'I am afraid you will see the stain on my soul': Direct gaze neural processing in individuals with PTSD after moral injury recall

Direct eye contact is essential to understanding others' thoughts and feelings in social interactions. However, those with post-traumatic stress disorder (PTSD) and exposure to moral injury (MI) may exhibit altered theory-of-mind (ToM)/mentalizing processes and experience shame which precludes one's capacity for direct eye contact. We investigated blood oxygenation level-dependent (BOLD) responses associated with direct vs averted gaze using a virtual reality paradigm in individuals with PTSD (n = 28) relative to healthy controls (n = 18) following recall of a MI vs a neutral memory. Associations between BOLD responses and clinical symptomatology were also assessed. After MI recall, individuals with PTSD showed greater activation in the right temporoparietal junction as compared to controls (T = 4.83; pFDR < 0.001; k = 237) during direct gaze. No significant activation occurred during direct gaze after neutral memory recall. Further, a significant positive correlation was found between feelings of distress and right medial superior frontal gyrus activation in individuals with PTSD (T = 5.03; pFDR = 0.049; k = 123). These findings suggest that direct gaze after MI recall prompts compensatory ToM/mentalizing processing. Implications for future interventions aimed at mitigating the effects of PTSD on social functioning are discussed.

A randomized controlled trial of Deep Brain Reorienting: a neuroscientifically guided treatment for post-traumatic stress disorder

BACKGROUND

Advanced neuroscientific insights surrounding post-traumatic stress disorder (PTSD) and its associated symptomatology should beget psychotherapeutic treatments that integrate these insights into practice. Deep Brain Reorienting (DBR) is a neuroscientifically-guided psychotherapeutic intervention that targets the brainstem-level neurophysiological sequence that transpired during a traumatic event. Given that contemporary treatments have non-response rates of up to 50% and high drop-out rates of >18%, DBR is investigated as a putative candidate for effective treatment of some individuals with PTSD.

OBJECTIVE

To conduct an interim evaluation of the effectiveness of an eight-session clinical trial of videoconference-based DBR versus waitlist (WL) control for individuals with PTSD.

METHOD

Fifty-four individuals with PTSD were randomly assigned to DBR (N = 29) or WL (N = 25). At baseline, post-treatment, and three-month follow-up, participants' PTSD symptom severity was assessed using the Clinician Administered PTSD Scale (CAPS-5). This is an interim analysis of a clinical trial registered with the U. S. National Institute of Health (NCT04317820).

RESULTS

Significant between-group differences in CAPS-total and all subscale scores (re-experiencing, avoidance, negative alterations in cognitions/mood, alterations in arousal/reactivity) were found at post-treatment (CAPS-total: Cohen's d = 1.17) and 3-month-follow-up (3MFU) (CAPS-total: Cohen's d = 1.18). Significant decreases in CAPS-total and all subscale scores were observed within the DBR group pre - to post-treatment (36.6% CAPS-total reduction) and pre-treatment to 3MFU (48.6% CAPS-total reduction), whereas no significant decreases occurred in the WL group. After DBR, 48.3% at post-treatment and 52.0% at 3MFU no longer met PTSD criteria. Attrition was minimal with one participant not completing treatment; eight participants were lost to 3MFU.

CONCLUSIONS

These findings provide emerging evidence for the effectiveness of DBR as a well-tolerated treatment that is based on theoretical advances highlighting alterations to subcortical mechanisms in PTSD and associated symptomatology. Additional research utilizing larger sample sizes, neuroimaging data, and comparisons or adjacencies with other psychotherapeutic approaches is warranted.Trial registration: ClinicalTrials.gov identifier: NCT04317820..

Increased top-down control of emotions during symptom provocation working memory tasks following a RCT of alpha-down neurofeedback in PTSD

BACKGROUND

Posttraumatic stress disorder (PTSD) has been found to be associated with emotion under-modulation from the prefrontal cortex and a breakdown of the top-down control of cognition and emotion. Novel adjunct therapies such as neurofeedback (NFB) have been shown to normalize aberrant neural circuits that underlie PTSD psychopathology at rest. However, little evidence exists for NFB-linked neural improvements under emotionally relevant cognitive load. The current study sought to address this gap by examining the effects of alpha-down NFB in the context of an emotional n-back task.

