Dissociation in the laboratory: a comparison of strategies

Several methods for inducing dissociation in the laboratory were examined in a sample of 78 undergraduate students. Participants scoring high or low on the Dissociative Experiences Scale participated in three dissociation challenge conditions: (a) dot-staring task, (b) administration of pulsed photic and audio stimulation and (c) stimulus deprivation. Participants recorded their dissociative experiences both before and after each of the three challenge conditions. Across conditions, high DES participants reported significantly more dissociative sensations than low DES participants, even after controlling for pre-challenge dissociation. Moreover, regardless of DES status, pulsed photo and audio stimulation produced the greatest level of dissociative symptoms. The findings suggest that the induction of dissociative symptoms in a nonclinical sample is easily accomplished in the laboratory and that those who report more dissociative symptoms in their day-to-day life exhibit more pronounced dissociative symptoms when undergoing dissociative challenge in the laboratory. Implications for the study and treatment of dissociative symptoms are discussed.     

The relationship between traumatic experiences, dissociation, and borderline personality pathology among male forensic patients and prisoners

In the present study the relationship between traumatic experiences, dissociation, and borderline personality disorder pathology is examined in a group of 39 male forensic patients and 192 male prisoners. Sexual and emotional abuse are significantly more common among forensic patients than among prisoners. Patients also report a broader range of different kinds of traumas. Prisoners report significantly more dissociative symptoms. Analyses of the relationship of type of trauma on the one hand and dissociation and borderline personality pathology on the other show that sexual abuse is significantly associated with borderline personality pathology but not with dissociation among the patients. In the prison sample these associations are found only for familial but not extrafamilial sexual abuse. When the subjects are grouped on account of presence or absence of a borderline personality disorder, highly significant differences on dissociation are found between both groups. The results from this study lend support to the hypothesis that sexual abuse is not related to dissociative symptoms but merely to borderline personality pathology. Because most subjects in this study are not patients, these findings are not likely to be confounded by false memories of traumatic events that are recovered by psychotherapy. Furthermore, dissociative symptoms are found to be related to borderline personality pathology and not to the experience of traumatic events.     

Factorial structure and psychometric properties of the French adaptation of the Dissociative Experiences Scale (DES) in non-clinical participants

IntroductionThe Dissociative Experiences Scale (DES) is a widely used instrument for assessing dissociation. However, there is disagreement regarding the internal structure of the DES and scores tend to be highly skewed.ObjectiveThe present study was designed to test the psychometric properties of a French version of the DES in non-clinical participants, in addition to applying a response scale as recommended by Wright and Loftus (1999) in order to resolve the problem of skewed scores.ResultsExploratory and confirmatory factor analysis (computed in two independent samples) suggested a two-factor solution, which seem to represent two forms of dissociation (“automatic pilot” related dissociation episodes and “defensive” dissociation episodes). Results also revealed high internal consistency, and satisfactory results in terms of skewness and floor effects. Finally, significant associations with other measures (anxiety, depression, traumatic experiences) indicate good concurrent validity.ConclusionsThis study offers evidence that the present version of the French adaptation of the DES reveals good psychometric properties. Analyses of the internal structure of the DES suggest that two types of dissociative experiences are being measured: automatic pilot-related dissociation episodes (e.g., associated with different types of cognitive failures) and defensive dissociation episodes that may act as defensive mechanisms, especially in persons who have been traumatized (e.g., the avoidance of a memory related to a traumatic event).     

Differential Predictors of Transient Stress Versus Posttraumatic Stress Disorder: Evaluating Risk Following Targeted Mass Violence

Schools have become a common incident site for targeted mass violence, including mass shootings. Although exposure to mass violence can result in significant distress, most individuals are able to fully recover over time, while a minority develop more pervasive pathology, such as PTSD. The present study investigated how several pre- and posttrauma factors predict posttraumatic stress symptoms (PTSS) in both the acute and distal aftermath of a campus mass shooting using a sample with known levels of pretrauma functioning (N = 573). Although the largest proportion of participants evidenced resilience following exposure to the event (46.1%), many reported high rates of PTSS shortly after the shooting (42.1%) and a smaller proportion (11.9%) met criteria for probable PTSD both in the acute and more distal aftermath of the event. While several preshooting factors predicted heightened PTSS after the shooting, prior trauma exposure was the only preshooting variable shown to significantly differentiate between those who experienced transient versus prolonged distress. Among postshooting predictors, individuals reporting greater emotion dysregulation and peritraumatic dissociative experiences were over four times more likely to have elevated PTSS 8 months postshooting compared with those reporting less dysregulation and dissociative experiences. Individuals with less exposure to the shooting, fewer prior traumatic experiences, and greater satisfaction with social support were more likely to recover from acute distress. Overall, results suggest that, while pretrauma factors may differentiate between those who are resilient in the aftermath of a mass shooting and those who experience heightened distress, several event-level and posttrauma coping factors help distinguish between those who eventually recover and those whose PTSD symptoms persist over time.     

