Perspectives on Memory for Trauma and Cognitive Processes Associated with Dissociative Tendencies

Summary

Cognitive science approaches can inform research in traumatic stress studies by articulating separate scientific issues that may be relevant to understanding alterations in memory and awareness for trauma. This article will first address general issues about disrupted memory and “knowledge isolation” for trauma, as well as introduce specific aspects of “betrayal trauma theory” (Freyd 1994, 1996) that inform our understanding of memory impairment. According to betrayal trauma theory, a potent motivation for knowledge isolation (including amnesia, dissociation, and unawareness) in the face of trauma is to preserve apparently necessary human relationships in which betrayal occurs. Results from three recent laboratory investigations of cognitive processes associated with dissociative tendencies are summarized. These laboratory investigations suggest that the attentional capacities of high dissocators are impaired under conditions of selective attention, but not divided attention. Furthermore, in our laboratory tasks high dissocators have impaired memory for emotionally charged words associated with sexual assault and abuse (e.g., “incest”) but not neutral words, as compared with low dissociators. The findings suggest that high dissociators use divided attention and multi-tasking as a way to control the flow of information. Such a view is consistent with betrayal trauma theory. Though in its infancy, this research draws on cognitive science and observations of traumatic response and offers much promise.     

Dissociative tendencies and memory performance on directed-forgetting tasks

The current article presents two studies that aimed to replicate DePrince and Freyd's (2001, 2004) studies demonstrating that high and low dissociators differentially recall neutral and trauma words under conditions of varying cognitive load. We did not find this effect. This lack of replication was apparent for both free recall and word recognition memory and in both studies. In effect, we found little evidence to support betrayal trauma theory, yet observed increased memory fallibility, as demonstrated by lower general recall and (in one study) commission errors, in high dissociators.     

创伤性分离个体注意加工的Stroop效应

研究采用Stroop色词命名任务。实验主要考察创伤性分离个体注意的加工模式。实验中,高分离个体在标准Stroop任务条件,明显受到Stroop效应的干扰,对创伤性词汇反应时间减慢。实验结果表明,创伤性分离个体的集中注意能力遭到破坏,实验符合创伤的回避加工理论,创伤性分离个体运用分离无意识忽略注意伤害性的刺激,如果无法忽略,则会有意识的回避加工。     

Forgetting of trauma cues in adults reporting continuous or recovered memories of childhood sexual abuse

According to betrayal trauma theory, adult survivors of childhood sexual abuse (CSA) who were molested by their caretakers (e.g., a father) are especially likely to dissociate ("repress") their memories of abuse. Testing college students, some reporting CSA, DePrince and Freyd (2004) found that those scoring high on a dissociation questionnaire exhibited memory deficits for trauma words when they viewed these words under divided-attention conditions. Replicating DePrince and Freyd's procedure, we tested for memory deficits for trauma words relative to neutral words in adults reporting either continuous or recovered memories of CSA versus adults denying a history of CSA. A memory deficit for trauma words under divided attention was expected in the recovered-memory group. Results were inconsistent with this prediction, as all three groups exhibited better recall of trauma words than neutral words, irrespective of encoding conditions.     

Weak evidence for increased motivated forgetting of trauma-related words in dissociated or traumatised individuals in a directed forgetting experiment

Motivated forgetting is the idea that people can block out, or forget, upsetting or traumatic memories, because there is a motivation to do so. Some researchers have cited directed forgetting studies using trauma-related words as evidence for the theory of motivated forgetting of trauma. In the current article subjects used the list method directed forgetting paradigm with both trauma-related words and positive words. After one list of words was presented subjects were directed to forget the words previously learned, and they then received another list of words. Each list was a mix of positive and trauma-related words, and the lists were counterbalanced. Later, subjects recalled as many of the words as they could, including the ones they were told to forget. Based on the theory that motivated forgetting would lead to recall deficits of trauma-related material, we created eight hypotheses. High dissociators, trauma-exposed, sexual trauma-exposed, and high dissociators with trauma-exposure participants were hypothesised to show enhanced forgetting of trauma words. Results indicated only one of eight hypotheses was supported: those higher on dissociation and trauma recalled fewer trauma words in the to-be-forgotten condition, compared to those low on dissociation and trauma. These results provide weak support for differential motivated forgetting.     