METHODS

We conducted a 20-week double-blind randomized, sham-controlled trial of alpha-down NFB and collected neuroimaging data before and after the NFB protocol. Participants performed an emotional 1-back and 2-back working memory task, with interleaved trauma-neutral and trauma-relevant cues in the fMRI scanner. Data from 35 participants with a primary diagnosis of PTSD were analyzed in this study (n = 18 in the experimental group undergoing alpha-down NFB, n = 17 in the sham-control group).

RESULTS

Firstly, within-group analyses showed clinically significant reductions in PTSD symptom severity scores at the post-intervention timepoint and 3-month follow-up for the experimental group, and not for the sham-control group. The neuroimaging analyses revealed that alpha-down NFB enhanced engagement of top-down cognitive and emotional control centers, such as the dorsolateral prefrontal cortex (dlPFC), and improved integration of the anterior and posterior parts of the default mode network (DMN). Finally, our results also indicate that increased alpha-down NFB performance correlated with increased activity in brain regions involved in top-down control and bodily consciousness/embodied processing of self (TPJ and posterior insula).

CONCLUSION

This is the first study to provide mechanistic insights into how NFB may normalize dysfunctional brain activity and connectivity in PTSD under cognitive load with simultaneous symptom provocation, adding to a growing body of evidence supporting the therapeutic neuromodulatory effects of NFB. This preliminary study highlights the benefits of alpha-down NFB training as an adjunctive therapy for PTSD and warrants further investigation into its therapeutic effects on cognitive and emotion control in those with PTSD.

How Processing of Sensory Information From the Internal and External Worlds Shape the Perception and Engagement With the World in the Aftermath of Trauma: Implications for PTSD

Post-traumatic stress disorder (PTSD) is triggered by an individual experiencing or witnessing a traumatic event, often precipitating persistent flashbacks and severe anxiety that are associated with a fearful and hypervigilant presentation. Approximately 14–30% of traumatized individuals present with the dissociative subtype of PTSD, which is often associated with repeated or childhood trauma. This presentation includes symptoms of depersonalization and derealization, where individuals may feel as if the world or self is “dream-like” and not real and/or describe “out-of-body” experiences. Here, we review putative neural alterations that may underlie how sensations are experienced among traumatized individuals with PTSD and its dissociative subtype, including those from the outside world (e.g., touch, auditory, and visual sensations) and the internal world of the body (e.g., visceral sensations, physical sensations associated with feeling states). We postulate that alterations in the neural pathways important for the processing of sensations originating in the outer and inner worlds may have cascading effects on the performance of higher-order cognitive functions, including emotion regulation, social cognition, and goal-oriented action, thereby shaping the perception of and engagement with the world. Finally, we introduce a theoretical neurobiological framework to account for altered sensory processing among traumatized individuals with and without the dissociative subtype of PTSD.

Classifying heterogeneous presentations of PTSD via the default mode, central executive, and salience networks with machine learning

Intrinsic connectivity networks (ICNs), including the default mode network (DMN), the central executive network (CEN), and the salience network (SN) have been shown to be aberrant in patients with posttraumatic stress disorder (PTSD). The purpose of the current study was to a) compare ICN functional connectivity between PTSD, dissociative subtype PTSD (PTSD+DS) and healthy individuals; and b) to examine the use of multivariate machine learning algorithms in classifying PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. Our neuroimaging dataset consisted of resting-state fMRI scans from 186 participants [PTSD (n = 81); PTSD + DS (n = 49); and healthy controls (n = 56)]. We performed group-level independent component analyses to evaluate functional connectivity differences within each ICN. Multiclass Gaussian Process Classification algorithms within PRoNTo software were then used to predict the diagnosis of PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. When comparing the functional connectivity of ICNs between PTSD, PTSD+DS and healthy controls, we found differential patterns of connectivity to brain regions involved in emotion regulation, in addition to limbic structures and areas involved in self-referential processing, interoception, bodily self-consciousness, and depersonalization/derealization. Machine learning algorithms were able to predict with high accuracy the classification of PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. Our results suggest that alterations within intrinsic connectivity networks may underlie unique psychopathology and symptom presentation among PTSD subtypes. Furthermore, the current findings substantiate the use of machine learning algorithms for classifying subtypes of PTSD illness based on ICNs.

