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PubMed2005

Phase-oriented treatment of structural dissociation in complex traumatization: overcoming trauma-related phobias.

The theory of structural dissociation of the personality proposes that patients with complex trauma-related disorders are characterized by a division of their personality into different prototypical parts, each with its own psychobiological underpinnings. As one or more apparently normal parts (ANPs), patients have a propensity toward engaging in evolutionary prepared action systems for adaptation to daily living to guide their actions. Two or more emotional parts (EPs) are fixated in traumatic experience. As EPs, patients predominantly engage action systems related to physical defense and attachment cry. ANP and EP are insufficiently integrated, but interact and share a number of dispositions of the personality (e.g., speaking). All parts are stuck in maladaptive action tendencies that maintain dissociation, including a range of phobias, which is a major focus of this article. Phase-oriented treatment helps patients gradually develop adaptive mental and behavioral actions, thus overcoming their phobias and structural dissociation. Phase 1, symptom reduction and stabilization, is geared toward overcoming phobias of mental contents, dissociative parts, and attachment and attachment loss with the therapist. Phase 2, treatment of traumatic memories, is directed toward overcoming the phobia of traumatic memories, and phobias related to insecure attachment to the perpetrator(s), particularly in EPs. In Phase 3, integration and rehabilitation, treatment is focused on overcoming phobias of normal life, healthy risk-taking and change, and intimacy. To the degree that the theory of structural dissociation serves as an integrative heuristic for treatment, it should be compatible with other theories that guide effective treatment of patients with complex dissociative disorders.

Adaptation, Psychological↗
PubMed2005

Peritraumatic dissociation and emotions as predictors of PTSD symptoms following childbirth.

UNLABELLED: The current study investigated the contributive role of perinatal dissociative and perinatal emotional responses to the development of PTSD symptoms following childbirth. METHOD: Using a prospective, longitudinal design, 140 women were studied who were followed from the first week after delivery to three months postpartum. RESULTS: Three women (2.1%) met criteria for PTSD and 21.4% reported a traumatic childbirth experience. Both perinatal negative emotional reactions and perinatal dissociative reactions were the predictors of PTSD symptoms at three months postpartum. The effect of perinatal dissociation, however, was partially mediated by perinatal emotional reactions. CONCLUSION: Posttraumatic stress disorder can be a consequence of the experience of childbirth. Women who reported high levels of negative emotions during and shortly after childbirth were more likely to develop PTSD symptoms than women who did not. Women who experienced an instrumental delivery and also reported higher levels of psychoform perinatal dissociation, were at higher risk than women who reported higher levels of perinatal dissociation during a spontaneous delivery. These findings add to the growing body of literature regarding traumatic childbirth and indicate that perinatal dissociative and emotional phenomena are associated with posttraumatic stress.

Adult↗
PubMed2006

The relationship between executive attention and dissociation in children.

Dissociation involves disruption in the usually integrated functions of consciousness, memory, identity, and perception. Recent research with adults suggests that dissociation is associated with alterations in attention. Little work, however, has examined the attentional correlates of dissociation in childhood. This study is the first to investigate the specificity of cognitive functions related to dissociation in children. Twenty-four 5- to 8-year-old foster children completed several subtests of the NEPSY: A Developmental Neuropsychological Assessment (Korkman, Kirk, & Kemp, 1998) in the Executive Functioning/ Attention domain. Foster caregivers completed the Child Dissociative Checklist (Bernstein & Putnam, 1986). Consistent with the adult literature, higher levels of childhood dissociation were associated with deficits in tasks requiring inhibition, but not with tasks requiring primarily planning, strategy, or multiple rule sets.

Attention↗
PubMed2002

Self-destructive behavior in patients with dissociative disorders.

Highrates of self-injury have been reported in patients with dissociative disorders, yet no prior study has directly compared these patients with other psychiatric patients. The present study assesses self-destructive behavior in a group of inpatients who have dissociative disorders compared to those who report few dissociative symptoms. These patients more frequently engage in self-destructive behaviors, use more methods of self-injury, and begin to injure themselves at an earlier age then patients who do not dissociate. Results have important implications for understanding the relationship between dissociation, childhood trauma, and self-injury and for assessment and treatment of patients with dissociative disorders.

Adult↗
PubMed1998

Dissociative identity disorder: an Australian series.

