Transdiagnostic trauma severity in anxiety and mood disorders: Functional brain activity during emotional scene processing

Sex differences in the effects of individual anxiety state on regional responses to negative emotional scenes

BACKGROUND

Men and women are known to show differences in the incidence and clinical manifestations of mood and anxiety disorders. Many imaging studies have investigated the neural correlates of sex differences in emotion processing. However, it remains unclear how anxiety might impact emotion processing differently in men and women.

METHOD

We recruited 119 healthy adults and assessed their levels of anxiety using State-Trait Anxiety Inventory (STAI) State score. With functional magnetic resonance imaging (fMRI), we examined regional responses to negative vs. neutral (Neg-Neu) picture matching in the Hariri task. Behavioral data were analyzed using regression and repeated-measures analysis of covariance with age as a covariate, and fMRI data were analyzed using a full-factorial model with sex as a factor and age as a covariate.

RESULTS

Men and women did not differ in STAI score, or accuracy rate or reaction time (RT) (Neg-Neu). However, STAI scores correlated positively with RT (Neg-Neu) in women but not in men. Additionally, in women, STAI score correlated positively with lingual gyrus (LG) and negatively with medial prefrontal cortex (mPFC) and superior frontal gyrus (SFG) activity during Neg vs. Neu trials. The parameter estimates (βs) of mPFC also correlated with RT (Neg-Neu) in women but not in men. Generalized psychophysiological interaction (gPPI) analysis in women revealed mPFC connectivity with the right inferior frontal gyrus, right SFG, and left parahippocampal gyrus during Neg vs. Neu trials in positive correlation with both STAI score and RT (Neg-Neu). In a mediation analysis, mPFC gPPI but not mPFC activity fully mediated the association between STAI scores and RT (Neg-Neu).

CONCLUSION

With anxiety affecting the behavioral and neural responses to negative emotions in women but not in men and considering the known roles of the mPFC in emotion regulation, we discussed heightened sensitivity and regulatory demands during negative emotion processing as neurobehavioral markers of anxiety in women.

Precision psychiatry and Research Domain Criteria: Implications for clinical trials and future practice

Psychiatric disorders are associated with significant social and economic burdens, many of which are related to issues with current diagnosis and treatments. The coronavirus (COVID-19) pandemic is estimated to have increased the prevalence and burden of major depressive and anxiety disorders, indicating an urgent need to strengthen mental health systems globally. To date, current approaches adopted in drug discovery and development for psychiatric disorders have been relatively unsuccessful. Precision psychiatry aims to tailor healthcare more closely to the needs of individual patients and, when informed by neuroscience, can offer the opportunity to improve the accuracy of disease classification, treatment decisions, and prevention efforts. In this review, we highlight the growing global interest in precision psychiatry and the potential for the National Institute of Health-devised Research Domain Criteria (RDoC) to facilitate the implementation of transdiagnostic and improved treatment approaches. The need for current psychiatric nosology to evolve with recent scientific advancements and increase awareness in emerging investigators/clinicians of the value of this approach is essential. Finally, we examine current challenges and future opportunities of adopting the RDoC-associated translational and transdiagnostic approaches in clinical studies, acknowledging that the strength of RDoC is that they form a dynamic framework of guiding principles that is intended to evolve continuously with scientific developments into the future. A collaborative approach that recruits expertise from multiple disciplines, while also considering the patient perspective, is needed to pave the way for precision psychiatry that can improve the prognosis and quality of life of psychiatric patients.

Sensory alterations in post-traumatic stress disorder

PTSD is characterized by difficulties in accurately evaluating the threat value of sensory stimuli. While the role of canonical fear and threat neural circuitry in this ability has been well studied, recent lines of evidence suggest a need to include more emphasis on sensory processing in the conceptualization of PTSD symptomology. Specifically, studies have demonstrated a strong association between variability in sensory processing regions and the severity of PTSD symptoms. In this review, we summarize recent findings that underscore the importance of sensory processing in PTSD, in addition to the structural and functional characteristics of associated sensory brain regions. First, we discuss the link between PTSD and various behavioral aspects of sensory processing. This is followed by a discussion of recent findings that link PTSD to variability in the structure of both gray and white matter in sensory brain regions. We then delve into how brain activity (measured with task-based and resting-state functional imaging) in sensory regions informs our understanding of PTSD symptomology.

Sex differences in the effects of individual anxiety state on regional responses to negative emotional scenes

Background

Men and women are known to show differences in the incidence and clinical manifestations of mood and anxiety disorders. Many imaging studies have investigated the neural correlates of sex differences in emotion processing. However, it remains unclear how anxiety might impact emotion processing differently in men and women.

Method

We recruited 119 healthy adults and assessed their levels of anxiety using State-Trait Anxiety Inventory (STAI) State score. With functional magnetic resonance imaging (fMRI), we examined regional responses to negative vs. neutral (Neg-Neu) picture matching in the Hariri task. Behavioral data were analyzed using regression and repeated-measures analysis of covariance with age as a covariate, and fMRI data were analyzed using a full-factorial model with sex as a factor and age as a covariate.

