Eve B. Carlson

Types of dissociation and dissociative types: A taxometric analysis of dissociative experiences

This article examined evidence for dimensional and typological models of dissociation. The authors reviewed previous research with the Dissociative Experiences Scale (DES; E. B. Bernstein-Carlson & F. W. Putnam, 1986) and note that this scale, like other dissociation questionnaires, was developed to

Patterns of dissociation in clinical and nonclinical samples

Research has consistently found elevated mean dissociation scores in particular diagnostic groups. In this study, we explored whether mean dissociation scores for different diagnostic groups resulted from uniform distributions of scores within the group or were a function of the proportion of highly dissociative patients that the diagnostic group contained. A total of 1566 subjects who were psychiatric patients, neurological patients, normal adolescents, or normal adult subjects completed the Dissociative Experience Scale (DES). An analysis of the percentage of subjects with high DES scores in each diagnostic group indicated that the diagnostic groups mean DES scores were a function of the proportion of subjects within the group who were high dissociators. The results contradict a continuum model of dissociation but are consistent with the existence of distinct dissociative types.

Development and validation of a measure of adolescent dissociation: the Adolescent Dissociative Experiences Scale.

This study describes the initial reliability and validity data on the Adolescent Dissociative Experiences Scale (A-DES), a screening measure for pathological dissociation during adolescence. The A-DES showed good scale and subscale reliability, and, as hypothesized, increased scores were associated with reported trauma in a patient population. A-DES scores were able to distinguish dissociative disordered adolescents from a normal sample and from a patient sample with a variety of diagnoses.

Evaluation of the Evidence for the Trauma and Fantasy Models of Dissociation

The relationship between a reported history of trauma and dissociative symptoms has been explained in 2 conflicting ways. Pathological dissociation has been conceptualized as a response to antecedent traumatic stress and/or severe psychological adversity. Others have proposed that dissociation makes individuals prone to fantasy, thereby engendering confabulated memories of trauma. We examine data related to a series of 8 contrasting predictions based on the trauma model and the fantasy model of dissociation. In keeping with the trauma model, the relationship between trauma and dissociation was consistent and moderate in strength, and remained significant when objective measures of trauma were used. Dissociation was temporally related to trauma and trauma treatment, and was predictive of trauma history when fantasy proneness was controlled. Dissociation was not reliably associated with suggestibility, nor was there evidence for the fantasy model prediction of greater inaccuracy of recovered memory. Instead, dissociation was positively related to a history of trauma memory recovery and negatively related to the more general measures of narrative cohesion. Research also supports the trauma theory of dissociation as a regulatory response to fear or other extreme emotion with measurable biological correlates. We conclude, on the basis of evidence related to these 8 predictions, that there is strong empirical support for the hypothesis that trauma causes dissociation, and that dissociation remains related to trauma history when fantasy proneness is controlled. We find little support for the hypothesis that the dissociation-trauma relationship is due to fantasy proneness or confabulated memories of trauma.

Cross‐cultural response to trauma: A study of traumatic experiences and posttraumatic symptoms in cambodian refugees

Despite a growing literature of cross-cultural research on mental illness, little is known about the universality of most psychiatric disorders. This study was designed to determine whether people from a very different culture have the same symptoms in response to traumatic experiences as do trauma survivors in the United States. We were also interested to find out if the severity of the current symptoms is related to the amount of trauma experienced. Furthermore, we gathered information about the perceived severity of traumatic experiences among refugees. Fifty Cambodian refugees living in the U.S. were asked about their traumatic experiences and their current symptoms of posttraumatic stress, dissociation, depression, and anxiety. High levels of all symptoms were found along with statistically significant relationships between each symptom measure and the amount of trauma experienced. We conclude that the basic symptom picture in this group was similar to that observed in U.S. trauma survivors.

A Conceptual Framework for the Impact of Traumatic Experiences

This conceptual framework for the effects of traumatic experiences addresses what makes an experience traumatic, what psychological responses are expected following such events, and why symptoms persist after the traumatic experience is over. Three elements are considered necessary for an event to be traumatizing: The event must be experienced as extremely negative, uncontrollable, and sudden. The initial core responses to trauma include reexperiencing and avoidance symptoms that occur across four modes of experience. Explanations of how each response is theoretically linked to traumatic events are offered to clarify how the responses reflect the natural human response to uncontrollable, negative, and sudden events. The framework delineates the behavioral learning and cognitive processes that elucidate the persistence of the initial response to trauma. Five factors are proposed that influence the response to trauma, including biological factors, developmental level at the time of trauma, severity of the stressor, social context, and prior and subsequent life events. Finally, secondary and associated responses to trauma are discussed that are common across many types of traumatic experience. These include depression, aggression, substance abuse, physical illnesses, low self-esteem, identity confusion, difficulties in interpersonal relationships, and guilt and shame.