Insult,then Injury: Interpersonal and Institutional Betrayal Linked to Health and Dissociation

Psychological trauma, particularly trauma involving betrayal, has been linked to health problems. Betrayal trauma is also characterized by dissociation and difficulty remembering as victims face conflicting demands presented by a harmful but important relationship. Institutional betrayal is related to, but distinct from, interpersonal betrayal and in need of research on its unique effects. The current study has two related goals. First, the association between institutional betrayal and health problems is examined. Second, the previously documented association between institutional betrayal and dissociative symptoms is re-examined, while controlling for betrayal trauma. This study utilizes a sample of 302 college students (70% female, 63% Caucasian) who reported their trauma history (Brief Betrayal Trauma Survey), institutional betrayal history (Institutional Betrayal Questionnaire), distress related to health problems (Patient Health Questionnaire), and dissociative symptoms (Wessex Dissociation Scale). We found that institutional betrayal is uniquely associated with both health problems and dissociative symptoms even when controlling for betrayal trauma exposure. Findings add to the understanding of how institutional betrayal is uniquely associated to trauma-related physical and mental health outcomes. Small effect sizes, likely due to low base rates of health problems and dissociative symptoms in college students, and problems generalizing these results to clinical samples are discussed.     

媒体多任务的效用：听觉信息干扰和视听信息整合的实验证据

采用心理旋转范式和词汇判断范式,探讨媒体多任务经验不同者在听觉信息干扰和视听信息整合情境下对图形一致性和真假词的判断表现。结果发现：（1）以判断图形一致性为实验任务,在无声和低音干扰条件下,低经验组的正确率均显著高于高经验组,两组的反应时差异均不显著;在高音干扰条件下,高经验组的反应时显著短于低经验组,正确率则没有显著差异。（2）以真假词判断为实验任务,对真词进行判断,在三种听觉条件下,高经验组在语音匹配条件下的反应时最短,与低经验组无显著差异,但正确率显著高于低经验组,与另两种听觉条件没有显著差异;低经验组在语音匹配条件下的反应时显著长于另两种听觉条件,正确率则显著高于无声条件,与不匹配条件差异不显著。对假词的判断,低经验组在三种听觉条件下的反应时均显著短于高经验组,正确率与高经验组均无显著差异。研究表明,媒体多任务经验丰富者相比经验缺乏者受到任务无关的纯短高音干扰的影响要小,在需要视听通道语义整合的加工中具有一定的优势。     

Relationships between trait impulsivity and cognitive control: the effect of attention switching on response inhibition and conflict resolution

This study examined the relationship between trait impulsivity and cognitive control, as measured by the Barratt Impulsiveness Scale (BIS) and a focused attention dichotic listening to words task, respectively. In the task, attention was manipulated in two attention conditions differing in their cognitive control demands: one in which attention was directed to one ear at a time for a whole block of trials (blocked condition) and another in which attention was switched pseudo-randomly between the two ears from trial to trial (mixed condition). Results showed that high impulsivity participants exhibited more false alarm and intrusion errors as well as a lesser ability to distinguish between stimuli in the mixed condition, as compared to low impulsivity participants. In the blocked condition, the performance levels of the two groups were comparable with respect to these measures. In addition, total BIS scores were correlated with intrusions and laterality index in the mixed but not the blocked condition. The findings suggest that high impulsivity individuals may be less prone to attentional difficulties when cognitive load is relatively low. In contrast, when attention switching is involved, high impulsivity is associated with greater difficulty in inhibiting responses and resolving cognitive conflict than is low impulsivity, as reflected in error-prone information processing. The conclusion is that trait impulsivity in a non-clinical population is manifested more strongly when attention switching is required than during maintained attention. This may have important implications for the conceptualization and treatment of impulsivity in both non-clinical and clinical populations.     

