The Roles of Noradrenergic and Glucocorticoid Activation in the Development of Intrusive Memories

Intrusive memories are a common feature of many psychological disorders. Recent evidence has potentially extended cognitive models of intrusions by identifying the role of biological markers of arousal at the time of consolidation in subsequent memory for emotional events. This study investigated the role of arousal during consolidation in the development of intrusive memories. Seventy-eight university students (37 men and 41 women) viewed 20 negative and 20 neutral images. Half the participants then underwent a cold pressor test (High Stress), immersing their hand in ice water, while the remaining participants immersed their hand in warm water (Low Stress). Samples of salivary alpha-amylase (sAA) and cortisol were collected from participants at baseline and following the stressor challenge. Participants completed a delayed free recall test and intrusion questionnaires two days later. Participants in the High Stress condition reported more intrusions of negative images than participants in the Low Stress condition. An interaction variable in a linear regression of increased noradrenergic and cortisol values predicted intrusive memories of emotional stimuli for men but not women. These findings are consistent with recent evidence of the combined effects of noradrenaline and corticoid responses to stress on emotional memories, and also with increasing evidence of gender differences in how stress hormones influence formation of emotional memories. These findings point to possible mechanisms by which development of intrusions may be prevented after consolidation of traumatic experiences.     

Conflict Nightmares and Trauma in Aceh

In both the Acehnese and Indonesian languages, there is no single lexical term for “nightmare.” And yet findings from a large field research project in Aceh that examined post traumatic experience during Aceh’s nearly 30-year rebellion against the Indonesian state and current mental distress revealed a rich variety of dream narratives that connect directly and indirectly to respondents’ past traumatic experiences. The results reported below suggest that even in a society that has a very different cultural ideology about dreams, where “nightmares” as such are not considered dreams but rather the work of mischievous spirits called jin, they are still a significant part of the trauma process. We argue that it is productive to distinguish between terrifying and repetitive dreams that recreate the traumatic moment and the more ordinary varieties of dreams that Acehnese reported to their interviewers. Nightmares that refer back to conflict events do not appear as an elaborated feature of trauma as the condition is understood by people in Aceh, but when asked further about their dreams, respondents who reported symptoms suggestive of PTSD were more likely to report PTSD-like dreams, memory intrusions that repeat the political violence of the past.

In Search of the Trauma Memory: A Meta-Analysis of Functional Neuroimaging Studies of Symptom Provocation in Posttraumatic Stress Disorder (PTSD)

Notwithstanding some discrepancy between results from neuroimaging studies of symptom provocation in posttraumatic stress disorder (PTSD), there is broad agreement as to the neural circuit underlying this disorder. It is thought to be characterized by an exaggerated amygdalar and decreased medial prefrontal activation to which the elevated anxiety state and concomitant inadequate emotional regulation are attributed. However, the proposed circuit falls short of accounting for the main symptom, unique among anxiety disorders to PTSD, namely, reexperiencing the precipitating event in the form of recurrent, distressing images and recollections. Owing to the technical demands, neuroimaging studies are usually carried out with small sample sizes. A meta-analysis of their findings is more likely to cast light on the involved cortical areas. Coordinate-based meta-analyses employing ES-SDM (Effect Size Signed Differential Mapping) were carried out on 19 studies with 274 PTSD patients. Thirteen of the studies included 145 trauma-exposed control participants. Comparisons between reactions to trauma-related stimuli and a control condition and group comparison of reactions to the trauma-related stimuli were submitted to meta-analysis. Compared to controls and the neutral condition, PTSD patients showed significant activation of the mid-line retrosplenial cortex and precuneus in response to trauma-related stimuli. These midline areas have been implicated in self-referential processing and salient autobiographical memory. PTSD patients also evidenced hyperactivation of the pregenual/anterior cingulate gyrus and bilateral amygdala to trauma-relevant, compared to neutral, stimuli. Patients showed significantly less activation than controls in sensory association areas such as the bilateral temporal gyri and extrastriate area which may indicate that the patients’ attention was diverted from the presented stimuli by being focused on the elicited trauma memory. Being involved in associative learning and priming, the retrosplenial cortex may have an important function in relation to trauma memory, in particular, the intrusive reexperiencing of the traumatic event.     

