Opponent Effects of Hyperarousal and Re-experiencing on Affective Habituation in Posttraumatic Stress Disorder

Differential posttraumatic stress disorder symptom cluster response to stellate ganglion block: secondary analysis of a randomized controlled trial

Empirically supported treatments for posttraumatic stress disorder (PTSD) exist, but research suggests these therapies are less effective, acceptable, and feasible to deliver to active duty service members (SMs) compared to civilians. Stellate ganglion block (SGB) procedure, in which a local anesthetic is injected around the cervical sympathetic chain or stellate ganglion to temporarily inhibit sympathetic nervous activity, is gaining popularity as an alternative PTSD treatment in military settings. However, it is unknown whether certain PTSD symptoms are more responsive to SGB than others. The current study involved a secondary analysis of data collected from a previous randomized controlled trial of SGB compared to sham (normal saline) injection (N = 113 SMs). PTSD symptoms were assessed via clinical interview and self-report at baseline and 8 weeks post-SGB or sham. Logistic regression analyses showed that the marked alterations in arousal and reactivity PTSD symptom cluster demonstrated the greatest symptom severity reductions after SGB, relative to sham. The reexperiencing cluster also showed pronounced response to SGB in clinician-rated but not self-reported outcomes. Post-hoc item-level analyses suggested that arousal and reactivity cluster findings were driven by reductions in hypervigilance, concentration difficulties, and sleep disturbance, whereas clinician-rated reexperiencing cluster findings were driven by reductions in physiological reactions to trauma cues, emotional reactions to trauma cues, and intrusions. Our findings align with a burgeoning literature positioning SGB as a potential novel or adjunctive PTSD treatment. Results could guide future hypothesis-driven research on mediators of therapeutic change during SGB for PTSD symptoms in SMs.

Development of a Scale to Examine Responses to Bodily Sensations

OBJECTIVE

Individual differences in the perception of bodily sensations is known to be associated with affective symptomatology. However, the way people psychologically respond to everyday bodily sensations has not been examined in a systematic and balanced way. Thus, we developed the Bodily Sensations Response Scale (BSRS) to evaluate participants' self-reported cognitive, emotional, and behavioral responses to their bodily sensations. We investigated the scale's factor structure and its psychometric properties in two studies.

METHOD

In Study 1, 297 participants completed the 50-item BSRS and exploratory factor analysis (EFA) was performed on the responses. In Study 2 (N = 284), confirmatory factor analysis (CFA) was used to confirm the factor structure of the 32-item BSRS identified in Study 1.

RESULTS

In Study 1, the EFA identified a 32-item three-factor solution as the best fit for the data. Factor 1 described a defeat response to bodily sensations, Factor 2 described an acceptance response, and Factor 3 described a sensitization response. In Study 2, the three-factor solution was shown not to be parsimonious. Rather, CFA identified that the 27-item BSRS had two interpretable factors (Defeat and Acceptance) that explained participants' psychological responses to bodily sensations. The Defeat subscale was moderately to strongly correlated with awareness of bodily sensations (i.e., Body Perception Questionnaire-Short Form scores) and depression, anxiety, and stress symptom severity (i.e., Depression Anxiety Stress Scales-21 scores), whereas the Acceptance subscale was unrelated or only slightly negatively correlated to awareness of bodily sensations and depression, anxiety, and stress symptoms.

CONCLUSION

The 27-item BSRS provides a psychometrically robust assessment of the way in which people psychologically respond to everyday bodily sensations. The measure can assist researchers to better understand how people psychologically process their salient bodily sensations and how this is linked to psychopathology.

Posterior cingulate cortex targeted real-time fMRI neurofeedback recalibrates functional connectivity with the amygdala, posterior insula, and default-mode network in PTSD

BACKGROUND

Alterations within large-scale brain networks-namely, the default mode (DMN) and salience networks (SN)-are present among individuals with posttraumatic stress disorder (PTSD). Previous real-time functional magnetic resonance imaging (fMRI) and electroencephalography neurofeedback studies suggest that regulating posterior cingulate cortex (PCC; the primary hub of the posterior DMN) activity may reduce PTSD symptoms and recalibrate altered network dynamics. However, PCC connectivity to the DMN and SN during PCC-targeted fMRI neurofeedback remains unexamined and may help to elucidate neurophysiological mechanisms through which these symptom improvements may occur.