Dissociative alterations in body image among individuals reporting out-of-body experiences: a conceptual replication

A conceptual replication of the link between self-reported dissociative alterations in body-image under experimental conditions and the reporting of prior out-of-body experiences in a recent data set was undertaken. Also examined was whether this relationship would hold for experiences reported during the experimental context and whether it is independent of self-reported New Age belief. Data from mostly undergraduates (N= 40; M age = 33.5, SD = 12.5; 27 women) in a mirror-gazing study were retrospectively analyzed. The 9 individuals who reported prior out-of-body experiences, relative to those 31 who did not, exhibited significantly greater self-reported dissociative alterations in body-image during the mirror-gazing task, even when the influence of scores on New Age belief was controlled for statistically. The same differential relationship was not found between 6 individuals who did and 34 who did not report out-of-body experiences during the task.     

Measuring dissociation: comparison of alternative forms of the dissociative experiences scale

The dissociative experiences scale (DES), developed by Bernstein and Putnam (1986), is commonly used to measure dissociation in clinical populations. It is often used with nonclinical populations to assess how levels of dissociation covary with other psychometric measures. When it is used with nonclinical populations, problems arise because the resulting scores can show severe floor effects and often are highly skewed. To remedy these problems, we developed alternative ways of measuring self-reported dissociative experiences. A form of the DES in which people were required to rate how often they have each of 28 experiences compared with other people was superior in avoiding problems of floor effects and skewness. We discuss situations in which this alternative, which we call DES C, is preferred.     

The causal link between self-reported trauma and dissociation: a critical review

The idea that traumatic experiences cause dissociative symptoms is a recurrent theme in clinical literature. The present article summarizes evidence that cast doubts on the commonly voiced view that the connection between self-reported trauma and dissociation is a simple and robust one. It is argued that: (1) the correlations between self-reported traumatic experiences and dissociative symptoms reported in the literature are, at best, modest; (2) other factors may act as a third variable in the relationship between trauma and dissociation; and (3) high scores on the Dissociative Experiences Scale are accompanied by fantasy proneness, heightened suggestibility, and susceptibility to pseudomemories. These correlates of dissociation may promote a positive response bias to retrospective self-report instruments of traumatic experiences. Thus, the possibility that dissociation encourages self-reported traumatic experiences rather than vice versa merits investigation. While attractive, simple models in which trauma directly causes dissociation are unlikely to be true.     

Traumatic memories of war veterans: not so special after all

Several authors have argued that traumatic experiences are processed and remembered in a qualitatively different way from neutral events. To investigate this issue, we interviewed 121 Croatian war veterans diagnosed with posttraumatic stress disorder (PTSD) about amnesia, intrusions (i.e., flashbacks and nightmares), and the sensory qualities of their most horrific war memories. Additionally, they completed a self-report scale measuring dissociative experiences. In contrast to what one would expect on the basis of theories emphasizing the special status of traumatic memories, amnesia, and high frequency intrusions were not particularly typical for our sample of traumatized individuals. Moreover, traumatic memories were not qualitatively different from neutral memories with respect to their stability and sensory qualities. The severity of PTSD symptoms was not significantly correlated with dissociative experiences. Our findings do not support the existence of special memory mechanisms that are unique to experiencing traumatic events.     

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.     

Childhood Abuse,Head Injuries,and Use of Medical Emergency Services in People with Severe Mental Illness

People with severe mental illness (SMI) report high rates of traumatic experiences. This study analyzes data collected from 183 people diagnosed with SMI on reports of childhood trauma, head injuries, and emergency room (ER) services. More than half the cohort (56.7%) reported 3 to 7 cooccurring categories of childhood abuse (CAB). People who reported 6 and 7 categories of CAB had a 5-fold risk of experiencing a head injury. If they have used the ER for reasons other than psychiatric illness they endorse more traumatic experiences in their childhood when compared to those who did not. People with SMI and cooccurring CAB experiences might be predisposed to a higher risk of head injuries and more frequent use of the ER.     