Trauma, dreaming, and psychological distress among Kurdish children.

The authors examined (a) how traumatic events are associated with children's dream structure and content and (b) which dream characteristics might moderate the negative impact of traumatic events on mental health. Participants were 122 Kurdish children (9-17 years old, M = 13.02, SD = 1.66). Their dreams were collected during 1 week using a semistructured dream diary and scored according to the dream atmosphere, the role of the dreamer, bizarreness, narrative quality, fragmentation and resolution, and content such as themes of death, persecution and rejection, hostility, and anxiety. The results substantiated the hypothesis that children exposed to a high level of traumatic events would report dreams characterized by unpleasant atmosphere, fragmented flow, and low levels of bizarre narrative quality. Pleasant dreams containing complete narratives and happy endings moderated the negative impact of traumatic events on children's mental health. The authors argue that dreaming allows cognitive-emotional processing of traumatic events and may thus enhance child well-being in war conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Key steps in developing a cognitive vaccine against traumatic flashbacks: visuospatial Tetris versus verbal Pub Quiz

Background

Flashbacks (intrusive memories of a traumatic event) are the hallmark feature of Post Traumatic Stress Disorder, however preventative interventions are lacking. Tetris may offer a ‘cognitive vaccine’ [1] against flashback development after trauma exposure. We previously reported that playing the computer game Tetris soon after viewing traumatic material reduced flashbacks compared to no-task [1]. However, two criticisms need to be addressed for clinical translation: (1) Would all games have this effect via distraction/enjoyment, or might some games even be harmful? (2) Would effects be found if administered several hours post-trauma? Accordingly, we tested Tetris versus an alternative computer game – Pub Quiz – which we hypothesized not to be helpful (Experiments 1 and 2), and extended the intervention interval to 4 hours (Experiment 2).

Methodology/Principal Findings

The trauma film paradigm was used as an experimental analog for flashback development in healthy volunteers. In both experiments, participants viewed traumatic film footage of death and injury before completing one of the following: (1) no-task control condition (2) Tetris or (3) Pub Quiz. Flashbacks were monitored for 1 week. Experiment 1: 30 min after the traumatic film, playing Tetris led to a significant reduction in flashbacks compared to no-task control, whereas Pub Quiz led to a significant increase in flashbacks. Experiment 2: 4 hours post-film, playing Tetris led to a significant reduction in flashbacks compared to no-task control, whereas Pub Quiz did not.

Conclusions/Significance

First, computer games can have differential effects post-trauma, as predicted by a cognitive science formulation of trauma memory. In both Experiments, playing Tetris post-trauma film reduced flashbacks. Pub Quiz did not have this effect, even increasing flashbacks in Experiment 1. Thus not all computer games are beneficial or merely distracting post-trauma - some may be harmful. Second, the beneficial effects of Tetris are retained at 4 hours post-trauma. Clinically, this delivers a feasible time-window to administer a post-trauma “cognitive vaccine”.     

Relationship between Fear Conditionability and Aversive Memories: Evidence from a Novel Conditioned-Intrusion Paradigm

Intrusive memories – a hallmark symptom of posttraumatic stress disorder (PTSD) – are often triggered by stimuli possessing similarity with cues that predicted or accompanied the traumatic event. According to learning theories, intrusive memories can be seen as a conditioned response to trauma reminders. However, direct laboratory evidence for the link between fear conditionability and intrusive memories is missing. Furthermore, fear conditioning studies have predominantly relied on standardized aversive stimuli (e.g. electric stimulation) that bear little resemblance to typical traumatic events. To investigate the general relationship between fear conditionability and aversive memories, we tested 66 mentally healthy females in a novel conditioned-intrusion paradigm designed to model real-life traumatic experiences. The paradigm included a differential fear conditioning procedure with neutral sounds as conditioned stimuli and short violent film clips as unconditioned stimuli. Subsequent aversive memories were assessed through a memory triggering task (within 30 minutes, in the laboratory) and ambulatory assessment (involuntary aversive memories in the 2 days following the experiment). Skin conductance responses and subjective ratings demonstrated successful differential conditioning indicating that naturalistic aversive film stimuli can be used in a fear conditioning experiment. Furthermore, aversive memories were elicited in response to the conditioned stimuli during the memory triggering task and also occurred in the 2 days following the experiment. Importantly, participants who displayed higher conditionability showed more aversive memories during the memory triggering task and during ambulatory assessment. This suggests that fear conditioning constitutes an important source of persistent aversive memories. Implications for PTSD and its treatment are discussed.     