Results

Men and women did not differ in STAI score, or accuracy rate or reaction time (RT) (Neg-Neu). However, STAI scores correlated positively with RT (Neg-Neu) in women but not in men. Additionally, in women, STAI score correlated positively with lingual gyrus (LG) and negatively with medial prefrontal cortex (mPFC) and superior frontal gyrus (SFG) activity during Neg vs. Neu trials. The parameter estimates (β's) of mPFC also correlated with RT (Neg-Neu) in women but not in men. Generalized psychophysiological interaction (gPPI) analysis in women revealed mPFC connectivity with the right inferior frontal gyrus, right SFG, and left parahippocampal gyrus during Neg vs. Neu trials in positive correlation with both STAI score and RT (Neg-Neu). In a mediation analysis, mPFC gPPI but not mPFC activity fully mediated the association between STAI scores and RT (Neg-Neu).

Conclusion

With anxiety affecting the behavioral and neural responses to negative emotions in women but not in men and considering the known roles of the mPFC in emotion regulation, we discussed heightened sensitivity and regulatory demands during negative emotion processing as neurobehavioral markers of anxiety in women.

Prior Sexual Trauma Exposure Impacts Posttraumatic Dysfunction and Neural Circuitry Following a Recent Traumatic Event in the AURORA Study

Background

Prior sexual trauma (ST) is associated with greater risk for posttraumatic stress disorder after a subsequent traumatic event; however, the underlying neurobiological mechanisms remain opaque. We investigated longitudinal posttraumatic dysfunction and amygdala functional dynamics following admission to an emergency department for new primarily nonsexual trauma in participants with and without previous ST.

Methods

Participants (N = 2178) were recruited following acute trauma exposure (primarily motor vehicle collision). A subset (n = 242) completed magnetic resonance imaging that included a fearful faces task and a resting-state scan 2 weeks after the trauma. We investigated associations between prior ST and several dimensions of posttraumatic symptoms over 6 months. We further assessed amygdala activation and connectivity differences between groups with or without prior ST.

Results

Prior ST was associated with greater posttraumatic depression (F1,1120 = 28.35, p = 1.22 × 10-7, ηp2 = 0.06), anxiety (F1,1113 = 17.43, p = 3.21 × 10-5, ηp2 = 0.05), and posttraumatic stress disorder (F1,1027 = 11.34, p = 7.85 × 10-4, ηp2 = 0.04) severity and more maladaptive beliefs about pain (F1,1113 = 8.51, p = .004, ηp2 = 0.02) but was not related to amygdala reactivity to fearful versus neutral faces (all ps > .05). A secondary analysis revealed an interaction between ST and lifetime trauma load on the left amygdala to visual cortex connectivity (peak Z value: -4.41, corrected p < .02).

Conclusions

Findings suggest that prior ST is associated with heightened posttraumatic dysfunction following a new trauma exposure but not increased amygdala activity. In addition, ST may interact with lifetime trauma load to alter neural circuitry in visual processing regions following acute trauma exposure. Further research should probe the relationship between trauma type and visual circuitry in the acute aftermath of trauma.

Heightened adolescent emotional reactivity in the brain is associated with lower future distress tolerance and higher depressive symptoms

Distress tolerance, the ability to persist while experiencing negative psychological states, is essential for regulating emotions and is a transdiagnostic risk/resiliency trait for multiple psychopathologies. Studying distress tolerance during adolescence, a period when emotion regulation is still developing, may help identify early risk and/or protective factors. This study included 40 participants (mean scan age = 17.5 years) and using an emotional Go-NoGo functional magnetic resonance imaging task and voxel-wise regression analysis, examined the association between brain response during emotional face processing and future distress tolerance (two ± 0.5 years), controlling for sex assigned at birth, age, and time between visits. Post-hoc analyses tested the mediating role of distress tolerance on the emotional reactivity and depressive symptom relationship. Whole-brain analysis showed greater inferior occipital gyrus activation was associated with less distress tolerance at follow-up. The mediating role of distress tolerance demonstrated a trend-level indirect effect. Findings suggest that individuals who allocate greater visual resources to emotionally salient information tend to exhibit greater challenges in tolerating distress. Distress tolerance may help to link emotional reactivity neurobiology to future depressive symptoms. Building distress tolerance through emotion regulation strategies may be an appropriate strategy for decreasing depressive symptoms.

Mood and anxiety disorders within the Research Domain Criteria framework of Positive and Negative Valence Systems: a scoping review

Introduction

While a growing body of research is adopting Research Domain Criteria (RDoC)-related methods and constructs, there is still a lack of comprehensive reviews on the state of published research on Positive Valence Systems (PVS) and Negative Valence Systems (NVS) in mood and anxiety disorders consistent with the RDoC framework.

Methods

Five electronic databases were searched to identify peer-reviewed publications covering research on "positive valence" and "negative valence" as well as "valence," "affect," and "emotion" for individuals with symptoms of mood and anxiety disorders. Data was extracted with a focus on disorder, domain, (sub-) constructs, units of analysis, key results, and study design. Findings are presented along four sections, distinguishing between primary articles and reviews each for PVS, NVS, and cross-domain PVS and NVS.

