Threat bias and resting state functional connectivity of the amygdala and bed nucleus stria terminalis

Childhood Maltreatment and Amygdala-Mediated Anxiety and Posttraumatic Stress Following Adult Trauma

Background

Childhood abuse (physical, emotional, and sexual) is associated with aberrant connectivity of the amygdala, a key threat-processing region. Heightened amygdala activity also predicts adult anxiety and posttraumatic stress disorder (PTSD) symptoms, as do experiences of childhood abuse. The current study explored whether amygdala resting-state functional connectivity may explain the relationship between childhood abuse and anxiety and PTSD symptoms following trauma exposure in adults.

Methods

Two weeks posttrauma, adult trauma survivors (n = 152, mean age [SD] = 32.61 [10.35] years; women = 57.2%) completed the Childhood Trauma Questionnaire and underwent resting-state functional magnetic resonance imaging. PTSD and anxiety symptoms were assessed 6 months posttrauma. Seed-to-voxel analyses evaluated the association between childhood abuse and amygdala resting-state functional connectivity. A mediation model evaluated the potential mediating role of amygdala connectivity in the relationship between childhood abuse and posttrauma anxiety and PTSD.

Results

Childhood abuse was associated with increased amygdala connectivity with the precuneus while covarying for age, gender, childhood neglect, and baseline PTSD symptoms. Amygdala-precuneus resting-state functional connectivity was a significant mediator of the effect of childhood abuse on anxiety symptoms 6 months posttrauma (B = 0.065; 95% CI, 0.013-0.130; SE = 0.030), but not PTSD. A secondary mediation analysis investigating depression as an outcome was not significant.

Conclusions

Amygdala-precuneus connectivity may be an underlying neural mechanism by which childhood abuse increases risk for anxiety following adult trauma. Specifically, this heightened connectivity may reflect attentional vigilance for threat or a tendency toward negative self-referential thoughts. Findings suggest that childhood abuse may contribute to longstanding upregulation of attentional vigilance circuits, which makes one vulnerable to anxiety-related symptoms in adulthood.

Data-driven, connectome-wide analysis identifies psychosis-specific brain correlates of fear and anxiety

Decades of psychosis research highlight the prevalence and the clinical significance of negative emotions, such as fear and anxiety. Translational evidence demonstrates the pivotal role of the amygdala in fear and anxiety. However, most of these approaches have used hypothesis-driven analyses with predefined regions of interest. A data-driven analysis may provide a complimentary, unbiased approach to identifying brain correlates of fear and anxiety. The aim of the current study was to identify the brain basis of fear and anxiety in early psychosis and controls using a data-driven approach. We analyzed data from the Human Connectome Project for Early Psychosis, a multi-site study of 125 people with psychosis and 58 controls with resting-state fMRI and clinical characterization. Multivariate pattern analysis of whole-connectome data was used to identify shared and psychosis-specific brain correlates of fear and anxiety using the NIH Toolbox Fear-Affect and Fear-Somatic Arousal scales. We then examined clinical correlations of Fear-Affect scores and connectivity patterns. Individuals with psychosis had higher levels of Fear-Affect scores than controls (p < 0.05). The data-driven analysis identified a cluster encompassing the amygdala and hippocampus where connectivity was correlated with Fear-Affect score (p < 0.005) in the entire sample. The strongest correlate of Fear-Affect was between this cluster and the anterior insula and stronger connectivity was associated with higher Fear-Affect scores (r = 0.31, p = 0.0003). The multivariate pattern analysis also identified a psychosis-specific correlate of Fear-Affect score between the amygdala/hippocampus cluster and a cluster in the ventromedial prefrontal cortex (VMPFC). Higher Fear-Affect scores were correlated with stronger amygdala/hippocampal-VMPFC connectivity in the early psychosis group (r = 0.33, p = 0.002), but not in controls (r = -0.15, p = 0.28). The current study provides evidence for the transdiagnostic role of the amygdala, hippocampus, and anterior insula in the neural basis of fear and anxiety and suggests a psychosis-specific relationship between fear and anxiety symptoms and amygdala/hippocampal-VMPFC connectivity. Our novel data-driven approach identifies novel, psychosis-specific treatment targets for fear and anxiety symptoms and provides complimentary evidence to decades of hypothesis-driven approaches examining the brain basis of threat processing.