The effects of trauma on brain and body: A unifying role for the midbrain periaqueductal gray

Post-traumatic stress disorder (PTSD), a diagnosis that may follow the experience of trauma, has multiple symptomatic phenotypes. Generally, individuals with PTSD display symptoms of hyperarousal and of hyperemotionality in the presence of fearful stimuli. A subset of individuals with PTSD; however, elicit dissociative symptomatology (i.e., depersonalization, derealization) in the wake of a perceived threat. This pattern of response characterizes the dissociative subtype of the disorder, which is often associated with emotional numbing and hypoarousal. Both symptomatic phenotypes exhibit attentional threat biases, where threat stimuli are processed preferentially leading to a hypervigilant state that is thought to promote defensive behaviors during threat processing. Accordingly, PTSD and its dissociative subtype are thought to differ in their proclivity to elicit active (i.e., fight, flight) versus passive (i.e., tonic immobility, emotional shutdown) defensive responses, which are characterized by the increased and the decreased expression of the sympathetic nervous system, respectively. Moreover, active and passive defenses are accompanied by primarily endocannabinoid- and opioid-mediated analgesics, respectively. Through critical review of the literature, we apply the defense cascade model to better understand the pathological presentation of defensive responses in PTSD with a focus on the functioning of lower-level midbrain and extended brainstem systems.

Overlapping frontoparietal networks in response to oculomotion and traumatic autobiographical memory retrieval: implications for eye movement desensitization and reprocessing

Background: Oculomotor movements have been shown to aid in the retrieval of episodic memories, serving as sensory cues that engage frontoparietal brain regions to reconstruct visuospatial details of a memory. Frontoparietal brain regions not only are involved in oculomotion, but also mediate, in part, the retrieval of autobiographical episodic memories and assist in emotion regulation. Objective: We sought to investigate how oculomotion influences retrieval of traumatic memories by examining patterns of frontoparietal brain activation during autobiographical memory retrieval in post-traumatic stress disorder (PTSD) and in healthy controls. Method: Thirty-nine participants (controls, n = 19; PTSD, n = 20) recollected both neutral and traumatic/stressful autobiographical memories while cued simultaneously by horizontal and vertical oculomotor stimuli. The frontal (FEF) and supplementary (SEF) eye fields were used as seed regions for psychophysiological interaction analyses in SPM12. Results: As compared to controls, upon retrieval of a traumatic/stressful memory while also performing simultaneous horizontal eye movements, PTSD showed: i) increased SEF and FEF connectivity with the right dorsolateral prefrontal cortex, ii) increased SEF connectivity with the right dorsomedial prefrontal cortex, and iii) increased SEF connectivity with the right anterior insula. By contrast, as compared to PTSD, upon retrieval of a traumatic/stressful memory while also performing simultaneous horizontal eye movements, controls showed: i) increased FEF connectivity with the right posterior insula and ii) increased SEF connectivity with the precuneus. Conclusions: These findings provide a neurobiological account for how oculomotion may influence the frontoparietal cortical representation of traumatic memories. Implications for eye movement desensitization and reprocessing are discussed.