Results

A total of 231 abstracts were identified, and 43 met the inclusion criteria for this scoping review. Seventeen publications addressed research on PVS, seventeen on NVS, and nine covered cross-domain research on PVS and NVS. Psychological constructs were typically examined across different units of analysis, with the majority of publications incorporating two or more measures. Molecular, genetic, and physiological aspects were mainly investigated via review articles, primary articles focused on self-report, behavioral, and, to a lesser extent, physiological measures.

Conclusions

This present scoping review shows that mood and anxiety disorders were actively studied using a range of genetic, molecular, neuronal, physiological, behavioral, and self-report measures within the RDoC PVS and NVS. Results highlight the essential role of specific cortical frontal brain structures and of subcortical limbic structures in impaired emotional processing in mood and anxiety disorders. Findings also indicate overall limited research on NVS in bipolar disorders and PVS in anxiety disorders, a majority of self-report studies, and predominantly observational studies. Future research is needed to develop more RDoC-consistent advancements and intervention studies targeting neuroscience-driven PVS and NVS constructs.

A Neurobiological Profile Underlying Comorbidity Load and Prospective Increases in Dysphoria in a Focal Fear Sample

BACKGROUND

Knowledge of the neural mechanisms underlying increased disease burden in anxiety disorders that is unaccounted for by individual categorical diagnoses could lead to improved clinical care. Here, we tested the utility of a joint functional magnetic resonance imaging-electroencephalography neurobiological profile characterized by overvaluation of negative stimuli (amygdala) in combination with blunted elaborated processing of these same stimuli (the late positive potential [LPP], an event-related potential) in predicting increased psychopathology across a 2-year period in people with anxiety disorders.

METHODS

One hundred ten participants (64 female, 45 male, 1 other) including 78 participants with phobias who varied in the extent of their internalizing comorbidity and 32 participants who were free from psychopathology viewed negative and neutral pictures during separate functional magnetic resonance imaging blood oxygen level-dependent and electroencephalogram recordings. Dysphoria was assessed at baseline and 2 years later.

RESULTS

Participants with both heightened amygdala activation and blunted LPPs to negative pictures showed the greatest increases in dysphoria 2 years later. Cross-sectionally, participants with higher comorbidity load (≥2 additional diagnoses, n = 34) showed increased amygdala activation to negative pictures compared with participants with lower comorbidity load (≤1 additional diagnosis, n = 44) and compared with participants free from psychopathology. In addition, high comorbid participants showed reduced LPPs to negative pictures compared with low comorbid participants.

CONCLUSIONS

Heightened amygdala in response to negative stimuli in combination with blunted LPPs could indicate overvaluation of threatening stimuli in the absence of elaborated processing that might otherwise help regulate threat responding. This brain profile could underlie the worsening and maintenance of internalizing psychopathology over time.

Hippocampal and amygdala volumes vary with transdiagnostic psychopathological dimensions of distress, anxious arousal, and trauma

Reduced hippocampal and/or amygdala volumes have been reported in patients with a variety of different anxiety diagnoses, suggesting that structural alterations may vary transdiagnostically across the internalizing disorders. The current study measured hippocampal and amygdala volumes in anxiety and mood disorder patients assessing differences that vary dimensionally with transdiagnostic factors of distress, anxious arousal, and trauma, based on a principal components analysis of questionnaires relating to symptomology. High-resolution structural images were collected in a sample of 165 patients, and volumes extracted from the hippocampal formation (including CA1, CA2/3, CA4/DG, subiculum, and molecular layer) and the amygdala. Transdiagnostically, increasing distress was associated with reduced hippocampal CA1 volume, increasing anxious arousal was associated with reduced hippocampal CA4/DG volume, and increasing trauma severity was associated with reduced amygdala volume in women. Taken together, the data indicate that subcortical brain volumes decrease as the severity of transdiagnostic psychopathological symptomology increases.

Striatal reactivity during emotion and reward relates to approach-avoidance conflict behaviour and is altered in adults with anxiety or depression

BACKGROUND

We have previously reported activation in reward, salience and executive control regions during functional MRI (fMRI) using an approach-avoidance conflict (AAC) decision-making task with healthy adults. Further investigations into how anxiety and depressive disorders relate to differences in neural responses during AAC can inform their understanding and treatment. We tested the hypothesis that people with anxiety or depression have altered neural activation during AAC.

METHODS

We compared 118 treatment-seeking adults with anxiety or depression and 58 healthy adults using linear mixed-effects models to examine group-level differences in neural activation (fMRI) during AAC decision-making. Correlational analyses examined relationships between behavioural and neural measures.

RESULTS

Adults with anxiety or depression had greater striatal engagement when reacting to affective stimuli (p = 0.008, d = 0.31) regardless of valence, and weaker striatal engagement during reward feedback (p = 0.046, d = -0.27) regardless of the presence of monetary reward. They also had blunted amygdala activity during decision-making (p = 0.023, d = -0.32) regardless of the presence of conflict. Across groups, approach behaviour during conflict decision-making was inversely correlated with striatal activation during affective stimuli (p < 0.001, r = -0.28) and positively related to striatal activation during reward feedback (p < 0.001, r = 0.27).