The effects of cognitive load on attention control in subclinical anxiety and generalised anxiety disorder

Poor regulation of emotions may involve impaired attention control. In the current paper, we report the results of two studies examining the interaction of anxiety, attention control and cognitive load. In Study I, using a performance-based task to assess attention control, we examined whether anxiety is associated with impaired attention control, and whether these effects are influenced by working memory load. In Study II, we examined these effects in patients with a diagnosis of generalised anxiety disorder (GAD) compared to non-anxious control (NAC) participants. Results of Study I showed that high anxiety was associated with increased attention control, that is decreased interference from distractors, but only under high cognitive load. These results were replicated in Study II such that individuals with GAD showed increased attention control relative to NACs, but only under high cognitive load. These results help clarify previous predictions regarding the effect of anxiety on attention control.     

Self‐oriented perfectionism and its relationship to selective attention: An experimental examination using social cognitive paradigm1

The cognitive biases associated with perfectionism include a selective attention to failure and the discounting of success. The present study experimentally focused on the relation between self‐oriented perfectionism (SOP) and selective attention using the social cognitive paradigm. Forty undergraduate students who were identified as either high or low in SOP were asked to perform modified versions of the Stroop task. The results suggest that participants with high SOP did not take longer to respond to failure words than to neutral words, but their reaction time to failure words was longer than that of participants with low SOP. These findings provided the basis for cognitive behavioral biases for perfectionism.     

认知负载对基于动机的情绪刺激加工的影响

结合数数任务和情绪flanker任务,探究不同认知负载条件下,高低趋近动机对情绪刺激加工的影响。结果发现：高负载组中,高趋近动机条件下,对积极目标刺激的反应显著快于消极目标刺激;低趋近动机条件下,对消极目标刺激的反应显著快于积极目标刺激。且高负载组中,各条件下的反应大多都显著慢于低负载组。低负载组中没有发现各条件之间的差异。结果表明,高负载条件下,高趋近动机促进了积极情绪刺激的加工,低趋近动机促进了消极情绪刺激的加工,高负载在一定程度上阻碍了情绪刺激的加工。     

认知负载对基于动机的情绪刺激加工的影响

结合数数任务和情绪flanker任务,探究不同认知负载条件下,高低趋近动机对情绪刺激加工的影响。结果发现：高负载组中,高趋近动机条件下,对积极目标刺激的反应显著快于消极目标刺激;低趋近动机条件下,对消极目标刺激的反应显著快于积极目标刺激。且高负载组中,各条件下的反应大多都显著慢于低负载组。低负载组中没有发现各条件之间的差异。结果表明,高负载条件下,高趋近动机促进了积极情绪刺激的加工,低趋近动机促进了消极情绪刺激的加工,高负载在一定程度上阻碍了情绪刺激的加工。     

Decision-making,cognitive functions,impulsivity, and media multitasking expectancies in high versus low media multitaskers

