Richard J. Loewenstein

Emotion Modulation in PTSD: Clinical and Neurobiological Evidence for a Dissociative Subtype

In this article, the authors present evidence regarding a dissociative subtype of PTSD, with clinical and neurobiological features that can be distinguished from nondissociative PTSD. The dissociative subtype is characterized by overmodulation of affect, while the more common undermodulated type involves the predominance of reexperiencing and hyperarousal symptoms. This article focuses on the neural manifestations of the dissociative subtype in PTSD and compares it to those underlying the reexperiencing/hyperaroused subtype. A model that includes these two types of emotion dysregulation in PTSD is described. In this model, reexperiencing/hyperarousal reactivity is viewed as a form of emotion dysregulation that involves emotional undermodulation, mediated by failure of prefrontal inhibition of limbic regions. In contrast, the dissociative subtype of PTSD is described as a form of emotion dysregulation that involves emotional overmodulation mediated by midline prefrontal inhibition of the same limbic regions. Both types of modulation are involved in a dynamic interplay and lead to alternating symptom profiles in PTSD. These findings have important implications for treatment of PTSD, including the need to assess patients with PTSD for dissociative symptoms and to incorporate the treatment of dissociative symptoms into stage-oriented trauma treatment.

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.

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.

Characteristics of patients with multiple personality and dissociative disorders on psychological testing.

We describe a new psychological testing procedure used on a consecutive series of 14 patients with multiple personality and dissociative disorders who met DSM-III-R and research criteria for dissociative disorders. Once dissociative phenomena were accounted for in testing, most patients displayed response patterns markedly different from those of schizophrenic and borderline patients. Patients showed striking variability on cognitive and projective tests, often related to posttraumatic intrusions. Rorschach protocols showed unusual thinking accompanied by psychological complexity and highly developed self-observing capacity. In contrast to classical conceptualizations about these patients, most subjects had personality profiles that were intellectualized, obsessive, and introversive, not histrionic or labile.

Distress in Response to and Perceived Usefulness of Trauma Research Interviews

ABSTRACT Because studying trauma often involves asking about upsetting experiences, it is important for researchers to study the effects of such interviews on research participants, particularly those who may be more vulnerable. In a study of psychiatric inpatients that included a structured interviews for PTSD and childhood physical and sexual assault experiences, participants rated how upsetting and how helpful or useful they found the interview. Of the 223 participants for whom we knew level of distress, 70% experienced relatively low levels of distress, and 51% found participation to be useful in some way. Level of upset was moderately to strongly related to levels of past trauma and current symptoms, while perceived usefulness was not significantly related to any experiences or symptoms.

Where are we going? An update on assessment, treatment, and neurobiological research in dissociative disorders as we move toward the DSM-5.

This article provides an overview of the process of developing the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) of the American Psychiatric Association with a focus on issues related to the trauma-related disorders, particularly the dissociative disorders (DD). We also discuss the highlights of research within the past 5 years in the assessment, treatment, and neurobiological basis of trauma disorders. Recent research shows that DD are associated with severe symptoms as well as a higher rate of utilization of mental health treatment compared with other psychiatric disorders. As a result, DD, like other complex posttraumatic disorders, exact a high economic as well as personal burden for patients and society. The latest research indicates that DD patients show a suboptimal response to standard exposure-based treatments for posttraumatic stress disorder as well as high levels of attrition from treatment. An emerging body of research on DD treatment, primarily of naturalistic and open trials, indicates that patients who receive specialized treatment that addresses their trauma-based, dissociative symptoms show improved functioning and reduced symptoms. Recent studies of the underlying neurobiological basis for dissociation support a model of excessive limbic inhibition in DD that is consistent with the phenomenology and clinical presentation of these patients. We are optimistic that the forthcoming DSM-5 will stimulate research on dissociation and the DD and suggest areas for future studies.

