a mixed order reaction. It appears that urea or acid-induced denaturation of one or both subunits of hLH and hFSH may occur prior to their dissociation. The very rapid rate of dissociation at acid pH values, particularly of hFSH, indicate that ionic interactions contribute importantly to the subunit association phenomenon.

Animals↗
PubMedDate not supplied

Dissociative experiences in obsessive-compulsive disorder and trichotillomania: clinical and genetic findings.

A link between dissociation proneness in adulthood and self-reports of childhood traumatic events (including familial loss in childhood, sexual/physical abuse and neglect) has been documented. Several studies have also provided evidence for an association between dissociative experiences and trauma in patients with various psychiatric disorders, including post-traumatic stress disorder, borderline personality, dissociative identity and eating disorders. Based on the relative paucity of data on dissociation and trauma in obsessive-compulsive disorder (OCD) and trichotillomania (TTM), the primary objective of this study was to examine the relationship between trauma and dissociative experiences (DE) in these two diagnostic groups. Furthermore, the availability of clinical and genetic data on this sample allowed us to explore clinical and genetic factors relevant to this association. A total of 110 OCD and 32 TTM patients were compared with respect to the degree of dissociation (using the Dissociative Experiences Scale [DES]) and childhood trauma (using the Childhood Trauma Questionnaire [CTQ]). Patients were classified on the DES as either "high" (mean DES score >/= 30) or "low" (mean DES score < 30) dissociators. Additional clinical and genetic factors were also explored with chi-square and t tests as appropriate. A total of 15.8% of OCD patients and 18.8% of TTM patients were high dissociators. OCD and TTM groups were comparable on DES and CTQ total scores, and in both OCD and TTM groups, significant positive correlations were found between mean DES scores and mean CTQ subscores of emotional abuse, physical abuse, sexual abuse, and physical neglect. In the OCD group, high dissociators were significantly younger than low dissociators, and significantly more high dissociators than low dissociators reported a lifetime (current and past) history of tics (P <.001), Tourette's syndrome (P =.019), bulimia nervosa (P =.003), and borderline personality disorder (P =.027). In the TTM group, significantly more high dissociators than low dissociators reported (lifetime) kleptomania (P =.005) and depersonalisation disorder (P =.005). In the Caucasian OCD patients (n = 114), investigation of genetic polymorphisms involved in monoamine function revealed no significant differences between high and low dissociator groups. This study demonstrates a link between childhood trauma and DE in patients with OCD and TTM. High dissociative symptomatology may be present in a substantial proportion of patients diagnosed with these disorders. High dissociators may also be differentiated from low dissociators on some demographic features (e.g., lower age) and comorbidity profile (e.g., increased incidence of impulse dyscontrol disorders). Additional work is necessary before conclusions about the role of monoaminergic systems in mediating such dissociation can be drawn.

Adult↗
PubMedDate not supplied

Trauma-related dissociation: conceptual clarity lost and found.

OBJECTIVE: Imprecise conceptualizations of dissociation hinder understanding of trauma-related dissociation. An heuristic resolution for research and clinical practice is proposed. METHOD: Current conceptualizations of dissociation are critically examined. They are compared with a new theory that incorporates classical views on dissociation with other contemporary theories related to traumatization, viewing dissociation as a lack of integration among psychobiological systems that constitute personality, that is, as a structural dissociation of the personality. RESULTS: Most current views of dissociation are overinclusive and underinclusive. They embrace non-dissociative phenomena--rigid alterations in the level and field of consciousness--prevalent in non-traumatized populations, and which do not require structural dissociation. These views also largely disregard somatoform and positive symptoms of dissociation and underestimate integrative deficiencies, while emphasizing the psychological defensive function of dissociation. They do not offer a common psychobiological pathway for the spectrum of trauma-related disorders. Structural dissociation of the personality likely involves divisions among at least two psychobiological systems, each including a more or less distinct apperceptive centre, that is, a dissociative part of the personality. Three prototypical levels of structural dissociation are postulated to correlate with particular trauma-related disorders. CONCLUSIONS: Limitation of the concept of dissociation to structural dividedness of the personality sets it apart from related but non-dissociative phenomena and provides a taxonomy of dissociative symptoms. It postulates a common psychobiological pathway for all trauma-related disorders. Trauma-related dissociation is maintained by integrative deficits and phobic avoidance. This conceptualization advances diagnosis, classification, treatment and research of trauma-related disorders.