Altered Sense of Body Ownership and Agency in Posttraumatic Stress Disorder and Its Dissociative Subtype: A Rubber Hand Illusion Study

Traumatic experiences have been linked to the development of altered states of consciousness affecting bodily perception, including alterations in body ownership and in sense of agency, the conscious experience of the body as one's own and under voluntary control. Severe psychological trauma and prolonged distress may lead to posttraumatic stress disorder (PTSD). Together, symptoms of derealization and, related specifically to the sense of body ownership and agency, of depersonalization (where parts of the body or the entire body itself is perceived as detached and out of control), constitute the dissociative subtype (PTSD+DS). In this study, we explored the Rubber Hand Illusion, an experimental paradigm utilized to manipulate sense of body ownership in PTSD (n = 4) and PTSD+DS (n = 6) as compared to healthy controls (n = 7). Perceived finger location and self-report questionnaires were used as behavioral and subjective measures of the illusion, respectively. In addition, the correlation between the illusion's effect and sense of agency as a continuous feeling of controlling one's own body movements was explored. Here, a lower illusion effect was observed in the PTSD as compared to the control group after synchronous stimulation for both the proprioceptive drift and subjectively perceived illusion. Moreover, by both proprioceptive drift and by subjective ratings, the PTSD+DS group showed a response characterized by high variance, ranging from a very strong to a very weak effect of the illusion. Finally, sense of agency showed a trend toward a negative correlation with the strength of the illusion as subjectively perceived by participants with PTSD and PTSD+DS. These findings suggest individuals with PTSD may, at times, maintain a rigid representation of the body as an avoidance strategy, with top-down cognitive processes weakening the impact of manipulation of body ownership. By contrast, the response elicited in PTSD+DS appeared to be driven by either an increased vulnerability to manipulation of embodiment or by a dominant top-down cognitive representation of the body, with disruption of multisensory integration processes likely in both cases. Taken together, these findings further our understanding of bodily consciousness in PTSD and its dissociative subtype and highlight the supportive role played by sense of agency for the maintenance of body ownership.

Adherence to, and outcomes of, a galactomannan screening protocol in high-risk hematology patients

Background

A twice-weekly galactomannan (gm) screening protocol was implemented in high-risk hematology inpatients. Study objectives were to determine adherence to the protocol, use of selected resources, and patient outcomes.

Methods

This retrospective cohort study compared outcomes of interest before and after implementation of gm screening. Adults undergoing matched related allogeneic hematopoietic stem-cell transplantation or induction chemotherapy for acute leukemia were eligible. Patients could be enrolled more than once and were evaluated as episodes. Adherence to the gm protocol was assessed in post-implementation episodes. Use of broad-spectrum antifungals (bsafs), consultations (infectious diseases, respirology), and diagnostic procedures (computed tomography imaging, bronchoalveolar lavage) were compared between phases, as were the patient outcomes of all-cause mortality and clinical success (alive and not taking a bsaf).

Results

Of 182 episodes consecutively screened, 70 per phase were enrolled. Clinical characteristics and duration of assessment were similar for the phases. Full or partial adherence to the protocol was observed in 61 post-implementation episodes (87%), with full adherence in 40 episodes (57%). More episodes in the pre-implementation phase than in the post-implementation phase involved receipt of bsafs, consultations, and diagnostics (27% vs. 7%, p = 0.02; 46% vs. 26%, p = 0.014; and 46% vs. 31%, p = 0.083 respectively). Although mortality was similar in the two phases, clinical success at the final assessment was observed in fewer pre-implementation than post-implementation episodes (79% vs. 98%, p < 0.001).

Conclusions

Implementation of a gm screening protocol was feasible and associated with significantly fewer episodes involving receipt of bsafs and consultations, and with significantly more episodes showing clinical success.

Resting-state functional connectivity of the bed nucleus of the stria terminalis in post-traumatic stress disorder and its dissociative subtype