Decoding the Traumatic Memory among Women with PTSD: Implications for Neurocircuitry Models of PTSD and Real-Time fMRI Neurofeedback

Posttraumatic Stress Disorder (PTSD) is characterized by intrusive recall of the traumatic memory. While numerous studies have investigated the neural processing mechanisms engaged during trauma memory recall in PTSD, these analyses have only focused on group-level contrasts that reveal little about the predictive validity of the identified brain regions. By contrast, a multivariate pattern analysis (MVPA) approach towards identifying the neural mechanisms engaged during trauma memory recall would entail testing whether a multivariate set of brain regions is reliably predictive of (i.e., discriminates) whether an individual is engaging in trauma or non-trauma memory recall. Here, we use a MVPA approach to test 1) whether trauma memory vs neutral memory recall can be predicted reliably using a multivariate set of brain regions among women with PTSD related to assaultive violence exposure (N=16), 2) the methodological parameters (e.g., spatial smoothing, number of memory recall repetitions, etc.) that optimize classification accuracy and reproducibility of the feature weight spatial maps, and 3) the correspondence between brain regions that discriminate trauma memory recall and the brain regions predicted by neurocircuitry models of PTSD. Cross-validation classification accuracy was significantly above chance for all methodological permutations tested; mean accuracy across participants was 76% for the methodological parameters selected as optimal for both efficiency and accuracy. Classification accuracy was significantly better for a voxel-wise approach relative to voxels within restricted regions-of-interest (ROIs); classification accuracy did not differ when using PTSD-related ROIs compared to randomly generated ROIs. ROI-based analyses suggested the reliable involvement of the left hippocampus in discriminating memory recall across participants and that the contribution of the left amygdala to the decision function was dependent upon PTSD symptom severity. These results have methodological implications for real-time fMRI neurofeedback of the trauma memory in PTSD and conceptual implications for neurocircuitry models of PTSD that attempt to explain core neural processing mechanisms mediating PTSD.     

How Visual Figures Speak: Narrative Inventions of "The Pastoralist" in East Africa

Through their media images, pastoralists have become "icons" of African traditionalism and unwitting symbols of resistance to the modernist values of development and conservation. Their pictorial fame bears political costs. Popular visual images convey tacit narrative presuppositions that shape public (mis)understanding of pastoral communities, as tacitly pejorative images of pastoralists--most notably of Maasai--proliferate in film, tourist brochures, and advertising, at a time when pastoral communities are faced with political marginalization and dispossession. This article examines the narratives implicit in ethnographic images of pastoralists, images that support the "fulfillment" of pastoral "characters" through policies detrimental to their future.     

The presence of the past: youth,memory making and the politics of self-determination in southeastern Nigeria

This article focuses on recent reconstructions of Igbo ‘memory’ by the Movement for the Actualization of the Sovereign state of Biafra (MASSOB). MASSOB is a second-generation Igbo separatist movement that draws on a collection of ‘memory repertoires’ to agitate for the self-determination and exit of the Igbo ethnic group from the Nigerian state into an alternative political and administrative arrangement known as the Republic of Biafra. The core issues relate to dual narratives generated by the Nigerian–Biafran War. While the state shapes the official history, memories and narratives of the war to suit its own vision, interests and politics, MASSOB contests these official views as the sole legitimate framework for remembering and interpreting the war, but still connects to the war as a war of Igbo national liberation. These contestations provide the context for the enactment of memory claims and counterclaims, and their association with political violence in contemporary Nigeria.     