Sex differences in the effects of trait anxiety and age on resting-state functional connectivities of the amygdala

Background

Numerous studies characterized how resting-state functional connectivities (rsFCs) of the amygdala were disrupted in emotional disorders and varied with emotional traits, including anxiety. With trait anxiety known to diminish with age, a critical issue concerns disambiguating the effects of age and anxiety on amygdala rsFCs in studying the neural bases of individual differences in anxiety.

Methods

Two-hundred adults (83 women) 19-85 years of age underwent fMRI and assessment for trait anxiety. Amygdala rsFC correlates were identified using multiple regression with age and anxiety in the same model for all and separately in men and women. The rsFC correlates were examined for age-anxiety interaction.

Results

Anxiety was negatively correlated with amygdala-temporooccipital gyri rsFC in all and in men alone. In women, amgydala rsFC with the thalamus/pallidum, angular/supramarginal gyri, inferior temporal gyrus, and posterior insula correlated positively and rsFC with calcarine cortex and caudate correlated negatively with anxiety. We also observed sex differences in age correlation of amgydala-posterior cingulate cortex/precuneus and -insula/temporoparietal rsFCs, with stronger associations in women. In women alone, anxiety and age interacted to determine amygdala rsFC with the thalamus/pallidum, calcarine cortex, and caudate, with older age associated with stronger correlation between anxiety and the rsFCs.

Limitations

The findings need to be validated in an independent sample and further explored using task-based data.

Conclusion

Highlighting anxiety- and age- specific as well as interacting correlates of amygdala rsFCs and sex differences in the correlates, the findings may shed light on the neural markers of anxiety.

Assessment of Functional and Dysfunctional Perceived Threat of Hate Crimes Among Persons With and Without Disability

This study examined the relationship between disability status and perceived threat of hate crimes. Building on existing conceptual frameworks, first we differentiated between dysfunctional perceived threat that damages quality of life and functional perceived threat that has the capacity to be motivational and precautionary. We then examined how disability status predicts individuals' threat memberships across dysfunctional and functional perceived threats of hate crimes. Results-based on a survey of 1,824 adults recruited from Amazon's Mechanical Turk-indicate that persons with a disability are more likely than those without a disability to exhibit dysfunctional perceived threat (vs. functional or no perceived threat) of hate crime across different bias motivations. This relationship was evident even when accounting for those most at risk for each type of hate crime (e.g., persons of color for anti-race/ethnicity hate crime). Further, persons with cognitive and physical disabilities were associated with higher odds of dysfunctional perceived threat of all types of hate crimes when compared to persons without a disability. Overall, the present study highlights that persons with a disability may experience exacerbated consequences of subjective threat of hate crimes. Findings also suggest the importance of an intersectional approach to hate crime by considering how disability may intersect with other forms of oppression in relation to perceived threat of hate crime. Implications and future directions, especially as they relate to measurement, are discussed.

A systematic review and meta-analysis of resting-state fMRI in anxiety disorders: Need for data sharing to move the field forward

Anxiety disorders are among the most prevalent psychiatric disorders. Neuroimaging findings remain uncertain, and resting state functional magnetic resonance (rs-fMRI) connectivity is of particular interest since it is a scalable functional imaging modality. Given heterogeneous past findings for rs-fMRI in anxious individuals, we characterize patterns across anxiety disorders by conducting a systematic review and meta-analysis. Studies were included if they contained at the time of scanning both a healthy group and a patient group. Due to insufficient study numbers, the quantitative meta-analysis only included seed-based studies. We performed an activation likelihood estimation (ALE) analysis that compared patients and healthy volunteers. All analyses were corrected for family-wise error with a cluster-level threshold of p < .05. Patients exhibited hypo-connectivity between the amygdala and the medial frontal gyrus, anterior cingulate cortex, and cingulate gyrus. This finding, however, was not robust to potential file-drawer effects. Though limited by strict inclusion criteria, our results highlight the heterogeneous nature of reported findings. This underscores the need for data sharing when attempting to detect reliable patterns of disruption in brain activity across anxiety disorders.

Sleep dysfunction mediates the relationship between hypothalamic-insula connectivity and anxiety-depression symptom severity bidirectionally in young adults

BACKGROUND

The hypothalamus plays a crucial role in regulating sleep-wake cycle and motivated behavior. Sleep disturbance is associated with impairment in cognitive and affective functions. However, how hypothalamic dysfunction may contribute to inter-related sleep, cognitive, and emotional deficits remain unclear.