LIMITATIONS

Our transdiagnostic approach did not allow for comparisons between specific anxiety disorders, and our cross-sectional approach did not allow for causal inference.

CONCLUSION

Anxiety and depression were associated with altered neural responses to AAC. Findings were consistent with the role of the striatum in action selection and reward responsivity, and they point toward striatal reactivity as a future treatment target. Blunting of amygdala activity in anxiety or depression may indicate a compensatory response to inhibit affective salience and maintain approach.

Developmental trauma: Conceptual framework, associated risks and comorbidities, and evaluation and treatment

Children exposed to adverse childhood experiences (ACEs) and pervasive interpersonal traumas may go on to develop PTSD and, in most cases, will further undergo a significant shift in their developmental trajectory. This paper examines contemporary research on Developmental Trauma (DT), which is inextricably linked to disruptions in social cognition, physiological and behavioral regulation, and parent-child attachments. Developmental trauma associated with early experiences of abuse or neglect leads to multi-faceted and longstanding consequences and underscores critical periods of development, complex stress-mediated adaptations, and multilevel, trans-theoretical influences in the diagnostic formulation and treatment of traumatized children, adolescents, and adults. Psychological and medical correlates of Developmental Trauma Disorder are considered, and directions for future research are discussed.

Revisiting the seven pillars of RDoC

BACKGROUND

In 2013, a few years after the launch of the National Institute of Mental Health's Research Domain Criteria (RDoC) initiative, Cuthbert and Insel published a paper titled "Toward the future of psychiatric diagnosis: the seven pillars of RDoC." The RDoC project is a translational research effort to encourage new ways of studying psychopathology through a focus on disruptions in normal functions (such as reward learning or attention) that are defined jointly by observable behavior and neurobiological measures. The paper outlined the principles of the RDoC research framework, including emphases on research that acquires data from multiple measurement classes to foster integrative analyses, adopts dimensional approaches, and employs novel methods for ascertaining participants and identifying valid subgroups.

DISCUSSION

To mark the first decade of the RDoC initiative, we revisit the seven pillars and highlight new research findings and updates to the framework that are related to each. This reappraisal emphasizes the flexible nature of the RDoC framework and its application in diverse areas of research, new findings related to the importance of developmental trajectories within and across neurobehavioral domains, and the value of computational approaches for clarifying complex multivariate relations among behavioral and neurobiological systems.

CONCLUSION

The seven pillars of RDoC have provided a foundation that has helped to guide a surge of new studies that have examined neurobehavioral domains related to mental disorders, in the service of informing future psychiatric nosology. Building on this footing, future areas of emphasis for the RDoC project will include studying central-peripheral interactions, developing novel approaches to phenotyping for genomic studies, and identifying new targets for clinical trial research to facilitate progress in precision psychiatry.

Vulnerable Dispositional Traits and Chronic Pain: Predisposing but not Predetermining

Dispositional traits can be protective or contribute to increased vulnerability in individuals with chronic pain. This study aims to evaluate the association between two dispositional trait measures, affect balance style and multi-domain trait groups, with psychosocial measures, clinical pain, functional pain, and experimental pain at two years in individuals with chronic knee pain. The study is a prospective analysis of 168 community dwelling individuals aged 45 to 85 years old with knee pain with or at risk for knee osteoarthritis. At baseline, affect balance style and multi-domain trait groups were associated with psychosocial measures, clinical pain, and functional status. At the two-year time point, the multi-domain trait groups were associated with the clinical pain measures. Interestingly, individuals with previously demonstrated vulnerable traits showed more variability in dispositional trait status at the two-year time point compared to those with dispositional traits previously demonstrated as more protective. Findings reiterate that dispositional traits are predisposing but are not predetermining regarding pain-related experiences. PERSPECTIVE: Vulnerable and protective dispositional traits are positively and negatively associated with clinical pain and functional limitations respectively. Although considered relatively stable, a 30-50% shift in dispositional traits was indicated over a two-year period. Findings highlight that dispositional trait are modifiable and thus, predisposing but not predetermining for persisting chronic pain.

fMRI replicability during emotional scene viewing: Functional regions and sample size

Recent findings have questioned the replicability of functional magnetic resonance imaging (fMRI) in the study of affective processing, reporting low replicability of emotional enhancement during a face-matching task. However, poor replicability may instead reflect a lack of emotional engagement for face matching. In the current study, replicability of emotional enhancement was tested in a large (N = 160) sample when emotional engagement was assessed during pleasant, neutral, and unpleasant picture viewing, which reliably engages affective reactions in both the brain and the body. Replicability was computed using a subsampling technique, in which random sets of subjects of different sample sizes (N = 20, 40, 60, 80) were selected from the entire dataset, and replicability of emotional enhancement for peaks, clusters, and voxels were averaged across 500 permutations for each sample size. Consistent with previous findings, fMRI replicability increased with increasing sample size. On the other hand, even with relatively small samples, fMRI replicability for peaks, clusters, and voxels during emotional, compared to neutral, scene viewing was good to excellent. Importantly, replicability varied in different brain regions, with excellent replicability at both the cluster and peak level with an N of 40, at the most conservative threshold (p < .001), in the amygdala and the visual cortex. The data argue against general recommendations regarding sample size in fMRI studies of emotion, suggesting instead that degree of replicability depends on successful emotional engagement in task-related brain regions.