OBJECTIVE: Series of patients fulfilling diagnostic criteria for Dissociative Identity Disorder (DID), otherwise known as multiple personality disorder, have particularly been reported on in North America and increasingly in other countries. The present study investigated the trauma and past treatment histories, symptom profiles and dissociative phenomenology of 62 patients fulfilling diagnostic criteria for DID seen in Brisbane (Queensland, Australia). METHOD: From 1992, systematic assessments, including the Dissociative Experience Scale and the Dissociative Disorders Interview Schedule, were performed with a personal series of 57 patients with DID seen by one of the authors (WM) and five patients seen by the second author (JB). RESULTS: The histories of childhood trauma, the clinical profiles and dissociative indices of these patients closely approximate those described in series reported in other countries. CONCLUSIONS: Patients fulfilling diagnostic criteria for DID are regularly seen in Australian inpatient and outpatient settings. The dissociative symptomatology of the patients examined in the present study represents a significant component of a complex syndrome associated with a history of severe ongoing developmental trauma dating from early childhood.

Adolescent↗
PubMed2003

Dissociative experiences and anger proneness in late adolescent females with different attachment styles.

The study examined the relationships among dissociative experiences, anger proneness, and attachment styles in late adolescent females. One hundred sixty-two college students (mean age = 17.5 years) were assessed using the Dissociative Experience Scale (DES), the State-Trait Anger Expression Inventory (STAXI), and the Adult Attachment Questionnaire (AAQ), a self-report tool for assessing attachment styles (avoidant, secure, and ambivalent-resistant) in close relationships of youths and adults. Significant correlations were obtained between DES scores (total and factorial) and STAXI scores (State Anger, Trait Anger, Anger/In, and Anger/Expression), confirming in a nonclinical sample the connection between anger proneness and dissociation described in patients with dissociative disorders. Insecure females, particularly ambivalent ones, scored higher on the DES, supporting van der Kolk's hypothesis of an inverse relationship between secure attachment and dissociative tendency. Moreover, insecurely attached females showed more anger proneness, with some differences between ambivalent and avoidant types. Further research should be conducted to examine these relationships in males, as well as to clarify the role of insecure attachment in anger management and the recourse to dissociation in late adolescence as a protective response to trauma and emotional distress.

Adolescent↗
PubMed2004

Trauma and dissociation in psychiatric outpatients.

BACKGROUND: We investigated the prevalence of exposure to traumatic events, the prevalence of post-traumatic suffering and dissociative symptoms, and the relationship between type of trauma and dissociation in a large sample of outpatient adults (ages 18-65) seeking treatment at an urban ambulatory mental health clinic in Jerusalem (N = 298). METHOD: Study participants completed self-report measures regarding trauma history, post-traumatic symptoms of intrusion and avoidance phenomena, and both psychological and somatic dissociative phenomena. RESULTS: 98% of our sample reported experiencing at least one lifetime traumatic event, 83% of subjects who completed the Impact of Events Scale reported high levels of intrusion and avoidance symptoms, and 15% of the sample reported high levels of dissociative phenomena. Elevated dissociation was associated with physical and sexual abuse, particularly early childhood abuse, as well as increased prevalence of lifetime traumatic events. Diagnoses did not reflect the high levels of post-traumatic and dissociative symptoms. CONCLUSIONS: Our findings indicate the need for increased awareness and improved screening of traumatic exposure and its psychological impact upon psychiatric outpatients.

Adult↗
PubMed2004

Relationship between alexithymia, dissociation and anxiety in psychiatric outpatients from Turkey.

Several studies have examined the relationship between dissociation and alexithymia. In this study, the objective was to investigate whether there was a relationship between alexithymia, dissociation and state and trait anxiety in psychiatric outpatients. The evaluations of psychiatric outpatients (n=154) were based on the Toronto Alexithymia Scale, the Dissociative Experiences Scale and the State and Trait Anxiety Index. The data were analyzed using chi2 test and multiple covariance analyses. Subjects with alexithymia (46.8%) were significantly less educated and showed higher state and trait anxiety. The mean Toronto Alexithymia Scale total score of the female and male patients was similar. The mean Dissociative Experiences Scale score of the study group was 10.8 (sd=9.8, ranged 0 to 45). A multivariate analysis of covariance showed that state and trait anxiety was a significant covariant for the Toronto Alexithymia Scale-Difficulty Identifying Feelings subscale. Only the trait anxiety was a significant covariant for the Toronto Alexithymia Scale-Difficulty Expressing Feelings subscale. The overall main effect of dissociation was not significant on the Toronto Alexithymia Scale total and subscales. These data suggest that dissociation is fundamentally a different construct from alexithymia, while state and trait anxiety are closely related to alexithymia.