METHODS

We curated the Human Connectome Project dataset and investigated how hypothalamic resting state functional connectivities (rsFC) were associated with sleep dysfunction, as evaluated by the Pittsburgh Sleep Quality Index (PSQI), cognitive performance, and subjective mood states in 687 young adults (342 women). Imaging data were processed with published routines and evaluated with a corrected threshold. We examined the inter-relationship amongst hypothalamic rsFC, PSQI score, and clinical measures with mediation analyses.

RESULTS

In whole-brain regressions with age and drinking severity as covariates, men showed higher hypothalamic rsFC with the right insula in correlation with PSQI score. No clusters were identified in women at the same threshold. Both hypothalamic-insula rsFC and PSQI score were significantly correlated with anxiety and depression scores in men. Further, mediation analyses showed that PSQI score mediated the relationship between hypothalamic-insula rsFC and anxiety/depression symptom severity bidirectionally in men.

CONCLUSIONS

Sleep dysfunction is associated with negative emotions and hypothalamic rsFC with the right insula, a core structure of the interoceptive circuits. Notably, anxiety-depression symptom severity and altered hypothalamic-insula rsFC are related bidirectionally by poor sleep quality. These findings are specific to men, suggesting potential sex differences in the neural circuits regulating sleep and emotional states that need to be further investigated.

Alterations in BNST Intrinsic Functional Connectivity in Early Abstinence from Alcohol Use Disorder

AIMS

Maintaining abstinence from alcohol use disorder (AUD) is extremely challenging, partially due to increased symptoms of anxiety and stress that trigger relapse. Rodent models of AUD have identified that the bed nucleus of the stria terminalis (BNST) contributes to symptoms of anxiety-like behavior and drug-seeking during abstinence. In humans, however, the BNST's role in abstinence remains poorly understood. The aims of this study were to assess BNST network intrinsic functional connectivity in individuals during abstinence from AUD compared to healthy controls and examine associations between BNST intrinsic functional connectivity, anxiety and alcohol use severity during abstinence.

METHODS

The study included resting state fMRI scans from participants aged 21-40 years: 20 participants with AUD in abstinence and 20 healthy controls. Analyses were restricted to five pre-selected brain regions with known BNST structural connections. Linear mixed models were used to test for group differences, with sex as a fixed factor given previously shown sex differences.

RESULTS

BNST-hypothalamus intrinsic connectivity was lower in the abstinent group relative to the control group. There were also pronounced sex differences in both the group and individual analyses; many of the findings were specific to men. Within the abstinent group, anxiety was positively associated with BNST-amygdala and BNST-hypothalamus connectivity, and men, not women, showed a negative relationship between alcohol use severity and BNST-hypothalamus connectivity.

CONCLUSIONS

Understanding differences in connectivity during abstinence may help explain the clinically observed anxiety and depression symptoms during abstinence and may inform the development of individualized treatments.

Aberrant functional connectivity of the bed nucleus of the stria terminalis and its age dependence in children and adolescents with social anxiety disorder

BACKGROUND

Social anxiety disorder (SAD) is a prevalent and impairing mental disorder among children and adolescents. The bed nucleus of the stria terminalis (BNST) plays a critical role in anxiety disorders, including valence surveillance and hypervigilance for potential threats. However, the role of BNST and its related functional network in children and adolescents with SAD has not been fully investigated. This study examined the aberration of BNST's functional connectivity and its age dependence in adolescents with SAD.

METHODS

Using a sample of 75 SAD patients and 75 healthy controls (HCs) children aged 9-18 years old, we delineated the group-by-age interaction of BNST-seeded functional connectivity (FC) during resting state and movie-watching. The relationships between BNST-seeded FC and clinical scores were also examined.

RESULTS

During movie viewing, the FC between the right BNST and the left amygdala, bilateral posterior cingulate cortex (PCC), bilateral superior temporal cortex, and right pericalcarine cortex showed a diagnostic group-by-age interaction. Compared to HCs, SAD patients showed a significant enhancement of the above FC at younger ages. Meanwhile, they showed an age-dependent decrease in FC between the right BNST and left amygdala. Furthermore, for SAD patients, FC between the right BNST and left amygdala during movie viewing was positively correlated with separation anxiety scores.

