Rapid emotional processing in relation to trauma-related symptoms as revealed by magnetic source imaging

Hypervigilance or shutdown? Electrophysiological processing of trauma-unrelated aversive stimuli after traumatic life events

Post-Traumatic Stress Disorder (PTSD) research indicates that hyper-reactivity to trauma-related stimuli reflects reduced prefrontal cortex (PFC) modulation of amygdala reactivity. However, other studies indicate a dissociative "shutdown" reaction to overwhelming aversive stimuli, possibly reflecting PFC over-modulation. To explore this, we used an Event-Related Potential (ERP) oddball paradigm to study P3 responses in the presence of the following: 1. Trauma-unrelated morbid distractors (e.g., "injured bear") related to the Rorschach inkblot test, and 2. Negative distractors (e.g., "significant failure"), among participants with high post-traumatic stress symptoms (PTS; n = 20), low PTS (n = 17), and controls (n = 15). Distractors were presented at 20% frequency amongst the more frequent (60%) neutral standard stimuli (e.g., "desk lamp") and the equally frequent (20%) neutral trauma-unrelated target stimulus ("golden fish"). P3 amplitudes were high in the presence of morbid distractors and low in the presence of negative distractors only amongst the control group. Possible mechanisms underlying the lack of P3 amplitude modulation after trauma are discussed.

Refugee Women with a History of Trauma: Gender Vulnerability in Relation to Post-Traumatic Stress Disorder

Refugees represent a population whose living conditions have a strong impact on their mental health. High rates of post-traumatic stress disorder (PTSD), more than other mental disorders, have been found in this group, with women having the highest incidence. The objective of the present systematic review was to identify and examine studies from the last fifteen years on the relationship between the impact of traumatic experiences and PTSD psychopathology in refugee women. Twelve studies were included, from which the overall results approved this relation. In addition, six of these studies show that exposure to sexual trauma in refugee women is associated with the high odds of being at risk for PTSD. These findings suggest that gender-related traumatic experiences can explain the high rate of PTSD in refugee women and highlight the unmet need for psychosocial health care in this population.

Encoding Pleasant and Unpleasant Expression of the Architectural Window Shapes: An ERP Study

The evaluation of building facades is one of the most important elements in built environments for helping architects and professionals to develop future designs. The form or shape of windows in building facades has direct impacts on perceivers’ affective state and emotions. To understand the impacts of geometric windows on the subject’s feedback and cortical activity, psychophysics experiments and electroencephalogram (EEG) recordings were measured from the participants. Our behavioral results show a distinguished categorization of the window shapes as pleasant and unpleasant stimuli. The rectangular, square, circular and semi-circular arch were determined as the pleasant window shapes, while the triangular and triangular arch window shapes were distinguished as unpleasant. Furthermore, event-related potential (ERP) components (N1, P2 and P3) were investigated to determine the influence of window shapes on the local brain activity. To measure reliable cortical responses, a Butterworth notch filter (50 Hz), band pass filter (0.1–60 Hz) and ADJUST filter were employed to remove the artifacts. The electrophysiological results show increased activity for the unpleasant in comparison to the pleasant windows (p < 0.05, Rank-Sum test) in both frontal (for P2 component) and posterio-occipital (ERP amplitudes; the N1 through to the P3 peak) channels. The ERP amplitudes of the right hemisphere were significantly larger than in the left hemisphere, not only in response to the unpleasant (p < 0.001) but also to the pleasant window stimuli (p < 0.001, Signed-Rank test). However, the unpleasant stimuli evoked significantly larger ERP amplitude than the pleasant stimuli. Moreover, the significant ERP_P2 amplitude was more distinguished for unpleasant (p = 0.01, Signed-Rank test) than pleasant windows (p = 0.01, Rank-Sum test) between frontal and central cortical lobes. Overall, our behavioral and electrophysiological studies demonstrate a distinguished categorization of pleasant and unpleasant window shapes and more significant ERP modulations in the right than left hemisphere for unpleasant windows compared to pleasant ones.