In several studies, individuals who reported to frequently multitask with different media displayed reduced cognitive performance, for example in fluid intelligence and executive functioning. These cognitive functions are relevant for making advantageous decisions under both objective risk (requiring reflection and strategical planning) and ambiguous risk (requiring learning from feedback). Thus, compared to low media multitaskers (LMMs), high media multitaskers (HMMs) may perform worse in both types of decision situations. The current study investigated HMMs and LMMs in a laboratory setting with the Game of Dice Task (GDT; objective risk), the Iowa Gambling Task (IGT; ambiguous risk), various tests quantifying cognitive functions (logical reasoning, working memory, information processing, general executive functions), and self-report measures of impulsivity, media multitasking expectancies, and problematic Internet use. From 182 participants, 25 HMMs and 19 LMMs were identified using the Media Multitasking Index. Results show that HMMs compared to LMMs performed weaker on the IGT but not on the GDT. Furthermore, HMMs had slightly decreased performance in tests of logical reasoning and working memory capacity. HMMs tended to increased information processing speed but this difference was not significant. Furthermore, HMMs have more positive expectancies regarding media multitasking and reported higher tendencies toward problematic Internet use. HMMs and LMMs did not differ significantly with respect to impulsivity and executive functions. The results give a first hint that HMMs may have difficulties in decision-making under ambiguous but not under objective risk. HMMs may be more prone to errors in tasks that require feedback processing. However, HMMs appear not to be impaired in aspects of long-term strategic decision-making.

     

听障儿童认知抑制控制的脑电特点

通过认知抑制控制的Stroop范式运用事件相关电位考察听障儿童和对照组儿童在认知抑制控制方面的行为特点以及脑内时程特点。行为结果显示：（1）两类被试在一致条件下认知抑制控制的正确率显著高于不一致条件,反应时显著快于不一致条件,表现出冲突效应;（2）组间结果显示,听障儿童的认知抑制控制正确率显著低于对照组儿童,反应时上差异不显著。脑电结果显示：（1）不一致条件在N450上的负激活显著高于一致条件,听障儿童比对照组儿童诱发了更负的N450波幅;（2）不一致条件在SP上的正激活显著高于一致条件,两类被试在SP上差异不显著。结果提示听障儿童在认知抑制控制过程中的冲突监测功能存在障碍,这是由于冲突监测过程中注意分配能力受损所致。     

高低创造性思维水平者定向遗忘效应的差异研究

采用单字法定向遗忘范式,考察远距离联想任务得分高低者在中性和负性词语定向遗忘效应上的差异,来探讨创造性思维水平高低与主动抑制的关系。实验采用2(高/低创造性思维水平)×2(中性/负性词汇)×2(记住/忘记指令)×2(2s/5s时间间隔)混合设计,发现高低创造力组,在材料不同呈现时间下,对不同情绪材料的定向遗忘效应分别不同。低创者在2s和5s以及高创者在5s时间间隔时,均对中性词语表现出定向遗忘效应,而对负性词汇没有表现出明显的定性遗忘效应。高创者在2s时间间隔下,对中性和负性词语均表现出定向遗忘效应。结果表明较短时间内高创者对负性情绪的主动抑制能力优于低创者。     

Hydrocortisone infusion exerts dose- and sex-dependent effects on attention to emotional stimuli

Glucocorticoid administration has been shown to exert complex effects on cognitive and emotional processing. In the current study we investigated the effects of glucocorticoid administration on attention towards emotional words, using an Affective Go/No-go task on which healthy humans have shown an attentional bias towards positive as compared to negative words. Healthy volunteers received placebo and either low-dose (0.15 mg/kg) or high-dose (0.45 mg/kg) hydrocortisone intravenously during two separate visits in a double-blind, randomized design. Seventy-five minutes post-infusion, the subjects performed tests of attention (Rapid Visual Information Processing [RVIP]), spatial working memory (Spatial Span) and emotional processing (Affective Go/No-go task [AGNG]). On the attention task, performance was impaired under both hydrocortisone doses relative to placebo, though the effect on error rate was not significant after controlling for age; Spatial Span performance was unaffected by hydrocortisone administration. On the AGNG task, relative to the placebo condition the low-dose hydrocortisone infusion decreased response time to emotional words while high-dose hydrocortisone increased response time. In the females specifically, both high and low dose hydrocortisone administration attenuated the normal attentional bias toward positively valenced words. These data suggest that, in healthy women, the modulation of attention by the emotional salience of stimuli is influenced by glucocorticoid hormone concentrations.     