CONCLUSIONS

The right BNST plays an essential role in the aberrant brain functioning in children and adolescents with SAD. The atypicality of BNST's FC has remarkable age dependence in SAD, suggesting an association of SAD with neurodevelopmental traits.

Altered metabolic connectivity between the amygdala and default mode network is related to pain perception in patients with cancer

We investigated the neural correlates for chronic cancer pain conditions by retrospectively analyzing whole brain regions on 18F-fluoro-2-deoxyglucose-positron emission tomography images acquired from 80 patients with head and neck squamous cell carcinoma and esophageal cancer. The patients were divided into three groups according to perceived pain severity and type of analgesic treatment, namely patients not under analgesic treatment because of no or minor pain, patients with good pain control under analgesic treatment, and patients with poor pain control despite analgesic treatment. Uncontrollable cancer pain enhanced the activity of the hippocampus, amygdala, inferior temporal gyrus, and temporal pole. Metabolic connectivity analysis further showed that amygdala co-activation with the hippocampus was reduced in the group with poor pain control and preserved in the groups with no or minor pain and good pain control. The increased although imbalanced activity of the medial temporal regions may represent poor pain control in patients with cancer. The number of patients who used anxiolytics was higher in the group with poor pain control, whereas the usage rates were comparable between the other two groups. Therefore, further studies should investigate the relationship between psychological conditions and pain in patients with cancer and analyze the resultant brain activity.Trial registration: This study was registered at clinicaltrials.gov on 9/3/20 (NCT04537845).

Racial Discrimination and Resting-State Functional Connectivity of Salience Network Nodes in Trauma-Exposed Black Adults in the United States

Importance

For Black US residents, experiences of racial discrimination are still pervasive and frequent. Recent empirical work has amplified the lived experiences and narratives of Black people and further documented the detrimental effects of racial discrimination on both mental and physical health; however, there is still a need for further research to uncover the mechanisms connecting experiences of racial discrimination with adverse health outcomes.

Objective

To examine neurobiological mechanisms that may offer novel insight into the association of racial discrimination with adverse health outcomes.

Design, Setting, and Participants

This cross-sectional study included 102 Black adults who had recently experienced a traumatic injury. In the acute aftermath of the trauma, participants underwent a resting-state functional magnetic resonance imaging scan. Individuals were recruited from the emergency department at a Midwestern level 1 trauma center in the United States between March 2016 and July 2020. Data were analyzed from February to May 2021.

Exposures

Self-reported lifetime exposure to racial discrimination, lifetime trauma exposure, annual household income, and current posttraumatic stress disorder (PTSD) symptoms were evaluated.

Main Outcomes and Measures

Seed-to-voxel analyses were conducted to examine the association of racial discrimination with connectivity of salience network nodes (ie, amygdala and anterior insula).

Results

A total of 102 individuals were included, with a mean (SD) age of 33 (10) years and 58 (57%) women. After adjusting for acute PTSD symptoms, annual household income, and lifetime trauma exposure, greater connectivity between the amygdala and thalamus was associated with greater exposure to discrimination (t(97) = 6.05; false discovery rate (FDR)-corrected P = .03). Similarly, racial discrimination was associated with greater connectivity between the insula and precuneus (t(97) = 4.32; FDR-corrected P = .02).

Conclusions and Relevance

These results add to the mounting literature that racial discrimination is associated with neural correlates of vigilance and hyperarousal. The study findings extend this theory by showing that this association is apparent even when accounting for socioeconomic position, lifetime trauma, and symptoms of psychological distress related to an acute trauma.

Corticotropin-releasing factor neurons in the bed nucleus of the stria terminalis exhibit sex-specific pain encoding in mice

The bed nucleus of the stria terminalis (BNST) plays an emerging role in pain regulation. Pharmacological studies have found that inhibiting corticotropin-releasing factor (CRF) signaling in the BNST can selectively mitigate the sensory and affective-motivational components of pain. However, mechanistic insight on the source of CRF that drives BNST responses to these harmful experiences remains unknown. In the present study, we used a series of genetic approaches to show that CRF in the BNST is engaged in the processing and modulation of pain. We conducted cell-type specific in vivo calcium imaging in CRF-Cre mice and found robust and synchronized recruitment of BNSTCRF neurons during acute exposures to noxious heat. Distinct patterns of recruitment were observed by sex, as the magnitude and timing of heat responsive activity in BNSTCRF neurons differed for male and female mice. We then used a viral approach in Floxed-CRF mice to selectively reduce CRF expression in the BNST and found it decreased nociceptive sensitivity for both sexes and increased paw attending for females. Together, these findings reveal that CRF in the BNST influences multiple facets of the pain experience to impact the sex-specific expression of pain-related behaviors.