Brain Injuries↗
PubMed1996

Hypnotizability and traumatic experience: a diathesis-stress model of dissociative symptomatology.

OBJECTIVE: The authors propose a diathesis-stress model to describe how pathological dissociation may arise from an interaction between innate hypnotizability and traumatic experience. METHOD: To support the proposition that pathological dissociation may reflect autohypnotic process, the authors highlight clinical and research data indicating parallels between controlled hypnotic dissociative states and uncontrolled pathological dissociative symptoms and summarize evidence of hypnotizability in persons with psychiatric disorders that manifest these symptoms. The authors present this evidence by examining dissociative symptomatology in four psychological domains: perception, behavior and will, affect, and memory and identity. In addition, modern cognitive and neuropsychological models of dissociation are briefly reviewed. RESULTS: Several lines of evidence converge in support of the role of autohypnosis in pathological dissociation. There is considerable evidence that controlled formal hypnosis can produce a variety of dissociations of awareness and control that resemble many of the symptoms in uncontrolled pathological dissociative conditions; and it is possible to discern in dissociative pathology the features of absorption, dissociation, and suggestibility/automaticity that characterize formal hypnotic states. There is also accumulating evidence of high levels of hypnotic capacity in all groups with dissociative symptomatology that have been systematically assessed. In addition, the widespread and successful therapeutic use of hypnosis in the treatment of many dissociative symptoms and conditions (and the potential for hypnosis to induce dissociative symptomatology) also supports the assumption that hypnosis and pathological dissociation share an underlying process. CONCLUSIONS: High hypnotizability may be a diathesis for pathological dissociative states, particularly under conditions of acute traumatic stress.

Adult↗
PubMed1992

Dissociation of a native dimer to a molten globule monomer. Effects of pressure and dilution on the association equilibrium of arc repressor.

The monomer-dimer association reaction of Arc repressor was studied by pressure-induced dissociation and by dilution. The dissociation was measured by the decrease (red shift) in the average energy of emission of the tryptophan fluorescence. Pressure dissociation also promoted a decrease in the excited-state lifetime of the single tryptophanyl residue, Trp14. These observations suggest that Trp14 becomes exposed to an aqueous environment following dissociation. The pressure-dissociation curves were concentration dependent, with p1/2 (half-dissociation pressure) shifting to higher pressures as the concentration increased. The dissociation constant (KdO) obtained by extrapolating the pressure-dissociation curves to atmospheric pressure was similar to that determined from the dilution curve (KdO = 30 nM). An anomalous steepness of dissociation in response to dilution was observed, suggesting that conformational changes occur as a result of dissociation of Arc repressor. Binding of bis(8-anilinonaphthalene-1-sulfonate) to Arc repressor was not significantly affected by pressure dissociation, whereas thermal or urea denaturation was accompanied by a dramatic decrease in binding. These results suggest that the conformational changes that follow dissociation induced by pressure are more limited than those following denaturation. The tryptophan anisotropy decreased by about one-half, suggesting the dissociation of a globular dimer to a compact monomer. On the other hand, denaturation by urea promoted an increase in anisotropy, as expected for a random-coil conformation. Dissociated Arc has the hydrodynamic properties of a folded monomer. On the other hand, dissociated Arc has a high degree of exposure of hydrophobic side-chains, and the distribution of conformations is much broader than that in the folded dimer. These features suggest that the dissociated subunit is a molten globule. The subunit interaction was substantially increased by a single amino acid substitution (Pro8----Leu), and the free energy of stabilization amounted to -2.9 kcal/mol. This increased stability suggests that residue 8 is located in the dimer interface and that part of the tertiary and most of the quaternary structure constraints result from the interaction between the intersubunit beta-strands.