Type A behaviour pattern and attentional bias in relation to anger/hostility, achievement, and failure

Type A subjects are characterised by dysfunctional cognitions related to themes of competitiveness, achievement, and hostility. The present experiment investigated attentional biases for words relevant to the content of these dysfunctional schemata in Type A individuals. After completing the MMPI-2 Type A Scale, subjects completed two alternative versions of a visual probe detection task (administered 4–12 days apart) which contained achievement, failure, and anger/hostility/aggression related words. Prior to testing at time 1, subjects were told that the purpose of the procedure was to collect normative data only. Prior to testing at time 2, subjects were told that performance on the test was known to be closely related to IQ and that they could compare their performance with that of other subjects following completion of the task. Type A subjects directed attention towards anger/hostility/aggression words under low performance motivation conditions but away from such words under high performance motivation conditions. Type A subjects also showed less selective attention to failure words than Type B subjects, and no group differences were detected for achievement related words. The results are discussed with reference to models of dysfunctional cognitive processing, and the role of anger/hostility, in particular, in Type A personality.     

Dissociation and memory suppression: A comparison of high and low dissociative individuals’ performance on the Think–No Think task

The present study examined whether high and low dissociative individuals differ in their ability to keep target stimuli out of their awareness (suppression) and how this relates to their memory of those targets during a later cued recall task. The prediction was that high dissociators display a general inability to focus attention and that their distractibility undermines successful suppression, thereby enhancing memory for suppressed items. College students with high (n = 35) and low (n = 33) scores on the Dissociative Experiences Scale participated in a Dutch version of Anderson and Green’s (2001) Think–No Think (TNT) task. Overall, a significant suppression effect emerged. However, no differences between high and low dissociators were observed. Thus, the present results do not confirm that dissociation is linked to heightened distractibility.     

Betrayal Trauma,Health Care Relationships,and Health in Patients with a Chronic Neurovascular Condition

Individuals who have been exposed to trauma are at a greater risk of developing a chronic physical health condition and use health services more frequently than individuals who have not experienced trauma. The mechanism by which trauma affects health is not fully understood, but relationships with health care providers could be important in understanding this association. The purpose of this study was to explore the relationships among betrayal trauma, health care relationships, and physical and mental health in a chronic medical population. Participants (N = 272) diagnosed with a chronic neurovascular condition (cavernous malformation) completed an online survey. Questionnaires assessed self-rated health, instances of betrayal trauma, posttraumatic stress disorder (PTSD) and depression symptoms, income, and other demographic factors, and health care relationships. Level of income and the experience of betrayal trauma predicted mental health symptoms (depression, PTSD, or both) and also predicted health care relationships. After controlling for income and previous trauma, mental health symptoms significantly predicted health care relationships. Finally, mental health symptoms, health care relationships, and income predicted self-rated health, although the associations were not straightforward. These results suggest complex interrelations among trauma, mental health, income, health care relationships, and physical health, and a model is proposed for explaining these associations.     

Memory for emotionally provocative words in alexithymia: A role for stimulus relevance

Alexithymia is associated with emotion processing deficits, particularly for negative emotional information. However, also common are a high prevalence of somatic symptoms and the perception of somatic sensations as distressing. Although little research has yet been conducted on memory in alexithymia, we hypothesized a paradoxical effect of alexithymia on memory. Specifically, recall of negative emotional words was expected to be reduced in alexithymia, while memory for illness words was expected to be enhanced in alexithymia.Eighty-five high or low alexithymia participants viewed and rated arousing illness-related (“pain”), emotionally positive (“thrill”), negative (“hatred”), and neutral words (“horse”). Recall was assessed 45 min later.High alexithymia participants recalled significantly fewer negative emotion words but also more illness-related words than low alexithymia participants. The results suggest that personal relevance can shape cognitive processing of stimuli, even to enhance retention of a subclass of stimuli whose retention is generally impaired in alexithymia.