Falling Out of Time: Enhanced Memory for Scenes Presented at Behaviorally Irrelevant Points in Time in Posttraumatic Stress Disorder (PTSD)

Spontaneous encoding of the visual environment depends on the behavioral relevance of the task performed simultaneously. If participants identify target letters or auditory tones while viewing a series of briefly presented natural and urban scenes, they demonstrate effective scene recognition only when a target, but not a behaviorally irrelevant distractor, appears together with the scene. Here, we show that individuals with posttraumatic stress disorder (PTSD), who witnessed the red sludge disaster in Hungary, show the opposite pattern of performance: enhanced recognition of scenes presented together with distractors and deficient recognition of scenes presented with targets. The recognition of trauma-related and neutral scenes was not different in individuals with PTSD. We found a positive correlation between memory for scenes presented with auditory distractors and re-experiencing symptoms (memory intrusions and flashbacks). These results suggest that abnormal encoding of visual scenes at behaviorally irrelevant events might be associated with intrusive experiences by disrupting the flow of time.     

Narrative Length and Speech Rate in Battered Women

Narrative length and speech rate of traumatic recollections have been previously associated with different emotions and adjustment trajectories after trauma. However, the evidence is limited and the results are mixed. The present study aimed to evaluate length (i.e., word count) and speech rate (i.e., words per minute) in narratives of events with different valence (i.e., neutral, positive, and negative/traumatic) by 50 battered women (trauma group) and 50 non-traumatized women (controls). The results showed that traumatic narratives by the trauma group were longer than those by the control group. Moreover, they were inversely related to time since the event and anxiety during disclosure, whereas the speech rate was also inversely associated with anxiety, as well as with peritraumatic dissociation and avoidance. The shorter narratives for positive events and a decelerated speech pattern for traumatic experiences predicted psychological symptoms. Additionally, the individual’s emotional state predicted narrative aspects, with bidirectional effects. Our findings showed that linguistic characteristics of traumatic narratives (but also of narratives of positive events) revealed information about how the victims elaborated autobiographical memories and coped with the trauma.     

PRKCA Polymorphism Changes the Neural Basis of Episodic Remembering in Healthy Individuals

Everyday functioning relies on episodic memory, the conscious retrieval of past experiences, but this crucial cognitive ability declines severely with aging and disease. Vulnerability to memory decline varies across individuals however, producing differences in the time course and severity of memory problems that complicate attempts at diagnosis and treatment. Here we identify a key source of variability, by examining gene dependent changes in the neural basis of episodic remembering in healthy adults, targeting seven polymorphisms previously linked to memory. Scalp recorded Event-Related Potentials (ERPs) were measured while participants remembered words, using an item recognition task that requires discrimination between studied and unstudied stimuli. Significant differences were found as a consequence of a Single Nucleotide Polymorphism (SNP) in just one of the tested genes, PRKCA (rs8074995). Participants with the common G/G variant exhibited left parietal old/new effects, which are typically seen in word recognition studies, reflecting recollection-based remembering. During the same stage of memory retrieval participants carrying a rarer A variant exhibited an atypical pattern of brain activity, a topographically dissociable frontally-distributed old/new effect, even though behavioural performance did not differ between groups. Results replicated in a second independent sample of participants. These findings demonstrate that the PRKCA genotype is important in determining how episodic memories are retrieved, opening a new route towards understanding individual differences in memory.     