Anisotropy↗
PubMed1984

Kinetics and mechanism of dissociation of cooperatively bound T4 gene 32 protein-single-stranded nucleic acid complexes. 2. Changes in mechanism as a function of sodium chloride concentration and other solution variables.

The dissociation kinetics of bacteriophage T4 coded gene 32 protein-single-stranded nucleic acid complexes have been examined as a function of monovalent salt concentration, temperature, and pH in order to investigate the details of the dissociation of cooperatively bound protein. Fluorescence stopped-flow techniques were used, and irreversible dissociation was induced by a combination of [NaCl] jumps and mixing with excess nucleic acid competitor. This made it possible to directly investigate the irreversible dissociation process over a wide range of NaCl concentrations [e.g., from 50 mM to 0.60 M for the gene 32 protein-poly(A) complex], in the absence of reassociation. Over the entire salt range, the only dissociable species observed is the singly contiguously bound gene 32 protein which dissociates from the ends of protein clusters. However, the [NaCl] dependence of the dissociation rate constant suggests that two competing pathways exist for dissociation of cooperatively bound gene 32 protein from the ends of protein clusters. At high monovalent salt concentrations, dissociation is dominated by a single-step process, with log ke/log [NaCl] = 6.5 +/- 0.5; i.e., the dissociation rate constant increases with increasing NaCl concentration due to the uptake of approximately six monovalent ions upon dissociation. This indicates that singly contiguous protein dissociates directly into solution. However, at much lower [NaCl] the data suggest that gene 32 protein, when bound at the end of a protein cluster, dissociates by first sliding off the end to form a noncooperatively bound intermediate which subsequently dissociates. A quantitative model which incorporates the sliding pathway [Berg, O. G., Winter, R. B., & von Hippel, P. H. (1981) Biochemistry 20, 6929-6948] in the dissociation mechanism fits the data reasonably well and suggests that noncooperatively bound monomers of gene 32 protein may be capable of one-dimensional translocation along single-stranded nucleic acids as suggested by independent kinetic data on the association reaction [Lohman, T. M., & Kowalczykowski, S. C. (1981) J. Mol. Biol. 152, 67-109]. It is also observed that both the absolute dissociation rate constant for T4 gene 32 protein and its salt dependence are sensitive to the average molecular weight and polydispersity of the nucleic acid sample used. This is a general phenomenon exhibited by proteins that bind to nucleic acids in a highly cooperative manner.

Escherichia coli↗
PubMed2000

[Dissociative disorders: from Janet to DSM-IV].