Do traumatic events influence the clinical expression of compulsive hoarding?

Traumatic experiences have been posited as one potential catalyst for the abrupt onset of obsessive-compulsive symptoms including compulsive hoarding. To determine whether traumatic life events (TLEs) might influence the expression of compulsive hoarding in obsessive-compulsive disorder (OCD), interview responses to the Posttraumatic Stress Disorder module of the Structured Clinical Interview for DSM-IV (SCID) were examined in 180 individuals with OCD. Compared to individuals with OCD who did not meet criteria for hoarding, participants classified as hoarders (24% of the sample) were significantly more likely to have reported at least one TLE in their lifetime. Patients who met criteria for hoarding and who had also experienced TLEs had significantly greater hoarding symptom severity than those hoarders not exposed to trauma. This association was found to be robust. That is, the relationship between TLEs and hoarding symptom severity was not better accounted for by age, age of OCD onset, depressive symptoms, general OCD symptomatology, or mood and anxiety comorbidity. Closer examination revealed that the clutter factor of compulsive hoarding (and not difficulty discarding or acquisitioning) was most strongly associated with having experienced a traumatic event.     

Fantasy proneness, but not self-reported trauma is related to DRM performance of women reporting recovered memories of childhood sexual abuse

Extending a strategy previously used by , we administered a neutral and a trauma-related version of the Deese-Roediger-McDermott paradigm to a sample of women reporting recovered (n=23) or repressed memories (n=16) of childhood sexual abuse (CSA), women reporting having always remembered their abuse (n=55), and women reporting no history of abuse (n=20). We found that individuals reporting recovered memories of CSA are more prone than other participants to falsely recalling and recognizing neutral words that were never presented. Moreover, our study is the first to show that this finding even held when trauma-related material was involved. Correlational analyses revealed that fantasy proneness, but not self-reported traumatic experiences and dissociative symptoms were related to false recall and false recognition.     

Predicting traumatic stress using emotional intelligence

The study investigated whether emotional intelligence (EI) can predict how individuals respond to traumatic experiences. A random sample of 414 participants (181 male, 233 female) were administered a measure of EI along with the Impact of Event Scale--revised [IES-R; Weiss, D. S. & Marmar, C. R. (1997). The Impact of Events Scale--revised. In J.P. Wilson & T.M. Keane (Eds.), Assessing psychological trauma and PTSD (pp. 399-411). New York: Guilford Press], and the monitoring and blunting questionnaire [MBQ, Anxiety Stress Coping 7 (1994) 53]. The results showed that participants with higher NEIS scores report fewer psychological symptoms relating to their traumatic experiences, that monitors are more likely to have higher NEIS scores than blunters. Traumatic events had a greater impact on females than males, and males had higher EI than females. The implications of these findings for using EI as a predictor for individuals who may experience traumatic stress are discussed.     

Amnesia,flashbacks, nightmares,and dissociation in aging concentration camp survivors

The current study examined to what extent war memories of Dutch survivors of Japanese/Indonesian concentration camps display characteristics that are often believed to be typical for traumatic memories. Twenty-nine survivors were interviewed about amnesia, flashbacks, nightmares and the sensory quality of their most upsetting war memories. In addition, they completed self-report scales measuring post-traumatic stress symptoms and dissociation. In contrast to prevailing notions, amnesia, flashbacks and nightmares were not typical for this sample. Neither were traumatic memories characterized by a particularly strong sensory loading. Post-traumatic stress symptoms were not related to dissociative experiences. At least for this group of aging survivors, it appears that the pathogenic potential of traumatic memories has more to do with their extremely aversive content than with a qualitatively different type of organization of these memories.     