Adult↗
PubMed2004

Dissociation and childhood abuse history in epileptic and pseudoseizure patients.

The aim of this study was to examine dissociative experiences, childhood abuse and anxiety in epileptic and pseudoseizure female patients. Thirty-three patients with pseudoseizures and thirty patients with epilepsy were recruited from Cumhuriyet University Hospital Psychiatry and Neurology Units. We assessed each participant using the Dissociative Experiences Scale, the Clinician-Administered Dissociative States Scale and the Childhood Abuse and Neglect Questionnaire. The female patients with pseudoseizures showed significantly higher levels of dissociative experiences and childhood trauma. Epileptic female patients showed higher levels of anxiety. The significantly higher incidence of dissociative experiences and childhood trauma in the patients with pseudoseizures makes a case for dissociation in the pathogenesis of these seizures.

Adolescent↗
PubMed2006

[The relationship between traumatic experiences and dissociative phenomena].

BACKGROUND: Intuitively we are convinced that there must be a causal relationship between traumatic experiences and dissociation. However, although the theory is both elegant and attractive, the existence of a direct causal link between trauma and dissociation is open to question. Available studies on this theme have methodological shortcomings. AIM: To obtain more insight into the frequency with which psychiatric patients have undergone traumatic experiences and to find out more about the relationship between theses experiences and dissociative phenomena. METHOD: Over a period of two years new outpatients attending psychiatric clinics completed questionnaires about their past life and mental health; in these questionnaires they gave information about traumatic experiences, dissociative phenomena, psychological symptoms and psychological functioning. RESULTS: Only 38 of the 351 patients who completed the questionnaire stated that they had never had any traumatic experiences. A relatively large number of patients mentioned that they had experienced emotional deprivation in their family of origin. The correlation coefficient between traumatic experiences and the scores for dissociative phenomena was 0.30. CONCLUSION: In view of the weak positive correlation between traumatic experiences and dissociative phenomena the hypothesis of a linear causal relationship seems unlikely. It is possible that the relationship is based partly on the poorer general psychological functioning that follows exposure to traumatic experiences.

Adolescent↗
PubMed2006

[Dissociative symptoms and sleep].

There is a widespread view among psychiatrists that dissociative experiences such as depersonalisation, derealisation, absorption, and psychogenic amnesia have a traumatic etiology. This view is subjected to a critical evaluation. We also discuss an alternative interpretation namely that dissociative experiences are caused by a labile sleep-wake rhythm. We evaluated this alternative view in two exploratory studies. In study 1 we looked at the relationship between the Dissociative Experience Scale (DES) and the Iowa Sleep Experiences Survey (ISES) and in study 2, we checked this relationship when the response bias was controlled for. Dissociative experiences (measured with the DES) correlated with the ISES. The correlation between DES and ISES remained completely intact even when we controlledfor response bias. Our findings show that dissociative symptoms are associated with typical sleep experiences such as nightmares and strange dreams. The association is not the by-product of the positive response bias which generally characterises persons with dissociative symptoms.

Circadian Rhythm↗
PubMed1995

[The dialectic of the obsessionality and the dissociativity: toward a psychopathology of binge-eating].

Binge-eating is one of the most paradoxical phenomena in the symptomatology of anorexia nervosa and bulimia nervosa. The patients seem to be struggling to control their eating behaviors as strictly as possible, and at the same time, they repeat chaotic patterns of binge-eating. The author investigated the descriptive psychopathology of binge-eating in this paper. The author recognized the impulsive nature of binge-eating at first, and compared it with the clinical features of so-called impulse control disorders, such as kleptomania, trichotillomania, and so on. According to the literature review, most impulse control disorders tended to show high coincidence with eating disorders. The mode of the coincidence and the alternation of the symptoms suggested the common psychopathologies between eating disorders and impulse control disorders. The author then inquired into their common psychopathologies, and revealed characteristic features which could be formulated as dissociative. The study of the concept of dissociation proved that this formulation was not only valid, but also useful in understanding eating disorders clinically and theoretically. Binge-eating could be regarded as a manifestation of dissociative pathology. The author inquired further into the psychopathologies of eating disorders and impulse control disorders, and revealed obsessional features in these disorders. Though some investigators regarded the symptoms of eating disorders as compulsive behaviors and considered that eating disorders were variants of obsessive-compulsive disorder, the author pointed out some descriptive differences between them. Nevertheless, the obsessionality formed an important basis of the psychopathology of binge-eating. Finally, the author discussed the relationship between the obsessionality and the dissociativity in eating disorders. These two features were reciprocal factors in mental activity, and were forming dialectical dynamism in general psychological functioning. In anorexia nervosa and bulimia nervosa, the opposition between two factors was morbidly rigid and their sublation could not occur. Though the obsessional and the dissociative features of binge-eating were opposite phenomena, it was important to comprehend them as an incorporated psychopathology. The conceptualization of the dialectic of the obsessionality and the dissociativity could also be useful in understanding other psychopathological phenomena such as addiction and splitting.