I reviewed the literature on dissociation and dissociative disorders from Pierre Janet to DSM-IV, and examined the current trends in research. Janet's theory on hysteria is multifaceted, and is based on three psychological models. Based on a hierarchical model, Janet related hysteric symptoms to the activities within the lower strata of mental hierarchy (automatisms psychologiques), which were demonstrably shown in somnambulism. A second model was based on the concept of a psychological system, which was hypothetically composed of ideas, images, feelings, sensations, and movements. According to this model, dissociation of psychological functions was fundamental to the mechanism of hysteria: loss of integration was thought to engender fixed ideas (ideas fixes) and to lead to the development of a system totally isolated from the whole personality system. Janet also attempted to explain various mental disorders using an economic model. He referred to a loss of equilibration between psychological force and psychological tension. Thus, an unexpected emotional experience was conceived to cause a consumption of reserved psychological force, which was in turn followed by exhaustion associated with hysteric symptoms. Whereas most current researchers regard Janet as the first to study psychological trauma as a principal cause of dissociation, I feel it is important to note that he also emphasized the role of stigmata, i.e., permanent traits of hysteric patients, which were represented as a suggestibility and a tendency toward a narrowing of the consciousness field. Discussion about dissociation and its relation to trauma all but disappeared after Janet. However, during the Second World War and post-war period, some psychiatrists began to pay attention to two emerging phenomena: a high incidence of dissociative symptoms such as fugue and amnesia among combatants, and traumatic neurosis frequently observed among ex-inmates of concentration camps. In the 1970s, interest in dissociation and trauma was revived in different areas: the feminism movement was linked with concerns about child sexual abuse, public curiosity about multiple personalities was heightened by novels and movies, and recognition of posttraumatic stress disorder (PTSD) among Vietnam War veterans. In 1980, dissociative disorders were finally adopted as a diagnostic category in the official nomenclature of DSM-III. Although current research on dissociation is being carried out in various fields, two basic assumptions, reflected in the definition of DSM-IV, can be made. One is the "trauma-genic hypothesis," and the other is the great importance attached to multiple personality disorder (MPD). According to the predominantly held view, dissociation represents a reaction to early traumatic experience, especially sexual and physical abuse in childhood. In contrast, some authors argue that the causality of childhood traumatic experience has not been empirically confirmed, and other factors such as the influence of the environment and the predisposition of patients should be taken into consideration. MPD, which was originally described as an unusual phenomenon in classical literature, is currently thought to be a common type of dissociation. However, the reported rapid increase in the number of MPD patients in North America may be partially due to over-diagnosis and inclusion of iatrogenic cases. Significance is also given to MPD in respect to classification of dissociative phenomena. According to the widely held scheme of a "dissociative continuum," which ranges from normal experiences such as daydreams to pathological states, MPD is placed at the extreme end of the continuum. Furthermore, most researchers tend to classify MPD as the severest dissociative disorder due to chronic trauma. On this point, there seems to be confusion about "extremity" and "severity" of MPD. I conclude that the trauma-genic hypothesis of dissociation and the overemphasis placed on MPD should be reexamin

Adult↗
PubMed2003

Pathways to dissociation: intrafamilial versus extrafamilial trauma in juvenile delinquents.

Dissociation is postulated to occur as a function of particular types of child abuse or chronic abuse. Additionally, there is an ongoing controversy examining the perpetrator's relationship to the victim in the development of dissociation. In this study, reports of traumatic events experienced both in the family environment and in the community were used to examine the relationship between dissociative disorder as defined by DSM-IV (pathological dissociation), and dissociation as a defense mechanism. The first objective was to identify whether the site of the trauma or the quantity of trauma correlated more significantly with symptoms of dissociation. The second objective was to explore a potential correlation between topics that participants choose to disclose during a standardized Stress Inducing Speech Task (SIST), and symptoms of dissociation. The third objective was to examine the relationship between the age of occurrence, the duration of trauma, and symptoms of dissociation. Fifty-two delinquent juveniles completed measures (including the SCID-D, REM-71, CTQ, CTI, SIST) assessing traumatic experiences, psychopathological dissociation, and dissociation as defense mechanism. Blind raters scored the SIST for intrafamilial and extrafamilial trauma. The perpetrator's relationship to the victim, site of the trauma, quantity of the trauma, age of occurrence, and duration of the trauma were analyzed by descriptive statistics and Pearson partial correlations. Significant correlations were found between symptoms of pathological dissociation and intrafamilial trauma. Significant correlations were not found between extrafamilial trauma and pathological dissociation and dissociation as defense mechanism. All these correlations held constant the chronicity of traumas reported. The results obtained in this study through blind and independent assessment suggest that special trauma characteristics (i.e., childhood trauma perpetrated by a family member) rather than sheer cumulative effects of trauma may have greater implications for the development of pathological dissociation. The relationships to dissociation as a defense were much weaker.

Adolescent↗