Psychophysiological predictors of change in emotion dysregulation 6 months after traumatic injury

Emotion dysregulation that occurs after trauma conveys risk for multiple disorders, including posttraumatic stress disorder, depression, and anxiety. Psychophysiological data (e.g., skin conductance level [SCL]) may be a useful biomarker for quantifying emotion dysregulation given that autonomic nervous system (ANS)-mediated arousal may underlie this feature. In this longitudinal study, we tested whether SCL collected following a single-incident traumatic injury could predict changes in emotion dysregulation over 6 months. Sixty-six adults were recruited from the emergency department; SCL was quantified during an active trauma narrative, in which participants re-told their traumatic event to a research staff member, as well as a neutral narrative for a control condition. Change in SCL (ΔSCL) was calculated using a maximum activation - minimum activation difference score. Multilevel linear modeling was used to test ΔSCL as a predictor of emotion dysregulation using the Emotion Dysregulation Scale (EDS) over time (3 timepoints over 6 months). Results showed that greater ΔSCL - indicative of increasing arousal- during both the trauma (p = 0.037) and neutral (p = 0.013) narratives was a significant predictor of greater emotion dysregulation at each subsequent timepoint. Further, we found a ΔSCL by time interaction, such that less ΔSCL during the neutral narrative predicted decreased emotion dysregulation over time (b = -1.26, SE = 0.43, t = -2.91, p = 0.004). Results validate the use of lab-based assessments of arousal to study emotion dysregulation in trauma survivors. That recovery from emotion dysregulation was predicted by less arousal during a neutral event underscores the importance of clinically targeting response to safety in trauma survivors.

Childhood Maltreatment Influences Autonomic Regulation and Mental Health in College Students

Childhood maltreatment history may influence autonomic reactivity and recovery to stressors. Hypothetically, the maltreatment history may contribute to a retuned autonomic nervous system that is reflected in a novel metric, vagal efficiency (VE), designed to assess the functional efficiency of vagal cardioinhibitory pathways on heart rate. We explored whether VE mediates the well-documented relationship between maltreatment history and psychiatric symptoms. We also investigated the relationship between measures of autonomic regulation in response to the physical and emotional challenges and psychiatric symptoms. Participants (n = 167) completed self-report measures of psychiatric symptoms and had continuous beat-to-beat heart rate monitored before, during, and after physical and emotional stressors. Participants with maltreatment histories exhibited lower VE, which mediated the association of maltreatment history and the psychiatric symptoms of anxiety and depression. Consistent with prior literature, there were significant associations between maltreatment history and autonomic reactivity (i.e., heart rate and respiratory sinus arrhythmia) during emotional and physical challenges; however, when VE was entered as a covariate these associations were no longer statistically significant. Blunted VE may reflect a neural pathway through which maltreatment retunes autonomic regulation and provides a neurophysiological platform that increases mental health risk.

Morally Distressing Experiences, Moral Injury, and Burnout in Florida Healthcare Providers during the COVID-19 Pandemic

Because healthcare providers may be experiencing moral injury (MI), we inquired about their healthcare morally distressing experiences (HMDEs), MI perpetrated by self (Self MI) or others (Others MI), and burnout during the COVID-19 pandemic. Participants were 265 healthcare providers in North Central Florida (81.9% female, M_age = 37.62) recruited via flyers and emailed brochures that completed online surveys monthly for four months. Logistic regression analyses investigated whether MI was associated with specific HMDEs, risk factors (demographic characteristics, prior mental/medical health adversity, COVID-19 protection concern, health worry, and work impact), protective factors (personal resilience and leadership support), and psychiatric symptomatology (depression, anxiety, and PTSD). Linear regression analyses explored how Self/Others MI, psychiatric symptomatology, and the risk/protective factors related to burnout. We found consistently high rates of MI and burnout, and that both Self and Others MI were associated with specific HMDEs, COVID-19 work impact, COVID-19 protection concern, and leadership support. Others MI was also related to prior adversity, nurse role, COVID-19 health worry, and COVID-19 diagnosis. Predictors of burnout included Self MI, depression symptoms, COVID-19 work impact, and leadership support. Hospital administrators/supervisors should recognize the importance of supporting the HCPs they supervise, particularly those at greatest risk of MI and burnout.

Sex differences in the aging brain? A voxel-based morphometry analysis of the hippocampus and the amygdala

OBJECTIVES

Volumetric reductions in the hippocampus and the amygdala are considered a hallmark for many psychiatric and neurodegenerative disorders. Because brain atrophy is often observed in disorders that have a higher prevalence in females than males, it has been proposed that sex differences in the aging brain represent a vulnerability factor for developing more severe psychiatric conditions.

METHODS

Sexual dimorphism was assessed in the amygdala volume and hippocampal volume in a large sample (N = 554) of healthy individuals ranging from 20 to 79 years old, using structural brain data available from a public dataset.