Basal and Dexamethasone Suppressed Salivary Cortisol Concentrations in a Community Sample of Patients with Posttraumatic Stress Disorder

BACKGROUND Posttraumatic stress disorder (PTSD) has been associated with lower concentrations of cortisol and enhanced suppression of cortisol by dexamethasone, although discrepancies exist among reports. The objective of the study was to determine the pattern of cortisol responses in patients seeking treatment for PTSD resulting from a variety of traumatic experiences and to test whether cortisol responses are significantly related to childhood trauma, severity of symptoms, or length of time since trauma. METHODS Salivary cortisol was measured at 8 AM, 4 PM, and 10 PM on 2 consecutive days before and after a 10 PM dose of .5 mg dexamethasone in 17 psychotropic medication and substance-free subjects with PTSD and 17 matched control subjects. RESULTS Repeated-measures analysis of variance (ANOVA) of the baseline salivary cortisol concentrations demonstrated a significant effect for group with higher concentrations in the PTSD group but no significant differences in responses to dexamethasone. The presence of childhood abuse did not significantly affect salivary cortisol concentrations, and there was no correlation between predexamethasone cortisol and either the severity of PTSD symptoms or the time since the index trauma. CONCLUSIONS Neither low basal concentrations nor enhanced suppression of cortisol are consistent markers of a PTSD diagnosis.

Psychometric study of a brief screen for PTSD: assessing the impact of multiple traumatic events.

Most measures of posttraumatic stress disorder (PTSD) symptoms are limited in that they focus on a single traumatic event and cannot be used to assess symptoms in persons who report no traumatic events. The utility of the brief PTSD measures that do not key to a sin-gle trauma is limited by lengthiness and high reading levels. The Screen for Posttraumatic Stress Symptoms (SPTSS) is a brief, self-report screening instrument for PTSD symptoms that overcomes these limitations by assessing PTSD symptoms using a low reading level and without keying them to a specific traumatic event. In a sample of 136 psychiatric inpatients, the SPTSS showed good internal consistency, a high sensitivity rate, and a moderate specificity rate. The concurrent and construct validity of the SPTSS were supported by strong correlations with symptom and trauma experience measures and by comparisons of SPTSS scores of groups with different trauma histories.

Acute Stress Disorder Revisited

Acute stress disorder (ASD) was introduced into the Diagnostic and Statistical Manual (DSM) taxonomy in 1994 to address the lack of a specific diagnosis for acute pathological reactions to trauma and the role that dissociative phenomena play both in the short- and long-term reactions to trauma. In this review, we discuss the history and goals of the diagnosis and compare it with the diagnoses of acute stress reaction, combat stress reaction, and posttraumatic stress disorder (PTSD). We also evaluate the research on the validity and limitations of ASD as a diagnosis, the relationship between peritraumatic dissociation and other symptomatology, the extent to which PTSD is predicted by previous ASD or peritraumatic dissociation, and other important issues such as impairment and risk factors related to ASD. We conclude with our recommendations for changes in DSM-5 criteria and the development of more sophisticated research that considers ASD as but one of two or possibly three common acute posttraumatic syndromes.

Distinguishing PTSD, Complex PTSD, and Borderline Personality Disorder: A latent class analysis

Background There has been debate regarding whether Complex Posttraumatic Stress Disorder (Complex PTSD) is distinct from Borderline Personality Disorder (BPD) when the latter is comorbid with PTSD. Objective To determine whether the patterns of symptoms endorsed by women seeking treatment for childhood abuse form classes that are consistent with diagnostic criteria for PTSD, Complex PTSD, and BPD. Method A latent class analysis (LCA) was conducted on an archival dataset of 280 women with histories of childhood abuse assessed for enrollment in a clinical trial for PTSD. Results The LCA revealed four distinct classes of individuals: a Low Symptom class characterized by low endorsements on all symptoms; a PTSD class characterized by elevated symptoms of PTSD but low endorsement of symptoms that define the Complex PTSD and BPD diagnoses; a Complex PTSD class characterized by elevated symptoms of PTSD and self-organization symptoms that defined the Complex PTSD diagnosis but low on the symptoms of BPD; and a BPD class characterized by symptoms of BPD. Four BPD symptoms were found to greatly increase the odds of being in the BPD compared to the Complex PTSD class: frantic efforts to avoid abandonment, unstable sense of self, unstable and intense interpersonal relationships, and impulsiveness. Conclusions Findings supported the construct validity of Complex PTSD as distinguishable from BPD. Key symptoms that distinguished between the disorders were identified, which may aid in differential diagnosis and treatment planning.