Between Action and Emotional Survival During the COVID-19 era: Sensorimotor Pathways as Control Systems of Transdiagnostic Anxiety-Related Intolerance to Uncertainty

Objectives: The COVID-19 pandemic and aligned social and physical distancing regulations increase the sense of uncertainty, intensifying the risk for psychopathology globally. Anxiety disorders are associated with intolerance to uncertainty. In this review we describe brain circuits and sensorimotor pathways involved in human reactions to uncertainty. We present the healthy mode of coping with uncertainty and discuss deviations from this mode. Methods: Literature search of PubMed and Google Scholar. Results: As manifestation of anxiety disorders includes peripheral reactions and negative cognitions, we suggest an integrative model of threat cognitions modulated by sensorimotor regions: "The Sensorimotor-Cognitive-Integration-Circuit." The model emphasizes autonomic nervous system coupling with the cortex, addressing peripheral anxious reactions to uncertainty, pathways connecting cortical regions and cost-reward evaluation circuits to sensorimotor regions, filtered by the amygdala and basal ganglia. Of special interest are the ascending and descending tracts for sensory-motor crosstalk in healthy and pathological conditions. We include arguments regarding uncertainty in anxiety reactions to the pandemic and derive from our model treatment suggestions which are supported by scientific evidence. Our model is based on systematic control theories and emphasizes the role of goal conflict regulation in health and pathology. We also address anxiety reactions as a spectrum ranging from healthy to pathological coping with uncertainty, and present this spectrum as a transdiagnostic entity in accordance with recent claims and models. Conclusions: The human need for controllability and predictability suggests that anxiety disorders reactive to the pandemic's uncertainties reflect pathological disorganization of top-down bottom-up signaling and neural noise resulting from non-pathological human needs for coherence in life.

Abnormal Functional Connectivity of the Amygdala in Mild Cognitive Impairment Patients With Depression Symptoms Revealed by Resting-State fMRI

Convergent evidence indicates that individuals with symptoms of depression exhibit altered functional connectivity (FC) of the amygdala, which is a key brain region in processing emotions. At present, the characteristics of amygdala functional circuits in patients with mild cognitive impairment (MCI) with and without depression are not clear. The current study examined the features of amygdala FC in patients with MCI with depression symptoms (D-MCI) using resting-state functional magnetic resonance imaging. We acquired resting-state functional magnetic resonance imaging data from 16 patients with D-MCI, 18 patients with MCI with no depression (nD-MCI), and 20 healthy controls (HCs) using a 3T scanner and compared the strength of amygdala FC between the three groups. Patients with D-MCI exhibited significant FC differences in the amygdala-medial prefrontal cortex and amygdala-sensorimotor networks. These results suggest that the dysfunction of the amygdala-medial prefrontal cortex network and the amygdala-sensorimotor network might be involved in the neural mechanism underlying depression in MCI.

Neural Responses to Reward in a Gambling Task: Sex Differences and Individual Variation in Reward-Driven Impulsivity

Previous work suggests sex differences in reward sensitivity. However, it remains unclear how men and women differ in the neural processes of reward-driven impulsivity. With a data set of 968 subjects (502 women) curated from the Human Connectome Project, we investigated sex differences in regional activations to reward and to punishment in a gambling task. Individual variations in reward-driven impulsivity were quantified by the difference in reaction time between reward and punishment blocks in the gambling task, as well as by a behavioral measure of delay discounting. At a corrected threshold, men and women exhibited significant differences in regional activations to reward and to punishment. Longer reaction times during reward versus punishment blocks, indicative of more cautious responding, were associated with left-hemispheric lateral prefrontal cortical activation to reward in men but not women. Steeper discounting was associated with higher activation to reward in the right-hemispheric dorsal anterior cingulate cortex and angular gyrus in women but not men. These sex differences were confirmed in slope tests. Together, the results highlight the sex-specific neural processes of reward-driven impulsivity with left-hemispheric prefrontal cortex supporting impulse control in men and right-hemispheric saliency circuit playing a more important role in diminished impulse control in women.