RESULTS

In both the hippocampus and the amygdala, a quadratic association was found between age and brain volume. Using uncorrected data for head size [total intracranial volume (TIV)], males clearly demonstrated larger amygdala and hippocampal volume across all ages, and an interaction between age and sex in the hippocampus supported the hypothesis of accelerated atrophy in the hippocampus in later life (60-79 years old). However, when volumetric data adjusted for TIV were used, sex differences were not observed in the hippocampus nor the amygdala.

CONCLUSION

These findings support the extensive series of studies suggesting that sex differences in brain volume are likely related to the confounding effect of head size. While continued effort is allocated to identify sex-related biomarkers, increasing evidence suggests that sexual dimorphism in the hippocampus or the amygdala does not appear to be the primary candidates for precision medicine to identify sex-related biomarkers that index potential vulnerabilities.

What's in a Face? Amygdalar Sensitivity to an Emotional Threatening Faces Task and Transdiagnostic Internalizing Disorder Symptoms in Participants Receiving Attention Bias Modification Training

Background

Altered amygdala activation in response to the emotional matching faces (EMF) task, a task thought to reflect implicit emotion detection and reactivity, has been found in some patients with internalizing disorders; mixed findings from the EMF suggest individual differences (within and/or across diagnoses) that may be important to consider. Attention Bias Modification (ABM), a mechanistic attention-targeting intervention, has demonstrated efficacy in treatment of internalizing disorders. Individual differences in neural activation to a relatively attention-independent task, such as the EMF, could reveal novel neural substrates relevant in ABM's transdiagnostic effects, such as the brain's generalized threat reactivity capacity.

Methods

In a sample of clinically anxious patients randomized to ABM (n = 43) or sham training (n = 18), we measured fMRI activation patterns during the EMF and related them to measures of transdiagnostic internalizing symptoms (i.e., anxious arousal, general distress, anhedonic depression, and general depressive symptoms).

Results

Lower baseline right amygdala activation to negative (fearful/angry) faces, relative to shapes, predicted greater pre-to-post reduction in general depression symptoms in ABM-randomized patients. Greater increases in bilateral amygdalae activation from pre-to-post ABM were associated with greater reductions in general distress, anhedonic depression, and general depression symptoms.

Conclusions

ABM may lead to greater improvement in depressive symptoms in individuals exhibiting blunted baseline amygdalar responses to the EMF task, potentially by enhancing neural-level discrimination between negative and unambiguously neutral stimuli. Convergently, longitudinal increases in amygdala reactivity from pre-to-post-ABM may be associated with greater improvement in depression, possibly secondary to improved neural discrimination of threat and/or decreased neurophysiological threat avoidance in these specific patients.

Global Psychotrauma Screen (GPS): psychometric properties in two Internet-based studies

Background: Potentially traumatic stressors can lead to various transdiagnostic outcomes beyond PTSD alone but no brief screening tools exist for measuring posttraumatic responses in a transdiagnostic manner. Objective: Assess the psychometric characteristics of a new 22-item transdiagnostic screening measure, the Global Psychotrauma Screen (GPS). Method: An internet survey was administered with English speaking participants recruited passively via the website of the Global Collaboration on Traumatic Stress (GC-TS) (nGC-TS  = 1,268) and actively via Amazon's MTurk (nMTurk  = 1,378). Exploratory factor analysis, correlational analysis, sensitivity and specificity analysis, and comparisons in response between the two samples and between male and female respondents were conducted. Results: Exploratory factor analysis revealed a single factor underlying symptom endorsements in both samples, suggesting that such problems may form a unitary transdiagnostic, posttraumatic outcome. Convergent validity of the GPS symptom and risk factors was established with measures of PTSD and dissociative symptoms in the MTurk sample. Gender differences were seen primarily at the item level with women more often endorsing several symptoms and specific risk factors in the MTurk sample, and the GC-TS recruited sample endorsed more symptoms and risk factors than the MTurk sample, suggesting that the GPS may be sensitive to group differences. A GPS symptom cut-off score of 8 identified optimized sensitivity and specificity relative to probable PTSD based on PCL-5 scores. Conclusions: The current results provide preliminary support for the validity of the GPS as a screener for the concurrent measurement of several transdiagnostic outcomes of potentially traumatic stressors and the apparent unifactorial structure of such symptoms is suggestive of a single or unitary posttraumatic outcome. Future research is needed to evaluate whether similarly strong psychometric properties can be yielded in response to completion of the GPS in other languages.

Trauma-related dysfunction in the fronto-striatal reward circuit

INTRODUCTION

Reduced reactivity to pleasurable stimulation is a defining symptom of post-traumatic stress disorder (PTSD), but trauma exposure also increases the severity of many anxiety and mood disorders, including depression, social anxiety, and panic disorder, suggesting that reward system dysfunction might be pervasive in the internalizing disorders. The ventromedial prefrontal cortex (vmPFC) and ventral striatum are core components of the reward circuit and the current study assesses functional activity and connectivity in this circuit during emotional picture viewing in anxiety and mood disorder patients.