The bed nucleus of the stria terminals (BNST) is a subcortical structure involved in anticipatory and sustained reactivity to threat and is thus essential to the understanding of anxiety and stress responses. Although chronic stress and anxiety represent a hallmark of post-traumatic stress disorder (PTSD), to date, few studies have examined the functional connectivity of the BNST in PTSD. Here, we used resting state functional Magnetic Resonance Imaging (fMRI) to investigate the functional connectivity of the BNST in PTSD (n = 70), its dissociative subtype (PTSD + DS) (n = 41), and healthy controls (n = 50). In comparison to controls, PTSD showed increased functional connectivity of the BNST with regions of the reward system (ventral and dorsal striatum), possibly underlying stress-induced reward-seeking behaviors in PTSD. By contrast, comparing PTSD + DS to controls, we observed increased functional connectivity of the BNST with the claustrum, a brain region implicated in consciousness and a primary site of kappa-opioid receptors, which are critical to the dynorphin-mediated dysphoric stress response. Moreover, PTSD + DS showed increased functional connectivity of the BNST with brain regions involved in attention and salience detection (anterior insula and caudate nucleus) as compared to PTSD and controls. Finally, BNST functional connectivity positively correlated with default-mode network regions as a function of state identity dissociation, suggesting a role of BNST networks in the disruption of self-relevant processing characterizing the dissociative subtype. These findings represent an important first step in elucidating the role of the BNST in aberrant functional networks underlying PTSD and its dissociative subtype.

Superior colliculus resting state networks in post-traumatic stress disorder and its dissociative subtype

OBJECTIVES

The innate alarm system (IAS) models the neurocircuitry involved in threat processing in posttraumatic stress disorder (PTSD). Here, we investigate a primary subcortical structure of the IAS model, the superior colliculus (SC), where the SC is thought to contribute to the mechanisms underlying threat-detection in PTSD. Critically, the functional connectivity between the SC and other nodes of the IAS remains unexplored.

EXPERIMENTAL DESIGN

We conducted a resting-state fMRI study to investigate the functional architecture of the IAS, focusing on connectivity of the SC in PTSD (n = 67), its dissociative subtype (n = 41), and healthy controls (n = 50) using region-of-interest seed-based analysis.

PRINCIPAL OBSERVATIONS

We observed group-specific resting state functional connectivity between the SC for both PTSD and its dissociative subtype, indicative of dedicated IAS collicular pathways in each group of patients. When comparing PTSD to its dissociative subtype, we observed increased resting state functional connectivity between the left SC and the right dorsolateral prefrontal cortex (DLPFC) in PTSD. The DLPFC is involved in modulation of emotional processes associated with active defensive responses characterising PTSD. Moreover, when comparing PTSD to its dissociative subtype, increased resting state functional connectivity was observed between the right SC and the right temporoparietal junction in the dissociative subtype. The temporoparietal junction is involved in depersonalization responses associated with passive defensive responses typical of the dissociative subtype.

CONCLUSIONS

Our findings suggest that unique resting state functional connectivity of the SC parallels the unique symptom profile and defensive responses observed in PTSD and its dissociative subtype. Hum Brain Mapp 39:563-574, 2018. © 2017 Wiley Periodicals, Inc.

Dynamic causal modeling in PTSD and its dissociative subtype: Bottom-up versus top-down processing within fear and emotion regulation circuitry

OBJECTIVE

Posttraumatic stress disorder (PTSD) is associated with decreased top-down emotion modulation from medial prefrontal cortex (mPFC) regions, a pathophysiology accompanied by hyperarousal and hyperactivation of the amygdala. By contrast, PTSD patients with the dissociative subtype (PTSD + DS) often exhibit increased mPFC top-down modulation and decreased amygdala activation associated with emotional detachment and hypoarousal. Crucially, PTSD and PTSD + DS display distinct functional connectivity within the PFC, amygdala complexes, and the periaqueductal gray (PAG), a region related to defensive responses/emotional coping. However, differences in directed connectivity between these regions have not been established in PTSD, PTSD + DS, or controls.

METHODS

To examine directed (effective) connectivity among these nodes, as well as group differences, we conducted resting-state stochastic dynamic causal modeling (sDCM) pairwise analyses of coupling between the ventromedial (vm)PFC, the bilateral basolateral and centromedial (CMA) amygdala complexes, and the PAG, in 155 participants (PTSD [n = 62]; PTSD + DS [n = 41]; age-matched healthy trauma-unexposed controls [n = 52]).

RESULTS

PTSD was characterized by a pattern of predominant bottom-up connectivity from the amygdala to the vmPFC and from the PAG to the vmPFC and amygdala. Conversely, PTSD + DS exhibited predominant top-down connectivity between all node pairs (from the vmPFC to the amygdala and PAG, and from the amygdala to the PAG). Interestingly, the PTSD + DS group displayed the strongest intrinsic inhibitory connections within the vmPFC.