METHODS

Using a trauma/emotion provocation paradigm, we investigated psychophysiological interactions over a single session of neurofeedback among PTSD (n = 14) and healthy control (n = 15) participants. We compared PCC functional connectivity between regulate (in which participants downregulated PCC activity) and view (in which participants did not exert regulatory control) conditions across the whole-brain as well as in a priori specified regions-of-interest.

RESULTS

During regulate as compared to view conditions, only the PTSD group showed significant PCC connectivity with anterior DMN (dmPFC, vmPFC) and SN (posterior insula) regions, whereas both groups displayed PCC connectivity with other posterior DMN areas (precuneus/cuneus). Additionally, as compared with controls, the PTSD group showed significantly greater PCC connectivity with the SN (amygdala) during regulate as compared to view conditions. Moreover, linear regression analyses revealed that during regulate as compared to view conditions, PCC connectivity to DMN and SN regions was positively correlated to psychiatric symptoms across all participants.

CONCLUSION

In summary, observations of PCC connectivity to the DMN and SN provide emerging evidence of neural mechanisms underlying PCC-targeted fMRI neurofeedback among individuals with PTSD. This supports the use of PCC-targeted neurofeedback as a means by which to recalibrate PTSD-associated alterations in neural connectivity within the DMN and SN, which together, may help to facilitate improved emotion regulation abilities in PTSD.

A longitudinal mediation study of peer victimization and resting-state functional connectivity as predictors of development of adolescent psychopathology

Background

Peer victimization (PV) is associated with alterations in neural responses in regions subserving emotional regulatory processes and with increased risk of psychopathology during adolescence. The present study examined the longitudinal mediating effects of resting-state functional connectivity (rsFC) between adolescent PV and subsequent internalizing (depression and anxiety), and externalizing (conduct and hyperactivity/inattention) symptoms.

Methods

151 adolescents (baseline mean age 12-14; 54% males) were assessed and imaged three times during a five-year period. We focused on rsFC of a priori determined Regions-of-Interest (ROIs) guided by the literature (i.e., amygdala, anterior and posterior insula, anterior cingulate cortex, and medial prefrontal cortex). Multilevel mediation (MLM) analyses simultaneously examined the between-person, concurrent within-person, and lagged within-person associations between PV and internalizing/externalizing symptoms through changes in couplings of the amygdala with the other four ROIs. All models controlled for the effects of self-reported childhood maltreatment and sex differences.

Results

An increased rsFC of the amygdala-posterior insula significantly mediated the lagged within-person association of PV and internalizing symptoms (β = 0.144; 95% CI [0.018, 0.332]). This effect was significant regardless of childhood maltreatment, concurrent externalizing symptoms, and sex differences. The rsFC did not mediate the relationship between PV and externalizing symptoms.

Conclusions

Results of this study suggest that adolescent PV may lead to long-lasting maladaptive neural communication between emotional response and sensory perception of pain (i.e., bottom-up emotion regulation) and that these neural responses may serve as unique markers for increased internalizing symptoms that appear in later adolescence in peer-victimized youth. These findings have implications for interventions targeting internalizing symptoms in victimized adolescents.

Unrelenting Fear Under Stress: Neural Circuits and Mechanisms for the Immediate Extinction Deficit

Therapeutic interventions for disorders of fear and anxiety rely on behavioral approaches that reduce pathological fear memories. For example, learning that threat-predictive stimuli are no longer associated with aversive outcomes is central to the extinction of conditioned fear responses. Unfortunately, fear memories are durable, long-lasting, and resistant to extinction, particularly under high levels of stress. This is illustrated by the “immediate extinction deficit,” which is characterized by a poor long-term reduction of conditioned fear when extinction procedures are attempted within hours of fear conditioning. Here, I will review recent work that has provided new insight into the neural mechanisms underlying resistance to fear extinction. Emerging studies reveal that locus coeruleus norepinephrine modulates amygdala-prefrontal cortical circuits that are critical for extinction learning. These data suggest that stress-induced activation of brain neuromodulatory systems biases fear memory at the expense of extinction learning. Behavioral and pharmacological strategies to reduce stress in patients undergoing exposure therapy might improve therapeutic outcomes.