METHOD

Functional brain activity (fMRI) and functional connectivity in the fronto-striatal circuit were measured in a large sample of patients diagnosed with anxiety and mood disorders (n=155) during affective scene viewing as it varied with trauma exposure and temperament.

RESULTS

In women, but not men, blunted fronto-striatal connectivity was associated with increased posttraumatic anhedonic symptoms, whereas the amplitude of functional activity was not related to trauma exposure. In both men and women, reduced fronto-striatal connectivity was associated with decreases in temperamental positive affect. When predicting fronto-striatal connectivity, temperament and posttraumatic symptomology accounted for independent proportions of variance.

LIMITATIONS

In this civilian sample of anxiety disorder patients, men reported very little trauma-related symptomology.

CONCLUSIONS

Because dysfunctional reward processing due to trauma and temperament is pervasive across the internalizing disorder spectrum, assessing the integrity of the fronto-striatal reward circuit could provide important information in diagnostic and treatment protocols.

fMRI evidence reveals emotional biases in bilingual decision making

Research indicates that the foreign language effect on decision making can be partially explained by a reduction in emotional response in the second language. In this fMRI study, we aimed at elucidating the neural mechanisms underpinning the interaction between language and emotion in decision making. Across multiple trials, Chinese-English bilinguals were asked to decide whether to gamble in a Gambling task, and received feedbacks either in L1 (Chinese) or in L2 (English). If they gambled, feedbacks were either positively or negatively valenced words; if they did not gamble, feedback was the word 'safe'. We assessed how emotionally valenced words were processed in the two languages, and how this processing influenced subsequent decision making. Overall, we found evidence that in L2 context, but not in L1 context, loss aversion was mediated by the dorsolateral prefrontal cortex (dlPFC) which also showed strong functional connectivity with the visual cortex, suggesting an avoidance mechanism for negative stimuli in L2. However, we also found an enhanced response to positive feedbacks in L2 compared to L1, as evidenced by greater activation of the hippocampus for win feedbacks compared to safe feedbacks in L2, eventually resulting in a greater tendency to gamble. Thus, foreign language influenced decision making by both regulating emotional response to negative stimuli and enhancing emotional response to positive stimuli. This study helps unveiling the neural bases of the interaction between language and emotion in the foreign language context.

Resilience, pain, and the brain: Relationships differ by sociodemographics

Chronic musculoskeletal (MSK) pain is disabling to individuals and burdensome to society. A relationship between telomere length and resilience was reported in individuals with consideration for chronic pain intensity. While chronic pain associates with brain changes, little is known regarding the neurobiological interface of resilience. In a group of individuals with chronic MSK pain, we examined the relationships between a previously investigated resilience index, clinical pain and functioning measures, and pain-related brain structures, with consideration for sex and ethnicity/race. A cross-sectional analysis of 166 non-Hispanic Black and non-Hispanic White adults, 45-85 years of age with pain ≥ 1 body site (s) over the past 3 months was completed. Measures of clinical pain and functioning, biobehavioral and psychosocial resilience, and structural MRI were completed. Our findings indicate higher levels of resilience associate with lower levels of clinical pain and functional limitations. Significant associations between resilience, ethnicity/race, and/or sex, and pain-related brain gray matter structure were demonstrated in the right amygdaloid complex, bilateral thalamus, and postcentral gyrus. Our findings provide compelling evidence that in order to decipher the neurobiological code of chronic pain and related protective factors, it will be important to improve how chronic pain is phenotyped; to include an equal representation of females in studies including analyses stratifying by sex, and to consider other sociodemographic factors.

Trauma Affects Prospective Relationships Between Reward-Related Ventral Striatal and Amygdala Activation and 1-Year Future Hypo/Mania Trajectories

BACKGROUND

Trauma exposure is associated with a more severe, persistent course of affective and anxiety symptoms. Markers of reward neural circuitry function, specifically activation to reward prediction error (RPE), are impacted by trauma and predict the future course of affective symptoms. This study's purpose was to determine how lifetime trauma exposure influences relationships between reward neural circuitry function and the course of future affective and anxiety symptoms in a naturalistic, transdiagnostic observational context.

METHODS

A total of 59 young adults aged 18-25 (48 female and 11 male participants, mean ± SD = 21.5 ± 2.0 years) experiencing psychological distress completed the study. Participants were evaluated at baseline, 6, and 12 months. At baseline, the participants reported lifetime trauma events and completed a monetary reward functional magnetic resonance imaging task. Affective and anxiety symptoms were reported at each visit, and trajectories were calculated using MPlus. Neural activation during RPE and other phases of reward processing were determined using SPM8. Trauma and reward neural activation were entered as predictors of symptom trajectories.

RESULTS

Trauma exposure moderated prospective relationships between left ventral striatum (β = -1.29, p = .02) and right amygdala (β = 0.58, p = .04) activation to RPE and future hypo/mania severity trajectory: the interaction between greater trauma and greater left ventral striatum activation to RPE was associated with a shallower increase in hypo/mania severity, whereas the interaction between greater trauma and greater right amygdala activation to RPE was associated with increasing hypo/mania severity.