Multivariate prediction of posttraumatic symptoms in psychiatric inpatients

Based on a conceptual framework for the long-term effects of childhood abuse, this study examined the capacity of childhood family environment (caretaker dysfunction, neglect, perceived social support), violent abuse (physical and sexual), and individual variables (other abuse) to predict adult psychiatric symptoms of PTSD, dissociation, and depression. Complete interview data were obtained from 178 psychiatric inpatients who varied greatly on abuse status and severity. Results of multiple regressions of predictor variables onto the three outcome variables showed that the predictor variables accounted for 15% (for depression) to 42% (for PTSD) of the variance in these symptoms and that violent abuse uniquely accounted for a significant proportion of the variance in outcomes for all three of the symptom groups studied.

Dissociative Amnesia and Dissociative Fugue

In 1991, I published a comprehensive review of dissociative (psychogenic) amnesia (DA) and dissociative (psychogenic) fugue (DF), emphasizing the relationship of these conditions to overwhelming psychological trauma (Loewenstein, 1991b). Since the publication of that work, several additional studies have been published that support the basic premises of that review. Also, I have recently published a review of treatment of dissociative amnesia and dissociative fugue (Loewenstein, 1995). In addition, however, there has arisen an intense public and academic controversy about the validity of delayed adult recollections of childhood traumatic events, particularly those for which the individual reports prior amnesia (Loftus, 1993). Further, critics of the dissociation-trauma model have questioned whether DA for traumatic events ever occurs (McHugh, 1992). This chapter will update the prior review. In addition, however, I will discuss issues in the current controversy over the delayed recollection of traumatic events.

Dispelling Myths About Dissociative Identity Disorder Treatment: An Empirically Based Approach

Objective: Some claim that treatment for dissociative identity disorder (DID) is harmful. Others maintain that the available data support the view that psychotherapy is helpful. Method: We review the empirical support for both arguments. Results: Current evidence supports the conclusion that phasic treatment consistent with expert consensus guidelines is associated with improvements in a wide range of DID patients’ symptoms and functioning, decreased rates of hospitalization, and reduced costs of treatment. Research indicates that poor outcome is associated with treatment that does not specifically involve direct engagement with DID self-states to repair identity fragmentation and to decrease dissociative amnesia. Conclusions: The evidence demonstrates that carefully staged trauma-focused psychotherapy for DID results in improvement, whereas dissociative symptoms persist when not specifically targeted in treatment. The claims that DID treatment is harmful are based on anecdotal cases, opinion pieces, reports of damage that are not substantiated in the scientific literature, misrepresentations of the data, and misunderstandings about DID treatment and the phenomenology of DID. Given the severe symptomatology and disability associated with DID, iatrogenic harm is far more likely to come from depriving DID patients of treatment that is consistent with expert consensus, treatment guidelines, and current research.

Opposite brain emotion-regulation patterns in identity states of dissociative identity disorder: A PET study and neurobiological model

Imaging studies in posttraumatic stress disorder (PTSD) have shown differing neural network patterns between hypo-aroused/dissociative and hyper-aroused subtypes. Since dissociative identity disorder (DID) involves different emotional states, this study tests whether DID fits aspects of the differing brain-activation patterns in PTSD. While brain activation was monitored using positron emission tomography, DID individuals (n=11) and matched DID-simulating healthy controls (n=16) underwent an autobiographic script-driven imagery paradigm in a hypo-aroused and a hyper-aroused identity state. Results were consistent with those previously found in the two PTSD subtypes for the rostral/dorsal anterior cingulate, the prefrontal cortex, and the amygdala and insula, respectively. Furthermore, the dissociative identity state uniquely activated the posterior association areas and the parahippocampal gyri, whereas the hyper-aroused identity state uniquely activated the caudate nucleus. Therefore, we proposed an extended PTSD-based neurobiological model for emotion modulation in DID: the hypo-aroused identity state activates the prefrontal cortex, cingulate, posterior association areas and parahippocampal gyri, thereby overmodulating emotion regulation; the hyper-aroused identity state activates the amygdala and insula as well as the dorsal striatum, thereby undermodulating emotion regulation. This confirms the notion that DID is related to PTSD as hypo-aroused and hyper-arousal states in DID and PTSD are similar.