Shorter Telomeres Related to Posttraumatic Stress Disorder Re-experiencing Symptoms in Sexually Assaulted Civilian Women

Telomeres are short tandem repeats of "TTAGGG" that protect the chromosome ends from deterioration or fusion of chromosomes. Their repeat length shortens with cell division acting as a biomarker of cellular aging. Traumatic stress events during adulthood or childhood have been associated with posttraumatic stress disorder (PTSD) and short leukocyte telomere length (LTL). This study investigated whether LTL was associated with PTSD in a Brazilian sample of sexually assaulted civilian women at two time points: baseline and 1-year follow-up. At baseline, we assessed 64 women with PTSD following sexual assault (cases) and 60 women with no previous history of sexual trauma or mental disorders (healthy controls - HC). At follow-up visit, 13 persistent PTSD cases, 11 HCs, and 11 PTSD remitters patients were evaluated. PTSD diagnosis and severity were assessed using Mini International Neuropsychiatric Interview (Diagnostic and Statistical Manual of Mental Disorders III/IV criteria) and Clinician-Administered PTSD Scale for DSM-5 (CAPS-5), respectively. LTL was measured using multiplex real-time polymerase chain reaction (PCR). In the baseline analysis, we observed that LTL was associated with re-experiencing symptoms (B = -0.16; confidence interval (CI) 95% = -0.027--0.005; Bonferroni-adjusted p-value = 0.02), but no association was observed between other PTSD symptoms and LTL. In the longitudinal analysis, telomere shortening was no longer observed in patients with PTSD and PTSD remitters. In conclusion, our findings indicate that shorter baseline LTL is associated with early stage of PTSD re-experiencing symptoms in recently sexually assaulted women.

A systematic review of the neural correlates of sexual minority stress: towards an intersectional minority mosaic framework with implications for a future research agenda

BACKGROUND

Systemic oppression, particularly towards sexual minorities, continues to be deeply rooted in the bedrock of many societies globally. Experiences with minority stressors (e.g. discrimination, hate-crimes, internalized homonegativity, rejection sensitivity, and microaggressions or everyday indignities) have been consistently linked to adverse mental health outcomes. Elucidating the neural adaptations associated with minority stress exposure will be critical for furthering our understanding of how sexual minorities become disproportionately affected by mental health burdens.

Following PRISMA-guidelines, we systematically reviewed published neuroimaging studies that compared neural dynamics among sexual minority and heterosexual populations, aggregating information pertaining to any measurement of minority stress and relevant clinical phenomena.

RESULTS

Only 1 of 13 studies eligible for inclusion examined minority stress directly, where all other studies focused on investigating the neurobiological basis of sexual orientation. In our narrative synthesis, we highlight important themes that suggest minority stress exposure may be associated with decreased activation and functional connectivity within the default-mode network (related to the sense-of-self and social cognition), and summarize preliminary evidence related to aberrant neural dynamics within the salience network (involved in threat detection and fear processing) and the central executive network (involved in executive functioning and emotion regulation). Importantly, this parallels neural adaptations commonly observed among individuals with posttraumatic stress disorder (PTSD) in the aftermath of trauma and supports the inclusion of insidious forms of trauma related to minority stress within models of PTSD.

CONCLUSIONS

Taken together, minority stress may have several shared neuropsychological pathways with PTSD and stress-related disorders. Here, we outline a detailed research agenda that provides an overview of literature linking sexual minority stress to PTSD and insidious trauma, moral affect (including shame and guilt), and mental health risk/resiliency, in addition to racial, ethnic, and gender related minority stress. Finally, we propose a novel minority mosaic framework designed to inform future directions of minority stress neuroimaging research from an intersectional lens.