CONCLUSIONS

Trauma exposure affects prospective relationships between markers of reward circuitry function and affective symptom trajectories. Evaluating trauma exposure is thus crucial in naturalistic and treatment studies aiming to identify neural predictors of future affective symptom course.

Negative content enhances stimulus-specific cerebral activity during free viewing of pictures, faces, and words

Negative visual stimuli have been found to elicit stronger brain activation than do neutral stimuli. Such emotion effects have been shown for pictures, faces, and words alike, but the literature suggests stimulus-specific differences regarding locus and lateralization of the activity. In the current functional magnetic resonance imaging study, we directly compared brain responses to passively viewed negative and neutral pictures of complex scenes, faces, and words (nouns) in 43 healthy participants (21 males) varying in age and demographic background. Both negative pictures and faces activated the extrastriate visual cortices of both hemispheres more strongly than neutral ones, but effects were larger and extended more dorsally for pictures, whereas negative faces additionally activated the superior temporal sulci. Negative words differentially activated typical higher-level language processing areas such as the left inferior frontal and angular gyrus. There were small emotion effects in the amygdala for faces and words, which were both lateralized to the left hemisphere. Although pictures elicited overall the strongest amygdala activity, amygdala response to negative pictures was not significantly stronger than to neutral ones. Across stimulus types, emotion effects converged in the left anterior insula. No gender effects were apparent, but age had a small, stimulus-specific impact on emotion processing. Our study specifies similarities and differences in effects of negative emotional content on the processing of different types of stimuli, indicating that brain response to negative stimuli is specifically enhanced in areas involved in processing of the respective stimulus type in general and converges across stimuli in the left anterior insula.

Aversive perception in a threat context: Separate and independent neural activation

Unpleasant, compared to neutral, scenes reliably prompt enhanced functional brain activity in the amygdala and inferotemporal cortex. Considering data from psychophysiological studies in which defensive reactivity is further enhanced when viewing unpleasant scenes under threat of shock (compared to safety), the current study investigates functional activation in the amygdala-inferotemporal circuit when unpleasant (or neutral) scenes are viewed under threat of shock or safety. In this paradigm, a cue signaling threat or safety was presented in conjunction with either an unpleasant or neutral picture. Replicating previous studies, unpleasant, compared to neutral, scenes reliably enhanced activation in the amygdala and inferotemporal cortex. Functional activity in these regions, however, did not differ whether scenes were presented in a context threatening shock exposure, compared to safety, which instead activated regions of the anterior insula and cingulate cortex. Taken together, the data support a view in which neural regions activated in different defensive situations act independently.

Modeling neuroaffective biomarkers of drug addiction: A Bayesian nonparametric approach using dirichlet process mixtures

BACKGROUND

The properties of neurophysiological processes related to addiction have received much attention in the literature. However, empirical evidence of meaningful and useful characterization of these processes is limited. Recent studies have found that electrophysiological responses to emotional and drug-related cues can be used to create profiles that reliably predict smoking relapse.

NEW METHOD

This paper evaluates the validity of classifying electrophysiological responses into distinct profiles using a Bayesian dirichlet process mixture (DPM) model. The DPM is a Bayesian nonparametric (BNP) method to modeling unknown number of profiles characterized by uncertainty in cluster membership and in cluster number.

RESULTS

The DPM model confirmed previously identified neuroaffective reactivity profiles, but also revealed a finer level of granularity in the clustering. Specifically, in addition to the two clusters previously identified in the literature, the BNP methods identified a cluster of individuals showing similar responses to smoking, pleasant, neutral and unpleasant cues.

COMPARISON WITH EXISTING METHODS

BNP models provide an alternative to the k-mean clustering approach to modeling EEG-based neuroaffective profiles. Unlike k-means clustering, BNP models compute the probability that a subject belongs to a cluster while taking into consideration uncertainty in the number of clusters.

CONCLUSIONS

Our results confirm the reliability of the two clusters previously identified in these data, but also provide new insights by revealing a cluster that presented similar responses to stimuli with different contents. This finding may be related to the uncertainty in classification or overlapping brain-reactivity profiles.

Common circuit or paradigm shift? The functional brain in emotional scene perception and emotional imagery

Meta-analytic and experimental studies investigating the neural basis of emotion often compare functional activation in different emotional induction contexts, assessing evidence for a "core affect" or "salience" network. Meta-analyses necessarily aggregate effects across diverse paradigms and different samples, which ignore potential neural differences specific to the method of affect induction. Data from repeated measures designs are few, reporting contradictory results with a small N. In the current study, functional brain activity is assessed in a large (N = 61) group of healthy participants during two common emotion inductions-scene perception and narrative imagery-to evaluate cross-paradigm consistency. Results indicate that limbic and paralimbic regions, together with visual and parietal cortex, are reliably engaged during emotional scene perception. For emotional imagery, in contrast, enhanced functional activity is found in several cerebellar regions, hippocampus, caudate, and dorsomedial prefrontal cortex, consistent with the conception that imagery is an action disposition. Taken together, the data suggest that a common emotion network is not engaged across paradigms, but that the specific neural regions activated during emotional processing can vary significantly with the context of the emotional induction.