Dental phobias and anxieties: evidence for conditioning processes in the acquisition and modulation of a learned fear

The present study investigated some of the factors which differentiate individuals with dental anxieties and phobias from those without such fears. In particular, two questions were addressed: (i) What differentiates subjects who have never been anxious about dental treatment from subjects who at some time have been anxious? and (ii) What factors lead to subjects changing their attitudes either from anxious to relaxed or from relaxed to anxious? The results suggest that the factors which influence the acquisition and modulation of dental anxieties are consistent with the associative and representational processes portrayed in contemporary models of human conditioning. Subjects who reported never having had anxieties about dental treatment were less likely to have had a painful dental treatment than subjects who did report an anxiety. Subjects who did report a painful dental experience but did not acquire anxiety reported a history of dental treatment favourable to the operation of latent inhibition. Subjects who reported that they were good at enduring pain were more likely to report a longer interval between their very first dental treatment and their first painful dental treatment. Under some conditions in which latent inhibition should have precluded the acquisition of a dental fear, an anxiety appeared to be acquired because a very painful experience had attenuated the latent inhibition process. Subjects whose dental anxiety did not remit reported significantly more painful and traumatic dental experiences than subjects whose anxiety did remit.     

Optimism, coping, and health: assessment and implications of generalized outcome expectancies

This article describes a scale measuring dispositional optimism, defined in terms of generalized outcome expectancies. Two preliminary studies assessed the scale's psychometric properties and its relationships with several other instruments. The scale was then used in a longitudinal study of symptom reporting among a group of undergraduates. Specifically, respondents were asked to complete three questionnaires 4 weeks before the end of a semester. Included in the questionnaire battery was the measure of optimism, a measure of private self-consciousness, and a 39-item physical symptom checklist. Subjects completed the same set of questionnaires again on the last day of class. Consistent with predictions, subjects who initially reported being highly optimistic were subsequently less likely to report being bothered by symptoms (even after correcting for initial symptom-report levels) than were subjects who initially reported being less optimistic. This effect tended to be stronger among persons high in private self-consciousness than among those lower in private self-consciousness. Discussion centers on other health related applications of the optimism scale, and the relationships between our theoretical orientation and several related theories.     

Dissociative experiences, psychopathology and adjustment, and child and adolescent maltreatment in female college students.

Thirty-three female college students who scored in the upper 15% on the Dissociative Experiences Scale (DES) were compared with 33 female students who scored below the mean on the DES on measures of psychopathology (Symptom Checklist-90), college adjustment (Student Adaptation to College Questionnaire), and child and adolescent maltreatment. Compared with controls, high-DES subjects reported more psychopathology, poorer college adjustment, and a greater extent of psychological, physical, and sexual maltreatment. On the basis of the Dissociative Disorders Interview Schedule, 2 high-DES subjects but none of the control subjects met criteria for a dissociative disorder (i.e., multiple personality and psychogenic amnesia). Despite the sensitivity of the DES, 8 subjects who scored in the upper 2% of the population on the DES failed to meet criteria for a dissociative disorder.     

Relationship of purported measures of pathological and nonpathological dissociation to self-reported psychological distress and fantasy immersion

In order to investigate both the psychometric structure of the Dissociative Experiences Survey (DES) and the discriminant validity of the DES-Taxon (Waller, Putnam, & Carlson, 1996) as a specific marker of pathological dissociation, 376 non-clinical community based respondents completed the DES and a battery of psychopathology and imaginative involvement self-report measures. The DES was scored for both the Taxon and the DES-Absorption subscale. A DES subscale purported to tap normative dissociative processes. The two DES subscales demonstrated substantial overlap, both with each other (r = .80) and with the self-report measures with both DES scales comparably associated with high levels of psychological distress. Both DES subscales were also associated with elevated levels of "normative" imaginative involvement (fantasy proneness, absorption, daydreaming immersion). We conclude that both DES scales are largely indistinguishable from each other in relation to other self-report measures of psychopathology and fantasy access.     

Physiologic Response,Perceptual Threshold,and Rorschach Test Anxiety Indices

This study examined the sensitivity and specificity of the Trauma Symptom Inventory (TSI, Briere, 1995), a self-report measure of psychological sequelae of potentially traumatic events, to malingering. An optimal cutting score for a validity scale—Atypical Responding (ATR)—designed to identify exaggeration or other unusual response sets was developed in an analogue sample of 155 college students and subsequently applied to TSI profiles from several samples of patients with various psychiatric disorders. Use of a cross-validated T-score cutoff of 61 and below on the ATR scale produced good sensitivity (81%) and specificity (92%) rates in the analogue sample. Participants in the analogue sample who reported a history of traumatic experiences were no more able to successfully malinger trauma, symptoms than were participants without such histories. Furthermore, false-positive rates in the clinical samples were generally low, suggesting that relatively few genuinely symptomatic individuals would be misclassified as malingering.