Adult↗
PubMed1999

Determination of dissociation constants of amino acids by capillary zone electrophoresis.

A method is proposed for the determination of dissociation constants of amino acids by capillary zone electrophoresis. According to the dissociation equilibrium of amino acids and the basic theory of electrophoresis, the nonlinear relationship between the pH value of the buffer and the effective electrophoretic mobilities of the analyte was obtained. The dissociation constants can be calculated from the pH values and the corresponding effective electrophoretic mobilities using the program written in C++. The dissociation constants, pKa1 and pKa2, of 11 kinds of amino acids were determined successfully by the proposed method. The determined dissociation constants were compared with values in the literature; the differences between them are in the range of -0.03 to 0.06. No significant differences were observed between the determined dissociation constants and the corresponding literature values.

Amino Acids↗
PubMed1996

Subunit dissociations in natural and recombinant hemoglobins.

A precise and rapid procedure employing gel filtration on Superose-12 to measure the tetramer-dimer dissociation constants of some natural and recombinant hemoglobins in the oxy conformation is described. Natural sickle hemoglobin was chosen to verify the validity of the results by comparing the values with those reported using an independent method not based on gel filtration. Recombinant sickle hemoglobin, as well as a sickle double mutant with a substitution at the Val-6(beta) receptor site, had approximately the same dissociation constant as natural sickle hemoglobin. Of the two recombinant hemoglobins with amino acid replacements in the alpha 1 beta 2 subunit interface, one was found to be extensively dissociated and the other completely dissociated. In addition, the absence of an effect of the allosteric regulators DPG and IHP on the dissociation constant was demonstrated. Thus, a tetramer dissociation constant can now be determined readily and used together with other criteria for characterization of hemoglobins and their interaction with small regulatory molecules.

Allosteric Regulation↗
PubMed1998

Metmyoglobin/fluoride: effect of distal histidine protonation on the association and dissociation rate constants.

The kinetics of formation and dissociation of the horse metmyoglobin/fluoride complex has been investigated between pH 3.4 and 11. The ionic strength dependence of the reaction has been measured at integral pH values between pH 5 and 10. Hydrofluoric acid, HF, binds to metmyoglobin with a rate constant of (4.7 +/- 0. 7) x 10(4) M-1 s-1. An apparent ionization in metmyoglobin with a pKa of 4.4 +/- 0.5 influences the rate of HF binding and is attributed to the distal histidine, His-64. Protonation of His-64 increases the HF binding rate by a factor of 2.6. The fluoride anion, F-, binds to metmyoglobin with a rate constant of (5.6 +/- 1.4) x 10(-2) M-1 s-1, about 10(6) times slower than HF. Binding of either HF or F- to hydroxymetmyoglobin cannot be detected. Protonation of the distal histidine facilitates HF dissociation from the metmyoglobin/fluoride complex. HF dissociates with a rate constant of 1.9 +/- 0.3 s-1. The fluoride anion dissociates 2000 times more slowly, with a rate constant of (8.7 +/- 1.6) x 10(-4) s-1. The apparent pKa for His-64 ionization in the fluorometmyoglobin complex is 5.7 +/- 0.1. The association and dissociation rate constants are relatively independent of ionic strength with secondary kinetic salt effects sufficient to account for the ionic strength variation of both, consistent with the idea that association and dissociation of neutral HF dominate the kinetics of fluoride binding to metmyoglobin.

Animals↗
PubMed1993

Investigations of ligand association and dissociation rates in the "open" and "closed" states of myoglobin.