Rapid brain responses to affective pictures indicate dimensions of trauma-related psychopathology in adolescents

A variety of mental disorders are related to deviant brain activity, but these neural alterations do not validate psychiatric diagnostic categories. High symptom overlap and variable symptom patterns encourage a dimensional approach. Following the logic of the Research Domain Criteria (RDoC), we investigated trauma survivors for symptom clusters that might be associated with characteristics of ERPs, in particular with the early posterior negativity (EPN) elicited during affective picture processing. In rapid serial visual presentation, 90 adolescents (40 male/50 female, age M = 15.0 ± 2.5 years) who had been exposed to varying amounts of traumatic stress passively viewed a stream of high‐arousing positive and low‐arousing neutral pictures taken from the International Affective Picture System (IAPS). Using standardized interviews, symptoms of trauma‐related mental disorders were assessed (including those for PTSD, depression, borderline personality disorder, and behavioral problems). A principal component analysis was performed to derive potential dimensions of psychopathology. Multiple regression analysis confirmed a factor comprising problems concentrating, sleeping difficulties, and mistrust as a predictor of a larger EPN difference between high‐arousing positive and low‐arousing neutral IAPS pictures (β = 0.19, p < 0.05). Sex predicted the magnitude of the EPN (β = 0.45, p < 0.001). Male adolescents displayed a stronger EPN suppression than female adolescents. The result suggests that problems concentrating, sleeping difficulties, and mistrust seem to be trans‐diagnostic elements related to diminished early emotional discrimination represented by the EPN. Furthermore, our findings indicate that the EPN in response to emotional processing is modulated by sex.

Based on the RDoC heuristic, symptom clusters that may be associated with the early posterior negativity (EPN) elicited during affective picture processing were investigated in youth trauma survivors. Analysis confirmed a factor comprising problems concentrating, sleeping difficulties, and mistrust as a predictor of a larger EPN difference between high arousing positive and low arousing neutral IAPS pictures using rapid serial visual presentation (RSVP). The EPN component was also modulated by sex. The findings also extend those of prior research on emotional processing confirming that EPN suppression can also be found in adolescents.

Type and timing of childhood maltreatment and reduced visual cortex volume in children and adolescents with reactive attachment disorder

Reactive attachment disorder (RAD) is a severe social functioning disorder associated with early childhood maltreatment where the child displays emotionally withdrawn/inhibited behaviors toward caregivers. Brain regions develop at different rates and regions undergoing rapid change may be particularly vulnerable during these times to stressors or adverse experiences. The aim of this study was to investigate the effect of type and timing of childhood adversities on structural alterations in regional gray matter (GM) volume in maltreated children with RAD. High-resolution magnetic resonance imaging datasets were obtained for children and adolescents with RAD (n = 21; mean age = 12.76 years) and typically developing (TD) control subjects (n = 22; mean age = 12.95 years). Structural images were analyzed using a whole-brain voxel-based morphometry approach and the type and timing of maltreatment, which may be more strongly associated with structural alterations, was assessed using random forest regression with conditional inference trees. Our findings revealed that there is a potential sensitive period between 5 and 7 years of age for GM volume reduction of the left primary visual cortex (BA17) due to maltreatment. We also found that the number of types of maltreatment had the most significant effect on GM volume reduction and that the second most significant variable was exposure to neglect. The present study provides the first evidence showing that type and timing of maltreatment have an important role in inducing structural abnormalities in children and adolescents with RAD.

Oscillatory magnetic brain activity is related to dissociative symptoms and childhood adversities - A study in women with multiple trauma

BACKGROUND

Individuals with trauma-related disorders are complex and heterogeneous; part of this complexity derives from additional psychopathology like dissociation as well as environmental adversities such as traumatic stress, experienced throughout the lifespan. Understanding the neurophysiological abnormalities in Post-traumatic stress disorder (PTSD) requires a simultaneous consideration of these factors.