CONCLUSIONS

These results suggest the contrasting symptom profiles of PTSD and its dissociative subtype (hyper- vs. hypo-emotionality, respectively) may be driven by complementary changes in directed connectivity corresponding to bottom-up defensive fear processing versus enhanced top-down regulation. Hum Brain Mapp 38:5551-5561, 2017. © 2017 Wiley Periodicals, Inc.

fMRI functional connectivity of the periaqueductal gray in PTSD and its dissociative subtype

BACKGROUND

Posttraumatic stress disorder (PTSD) is associated with hyperarousal and active fight or flight defensive responses. By contrast, the dissociative subtype of PTSD, characterized by depersonalization and derealization symptoms, is frequently accompanied by additional passive or submissive defensive responses associated with autonomic blunting. Here, the periaqueductal gray (PAG) plays a central role in defensive responses, where the dorsolateral (DL-PAG) and ventrolateral PAG (VL-PAG) are thought to mediate active and passive defensive responses, respectively.

METHODS

We examined PAG subregion (dorsolateral and ventrolateral) resting-state functional connectivity in three groups: PTSD patients without the dissociative subtype (n = 60); PTSD patients with the dissociative subtype (n = 37); and healthy controls (n = 40) using a seed-based approach via PickAtlas and SPM12.

RESULTS

All PTSD patients showed extensive DL- and VL-PAG functional connectivity at rest with areas associated with emotional reactivity and defensive action as compared to controls (n = 40). Although all PTSD patients demonstrated DL-PAG functional connectivity with areas associated with initiation of active coping strategies and hyperarousal (e.g., dorsal anterior cingulate; anterior insula), only dissociative PTSD patients exhibited greater VL-PAG functional connectivity with brain regions linked to passive coping strategies and increased levels of depersonalization (e.g., temporoparietal junction; rolandic operculum).

CONCLUSIONS

These findings suggest greater defensive posturing in PTSD patients even at rest and demonstrate that those with the dissociative subtype show unique patterns of PAG functional connectivity when compared to those without the subtype. Taken together, these findings represent an important first step toward identifying neural and behavioral targets for therapeutic interventions that address defensive strategies in trauma-related disorders.

"I can't tell whether it's my hand": a pilot study of the neurophenomenology of body representation during the rubber hand illusion in trauma-related disorders

BACKGROUND

Early traumatic experiences are thought to be causal factors in the development of trauma-related dissociative experiences, including depersonalization and derealization. The rubber hand illusion (RHI), a well-known paradigm that measures multi-sensorial integration of a rubber hand into one's own body representation, has been used to investigate alterations in the experience of body ownership and of body representation. Critically, however, it has never been studied in individuals with trauma-related disorders.

OBJECTIVE

To investigate body representation distortions occurring in trauma-related disorders in response to the RHI.

METHOD

The RHI was administered to three individuals with the dissociative subtype of posttraumatic stress disorder (PTSD), and subjective, behavioral, cardiovascular and skin conductance responses were recorded.

RESULTS

Participants' subjective experiences of the RHI were differentiated and complex. The illusion was induced following both synchronous and asynchronous brushing and variably evoked subjective distress, depersonalization and derealization experiences, tonic immobility, increased physiological arousal and flashbacks.

CONCLUSIONS

The present findings point towards the RHI as a strong provocation stimulus that elicits individual patterns of symptom presentation, including experiences of distress and dissociation, in individuals with trauma-related disorders, including the dissociative subtype of PTSD.

HIGHLIGHTS OF THE ARTICLE

The rubber hand illusion (RHI) elicits distress, tonic immobility, depersonalization and derealization, and autonomic responses in individuals with trauma-related disorders, including the dissociative subtype of posttraumatic stress disorder (PTSD). RHI effects related to body misrepresentation may trigger altered experiences related to body ownership. The RHI represents a promising paradigm for studying the neurophenomenology of body distortion in individuals experiencing trauma-related altered states of consciousness (TRASC).