Kinetic and Raman spectroscopic studies are combined to analyze ligand association and dissociation rates as a function of pH in aqueous solutions of myoglobin. A double-pulse flash photolysis protocol is used to kinetically select a rapidly rebinding (open pocket) fraction of the myoglobin ensemble and determine the timescale for averaging (approximately 1 to 10 microseconds) between the "open" and "closed" distal pocket protein conformations. Since this timescale is fast compared to the rate of ligand migration from the solution to the heme pocket (approximately 10(-4)s), a time-averaged population analysis, rather than a superposition of states, can be used to describe the ligand association and dissociation kinetics. Raman spectroscopy provides the relative populations of the open and closed distal pocket states as a function of pH which, in parallel with kinetics measurements, are used to determine the rates for ligand association and dissociation specific to these states. In aqueous solution at 293 K (1 mM CO) we find kon0 = 5.6 x 10(3) s-1, koff0 = 8.5 x 10(-2) s-1 for the open state and kon1 = 5.0 x 10(2) s-1, koff1 = 1.3 x 10(-2) s-1 for the closed state. The order of magnitude increase in the dissociation and association rates of the open form suggests that it may play a significant role in the ligand binding process, even though it comprises only approximately 5% of the time-averaged population at pH 7. For oxygen binding at 293 K (1.36 mM O2) we find kon0 = 4.6 x 10(4) s-1, koff0 approximately 10(4 +/- 2) s-1 for the open state and kon1 = 2.0 x 10(4) s-1, koff1 = 13 s-1 for the closed state. The dramatic increase in the dissociation rate of the open form is probably due to the loss of the hydrogen bond with the distal histidine, which stabilizes the bound O2 in the closed state. Overall, these results demonstrate that the open conformation plays a significant role in determining the ligand association and dissociation rates and suggest that environmentally induced modulations of the open population could be used as a biomolecular control mechanism for the uptake and delivery of oxygen in muscle cells.

Carbon Monoxide↗
PubMed1984

Dissociation of peptidyl-tRNA from ribosomes is perturbed by streptomycin and by strA mutations.

Peptidyl-tRNA may dissociate preferentially from ribosomes during protein synthesis when it is inappropriate to, does not correctly complement, the messenger RNA. To test this idea, growing cultures of Escherichia coli were treated with streptomycin to increase the frequency of errors during protein synthesis. Since the treated cells had a temperature-sensitive peptidyl-tRNA hydrolase and could not destroy dissociated peptidyl-tRNA, it was possible to measure the rate of its accumulation after raising the temperature to non-permissive conditions. Both low and high doses of streptomycin enhanced the rate of dissociation and accumulation of peptidyl-tRNA. The rank order of rates of dissociation/accumulation of various isoaccepting tRNA families was not significantly altered by the drug treatment. We concluded that streptomycin stimulated a normal pathway for dissociation of peptidyl-tRNA. Two streptomycin- resistant strains of E. coli had higher rates of dissociation of peptidyl-tRNA than did their sensitive parent strain. When treated with high doses of the drug, the resistant strains showed slightly reduced rates of dissociation of peptidyl-tRNA. These results were interpreted in terms of a two state, two site model for protein synthesis: streptomycin enhances the binding of aminoacyl-tRNA to a tight state of the ribosome A site; the strA mutation enhances translocation to a loose state of the ribosome P site.

Bacterial Proteins↗
PubMed1992

An analysis of the role of collagenase and protease in the enzymatic dissociation of the rat pancreas for islet isolation.

Crude Clostridium histolyticum collagenase is widely used for the enzymatic degradation of pancreatic extracellular matrix in order to isolate the islets of Langerhans. The variable enzymatic composition of crude collagenases is a critical issue which contributes to the poor reproducibility of islet isolation procedures. In this study, the separate contributions of collagenase and protease to the islet isolation process were analysed by testing various combinations of purified collagenase and purified protease in rat pancreas dissociations under conditions which eliminated all other proteolytic activity. Under these conditions, complete tissue dissociation by purified collagenase required 99 +/- 10 min, whereas increasing amounts of protease progressively reduced this time to a minimum of 36 +/- 1 min. Histochemical analysis of the dissociation process showed that protease enhanced the degradation of all four major components of the extracellular matrix: collagen was degraded more completely, while proteoglycans, glycoproteins and elastin were degraded at a higher rate. Pancreas dissociation under the present, strictly controlled conditions resulted in a high yield of viable islets: 4.2-5.0 microliters islet tissue volume (3,300-3,800 islets) were isolated per g pancreas in the presence of a high or low protease concentration, respectively. Prolonged dissociation in the presence of protease resulted in a dramatic decrease in islet yield which correlated with the observation that the enzyme accelerated islet disintegration. It is concluded that the collagenase-induced dissociation of the extracellular matrix is facilitated by protease. Our study shows that high yields of viable islets can be obtained under controlled enzymatic conditions, provided that the exposure of islets to protease is limited.

Animals↗