METHODS

Resting state magnetoencephalography (MEG) recordings were obtained from 41 women with PTSD and comorbid depressive symptoms, and 16 healthy women. Oscillatory brain activity was extracted for five frequency bands and 11 source locations, and analyzed in relation to shutdown dissociation and adversity-related measures.

RESULTS

Dissociative symptoms were related to increased delta and lowered beta power. Adversity-related measures modulated theta and alpha oscillatory power (in particular childhood sexual abuse) and differed between patients and controls.

LIMITATIONS

Findings are based on women with comorbid depressive symptoms and therefore may not be applicable for men or groups with other clinical profiles. In respect to childhood adversities, we had no reliable source for the early infancy.

CONCLUSION

Trauma-related abnormalities in neural organization vary with both exposure to adversities as well as their potential to evoke ongoing shutdown responses.

Psychophysiological Reactivity and PTSD Symptom Severity among Young Women

Mixed findings with regard to cardiovascular reactivity (CVR) and posttraumatic stress disorder (PTSD) have suggested a need to further explore the nature of this relationship and factors that might explain differences in reactivity across and within samples. In the present study, the severity of PTSD symptoms was investigated in relation to CVR among young women. In addition, we examined whether severity within PTSD symptom clusters and level of dissociative symptoms were related to CVR. Heart rate, systolic and diastolic blood pressure, cardiac output (CO) and total peripheral resistance (TPR) reactivity in response to an oral speaking task were assessed for 58 young trauma-exposed civilian women with varying levels of PTSD symptomatology (from no symptoms to high severity of PTSD). The PTSD severity sub-scores for the DSM-V symptom clusters and total PTSD severity were based on structured interview (Clinician Administered PTSD Scale), and dissociative symptoms were assessed using the Dissociative Experiences Scale. Severity of total PTSD symptoms was associated with greater CO reactivity (r = .48, p < .01) and lower TPR reactivity (r = -.50, p < .01). Significant associations were not observed for heart rate or blood pressure. Results did not vary according to severity of symptoms within PTSD symptom cluster, with correlations for CO reactivity ranging from .40 to .49 and correlations for TPR reactivity ranging from -.40 to -.50 within symptom clusters. Dissociative symptoms were not significantly correlated with the CVR measures. Results partially supported the expectation that PTSD severity is one factor that would be associated with CVR, and suggest that reactivity for the underlying components of blood pressure (CO and TPR) provide additional information in probing stress reactivity in PTSD.

The shutdown dissociation scale (shut-d)

The evolutionary model of the defense cascade by Schauer and Elbert (2010) provides a theoretical frame for a short interview to assess problems underlying and leading to the dissociative subtype of posttraumatic stress disorder. Based on known characteristics of the defense stages "fright," "flag," and "faint," we designed a structured interview to assess the vulnerability for the respective types of dissociation. Most of the scales that assess dissociative phenomena are designed as self-report questionnaires. Their items are usually selected based on more heuristic considerations rather than a theoretical model and thus include anything from minor dissociative experiences to major pathological dissociation. The shutdown dissociation scale (Shut-D) was applied in several studies in patients with a history of multiple traumatic events and different disorders that have been shown previously to be prone to symptoms of dissociation. The goal of the present investigation was to obtain psychometric characteristics of the Shut-D (including factor structure, internal consistency, retest reliability, predictive, convergent and criterion-related concurrent validity). A total population of 225 patients and 68 healthy controls were accessed. Shut-D appears to have sufficient internal reliability, excellent retest reliability, high convergent validity, and satisfactory predictive validity, while the summed score of the scale reliably separates patients with exposure to trauma (in different diagnostic groups) from healthy controls. The Shut-D is a brief structured interview for assessing the vulnerability to dissociate as a consequence of exposure to traumatic stressors. The scale demonstrates high-quality psychometric properties and may be useful for researchers and clinicians in assessing shutdown dissociation as well as in predicting the risk of dissociative responding.