The Association between Child and Parent Psychiatric Disorders in Families Exposed to Flood and/or Dioxin

Associations of disaster mental health sequelae between children and their parents have been demonstrated, but not using full diagnostic assessment. This study examined children and their parents after a series of disasters in 1982 to investigate associations of their psychiatric outcomes. Members of 169 families exposed to floods and/or dioxin or no disaster were assessed in 1986–1987 with structured diagnostic interviews. This vintage dataset collected several decades ago provides new information to this field because of the methodological rigor that is unparalleled in this literature. Disaster-related PTSD and incident postdisaster disorders in children were associated, respectively with disaster-related PTSD and incident postdisaster disorders in the chief caregiver and mother. More flood-only than dioxin-only exposed parents reported great harm by the disaster, but neither children nor parents in these two groups differed in incident psychiatric disorders. Although this study did not determine the direction of causal influences, its findings suggest that clinicians working with disaster-exposed families should work with children and adult members together, as their mental health outcomes may be intertwined.

A randomized, controlled trial of alpha-rhythm EEG neurofeedback in posttraumatic stress disorder: A preliminary investigation showing evidence of decreased PTSD symptoms and restored default mode and salience network connectivity using fMRI

OBJECTIVE

The default-mode network (DMN) and salience network (SN) have been shown to display altered connectivity in posttraumatic stress disorder (PTSD). Restoring aberrant connectivity within these networks with electroencephalogram neurofeedback (EEG-NFB) has been shown previously to be associated with acute decreases in symptoms. Here, we conducted a double-blind, sham-controlled randomized trial of alpha-rhythm EEG-NFB in participants with PTSD (n = 36) over 20-weeks. Our aim was to provide mechanistic evidence underlying clinical improvements by examining changes in network connectivity via fMRI.

METHODS

We randomly assigned participants with a primary diagnosis of PTSD to either the experimental group (n = 18) or sham-control group (n = 18). We collected resting-state fMRI scans pre- and post-NFB intervention, for both the experimental and sham-control PTSD groups. We further compared baseline brain connectivity measures pre-NFB to age-matched healthy controls (n = 36).

RESULTS

With regard to the primary outcome measure of PTSD severity, we found a significant main effect of time in the absence of a group × time interaction. Nevertheless, we found significantly decreased PTSD severity scores in the experimental NFB group only, when comparing post-NFB (dz = 0.71) and 3-month follow-up scores (dz = 0.77) to baseline measures. Interestingly, we found evidence to suggest a shift towards normalization of DMN and SN connectivity post-NFB in the experimental group only. Both decreases in PTSD severity and NFB performance were correlated to DMN and SN connectivity post-NFB in the experimental group. Critically, remission rates of PTSD were significant higher in the experimental group (61.1%) as compared to the sham-control group (33.3%).

CONCLUSION

The current study shows mechanistic evidence for therapeutic changes in DMN and SN connectivity that are known to be associated with PTSD psychopathology with no patient dropouts. This preliminary investigation merits further research to demonstrate fully the clinical efficacy of EEG-NFB as an adjunctive therapy for PTSD.

Rt-fMRI neurofeedback-guided cognitive reappraisal training modulates amygdala responsivity in posttraumatic stress disorder

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We found neurofeedback-specific attenuation of amygdala responses.

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Trauma symptoms and the affective state improved in patients at one-month follow-up.

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Reduced amygdala responses were associated with improved well-being at follow-up.

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75% of individuals with PTSD used the learned strategies in daily life.

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Left lateral prefrontal cortex responses were reduced during neurofeedback training.

Background

Traumatic experiences are associated with neurofunctional dysregulations in key regions of the emotion regulation circuits. In particular, amygdala responsivity to negative stimuli is exaggerated while engagement of prefrontal regulatory control regions is attenuated. Successful application of emotion regulation (ER) strategies may counteract this disbalance, however, application of learned strategies in daily life is hampered in individuals afflicted by posttraumatic stress disorder (PTSD). We hypothesized that a single session of real-time fMRI (rtfMRI) guided upregulation of prefrontal regions during an emotion regulation task enhances self-control during exposure to negative stimuli and facilitates transfer of the learned ER skills to daily life.