From Serbia with Hate: A Case Study in Globalization, Trauma, and Language

This article analyzes a set of five postcards, purchased from a street stand in Belgrade, the capital of Yugoslavia, shortly after the NATO bombing of the country took place in the spring of 1999. While the postcards obviously serve as protests against the bombing, as well as testimonies of the nation-wide trauma caused by it, they also reveal a careful negotiation between representations of trauma — keeping it displaced enough to avoid vicarious traumatization for individual survivors, but focused enough to translate it into a part of the national Serb identity and relying on the symbolism available in historical public narratives. However, since all the postcards analyzed here use English language in one form or another, they can also be read as peculiar interpretations of globalization on a local level. The article is an examination of the function of English, both in the negotiation of private/public trauma as described above, and its role in the complex reconfiguration of the phenomenon of globalization as embedded with local meaning given the context of the narrative within the Serbian popular culture. While these pop culture artifacts offer an assurance to the Serb national spirit, they also express a multifaceted national take on globalization visible in the use of English as the language of the Western ‘enemy’. Overall,the postcards can be read as a curious traumatic figuration of postmodernism which seems to be battling modernism in Belgrade's streets, while the Serb nationalism faces off with the global world in the realm of the imaginary.     

Remembering Collective Violence: Broadening the Notion of Traumatic Memory in Post-Conflict Rehabilitation

In the aftermath of war and armed conflict, individuals and communities face the challenge of dealing with recollections of violence and atrocity. This article aims to contribute to a better understanding of processes of remembering and forgetting histories of violence in post-conflict communities and to reflect on related implications for trauma rehabilitation in post-conflict settings. Starting from the observation that memory operates at the core of PTSD symptomatology, we more closely explore how this notion of traumatic memory is conceptualized within PTSD-centered research and interventions. Subsequently, we aim to broaden this understanding of traumatic memory and post-trauma care by connecting to findings from social memory studies and transcultural trauma research. Drawing on an analysis of scholarly literature, this analysis develops into a perspective on memory that moves beyond a symptomatic framing toward an understanding of memory that emphasizes its relational, political, moral, and cultural nature. Post-conflict memory is presented as inextricably embedded in communal relations, involving ongoing trade-offs between individual and collective responses to trauma and a complex negotiation of speech and silence. In a concluding discussion, we develop implications of this broadened understanding for post-conflict trauma-focused rehabilitation.     

Active Memory

Collective memory is a phenomenon that receives a different interpretation depending on the discipline within which it is examined. In my research, I will employ ideas and concepts developed within the framework of a sociocultural approach (Wertsch, 2002; Cole, 1996). In particular, I will proceed from the definition of collective memory developed by James Wertsch (2002), who treats collective memory as textually mediated memory, conditioned by various—mainly historical—narratives. Historical narratives (annals, chronicles, history textbooks, etc.) are considered to be cultural instruments promoting collective remembrance. A category I borrow from Wertsch's work (2002) is the concept of the "schematic narrative template," which I will apply as analytic tool in my investigation of the phenomenon of collective memory phenomenon.     

You look familiar: how Malaysian Chinese recognize faces

East Asian and white Western observers employ different eye movement strategies for a variety of visual processing tasks, including face processing. Recent eye tracking studies on face recognition found that East Asians tend to integrate information holistically by focusing on the nose while white Westerners perceive faces featurally by moving between the eyes and mouth. The current study examines the eye movement strategy that Malaysian Chinese participants employ when recognizing East Asian, white Western, and African faces. Rather than adopting the Eastern or Western fixation pattern, Malaysian Chinese participants use a mixed strategy by focusing on the eyes and nose more than the mouth. The combination of Eastern and Western strategies proved advantageous in participants' ability to recognize East Asian and white Western faces, suggesting that individuals learn to use fixation patterns that are optimized for recognizing the faces with which they are more familiar.     

Whiteness and loss in outer East London: tracing the collective memories of diaspora space

Abstract

This paper explores collective memory in Newham, East London. It addresses how remembering East London as the home of whiteness and traditional forms of community entails powerful forms of forgetting. Newham's formation through migration – its ‘great time’ – has ensured that myths of indigeneity and whiteness have never stood still. Through engaging with young people's and youth workers' memory practices, the paper explores how phantasms of whiteness and class loss are traced over, and how this tracing reveals ambivalence and porosity, at the same time as it highlights the continued allure of race. It explores how whiteness and class loss are appropriated across ethnic boundaries and how they are mobilized to produce new forms of racial hierarchy in a ‘super-diverse’ place.