Methods

In a cross-over design, individuals with a PTSD diagnosis after a single traumatic event (n = 20) according to DSM-IV-TR criteria and individuals without a formal psychiatric diagnosis (n = 21) underwent a cognitive reappraisal training. In randomized order, all participants completed two rtfMRI neurofeedback (NF) runs targeting the left lateral prefrontal cortex (lPFC) and two control runs without NF (NoNF) while using cognitive reappraisal to reduce their emotional response to negative scenes. During the NoNF runs, two %%-signs were displayed instead of the two-digit feedback (FB) to achieve a comparable visual stimulation. The project aimed at defining the clinical potential of the training according to three success markers: (1) NF induced changes in left lateral prefrontal cortex and bilateral amygdala activity during the regulation of aversive scenes compared to cognitive reappraisal alone (primary registered outcome), (2) associated changes on the symptomatic and behavioral level such as indicated by PTSD symptom severity and affect ratings, (3) clinical utility such as indicated by perceived efficacy, acceptance, and transfer to daily life measured four weeks after the training.

Results

In comparison to the reappraisal without feedback, a neurofeedback-specific decrease in the left lateral PFC (d = 0.54) alongside an attenuation of amygdala responses (d = 0.33) emerged. Reduced amygdala responses during NF were associated with symptom improvement (r = −0.42) and less negative affect (r = −0.63) at follow-up. The difference in symptom scores exceeds requirements for a minimal clinically important difference and corresponds to a medium effect size (d = 0.64). Importantly, 75% of individuals with PTSD used the strategies in daily life during a one-month follow-up period and perceived the training as efficient.

Conclusion

Our findings suggest beneficial effects of the NF training indicated by reduced amygdala responses that were associated with improved symptom severity and affective state four weeks after the NF training as well as patient-centered perceived control during the training, helpfulness and application of strategies in daily life. However, reduced prefrontal involvement was unexpected. The study suggests good tolerability of the training protocol and potential for clinical use in the treatment of PTSD.

Estradiol Modulates Neural and Behavioral Arousal in Women With Posttraumatic Stress Disorder During a Fear Learning and Extinction Task

BACKGROUND

Fear responding in posttraumatic stress disorder (PTSD) is sexually heterogeneous and varies with hormonal fluctuations throughout the menstrual cycle. While research suggests that estrogen levels affect PTSD symptoms among women, there is a dearth of research on modulatory effects of estrogen on fear responding among women with PTSD, and neural outcome measures are lacking.

METHODS

A sample of 42 women with PTSD underwent 2 consecutive alternating blocks of fear conditioning and extinction training, during which a CS+ conditioned stimulus, but not a CS-, predicted the occurrence of an electric shock in an acquisition context but not in an extinction context. Assayed saliva determined estradiol levels. Skin conductance response and whole-brain voxelwise activity during functional magnetic resonance imaging were outcome variables in linear mixed-effects models, with estradiol level, PTSD severity, and task contrasts as predictors.

RESULTS

Skin conductance response exhibited a significant estradiol × PTSD severity × habituation interaction (t = 3.180, p = .002), such that PTSD severity was correlated with increased arousal responding between training blocks among women with lower estradiol (t = -3.985, p < .001) but not higher estradiol (t = 0.550, p = .583). Voxelwise activity also demonstrated an identical three-way interaction within dorsomedial prefrontal cortex and anterior insula clusters. The skin conductance response and imaging interactions between PTSD severity and estradiol were not specific to conditioned stimulus type or context.

CONCLUSIONS

Estradiol moderated the relationship between PTSD severity and arousal response habituation between fear conditioning and extinction training sessions, such that high estradiol protected against the negative impact of severe PTSD symptoms on fear habituation. These findings suggest that estrogen enhances habituation among women with severe PTSD, potentially influencing the efficacy of extinction-based therapies.