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.

Neighborhood Disadvantage and Neural Correlates of Threat and Reward Processing in Survivors of Recent Trauma.

Importance: Differences in neighborhood socioeconomic characteristics are important considerations in understanding differences in risk vs resilience in mental health. Neighborhood disadvantage is associated with alterations in the function and structure of threat neurocircuitry. Objective: To investigate associations of neighborhood disadvantage with white and gray matter and neural reactivity to positive and negative stimuli in the context of trauma exposure. Design, Setting, and Participants: In this cross-sectional study, survivors of trauma who completed sociodemographic and posttraumatic symptom assessments and neuroimaging were recruited as part of the Advancing Understanding of Recovery After Trauma (AURORA) study between September 2017 and June 2021. Data analysis was performed from October 25, 2022, to February 15, 2023. Exposure: Neighborhood disadvantage was measured with the Area Deprivation Index (ADI) for each participant home address. Main Outcomes and Measures: Participants completed separate threat and reward tasks during functional magnetic resonance imaging. Diffusion-weighted and high-resolution structural images were also collected. Linear models assessed the association of ADI with reactivity, microstructure, and macrostructure of a priori regions of interest after adjusting for income, lifetime trauma, sex at birth, and age. A moderated-mediation model tested whether ADI was associated with neural activity via microstructural changes and if this was modulated by PTSD symptoms. Results: A total of 280 participants (183 females [65.4%]; mean [SD] age, 35.39 [13.29] years) completed the threat task and 244 participants (156 females [63.9%]; mean [SD] age, 35.10 [13.26] years) completed the reward task. Higher ADI (per 1-unit increase) was associated with greater insula (t274 = 3.20; ß = 0.20; corrected P = .008) and anterior cingulate cortex (ACC; t274 = 2.56; ß = 0.16; corrected P = .04) threat-related activity after considering covariates, but ADI was not associated with reward reactivity. Greater disadvantage was also associated with altered microstructure of the cingulum bundle (t274 = 3.48; ß = 0.21; corrected P = .001) and gray matter morphology of the ACC (cortical thickness: t273 = -2.29; ß = -0.13; corrected P = .02; surface area: t273 = 2.53; ß = 0.13; corrected P = .02). The moderated-mediation model revealed that ADI was associated with ACC threat reactivity via cingulum microstructural changes (index of moderated mediation = -0.02). However, this mediation was only present in individuals with greater PTSD symptom severity (at the mean: ß = -0.17; standard error = 0.06, t= -2.28; P = .007; at 1 SD above the mean: ß = -0.28; standard error = 0.08; t = -3.35; P < .001). Conclusions and Relevance: In this study, neighborhood disadvantage was associated with neurobiology that supports threat processing, revealing associations of neighborhood disadvantage with neural susceptibility for PTSD and suggesting how altered structure-function associations may complicate symptoms. Future work should investigate specific components of neighborhood disadvantage that may be associated with these outcomes.

Structural inequities contribute to racial/ethnic differences in neurophysiological tone, but not threat reactivity, after trauma exposure.

Considerable racial/ethnic disparities persist in exposure to life stressors and socioeconomic resources that can directly affect threat neurocircuitry, particularly the amygdala, that partially mediates susceptibility to adverse posttraumatic outcomes. Limited work to date, however, has investigated potential racial/ethnic variability in amygdala reactivity or connectivity that may in turn be related to outcomes such as post-traumatic stress disorder (PTSD). Participants from the AURORA study (n = 283), a multisite longitudinal study of trauma outcomes, completed functional magnetic resonance imaging and psychophysiology within approximately two-weeks of trauma exposure. Seed-based amygdala connectivity and amygdala reactivity during passive viewing of fearful and neutral faces were assessed during fMRI. Physiological activity was assessed during Pavlovian threat conditioning. Participants also reported the severity of posttraumatic symptoms 3 and 6 months after trauma. Black individuals showed lower baseline skin conductance levels and startle compared to White individuals, but no differences were observed in physiological reactions to threat. Further, Hispanic and Black participants showed greater amygdala connectivity to regions including the dorsolateral prefrontal cortex (PFC), dorsal anterior cingulate cortex, insula, and cerebellum compared to White participants. No differences were observed in amygdala reactivity to threat. Amygdala connectivity was associated with 3-month PTSD symptoms, but the associations differed by racial/ethnic group and were partly driven by group differences in structural inequities. The present findings suggest variability in tonic neurophysiological arousal in the early aftermath of trauma between racial/ethnic groups, driven by structural inequality, impacts neural processes that mediate susceptibility to later PTSD symptoms.

Distinctive impacts of sexual trauma versus non-sexual trauma on PTSD profiles in highly trauma-exposed, Black women.

BACKGROUND: Prior findings suggest that psychopathology following interpersonal trauma or assaultive violence may present differently from prototypical posttraumatic stress disorder (PTSD). However, whether this is true for sexual trauma (ST) in the context of other salient lifetime traumatic experiences is yet unknown. We predicted that ST exposure may result in higher avoidance and numbing symptoms and blunted fear responses, relative to non-sexual trauma (NST), particularly if ST occurred during childhood. METHODS: Participants were n = 5163 Black women recruited in an urban public hospital. We investigated effects of ST on PTSD symptoms, fear-potentiated startle (FPS) response (n = 285), and amygdala reactivity and habituation to social threat cues with fMRI (n = 95). RESULTS: ST was associated with greater PTSD symptoms (p = 2.64 × 10-21), but this was observed across all symptom clusters. Women who experienced repeated ST in both childhood and adulthood showed greater PTSD (p = .0009) and numbing symptoms (p = .002). In the FPS paradigm, the ST group startled more on all blocks and stimulus types than the NST group (p = .004). Developmental timing of ST did not influence startle magnitude. ST was not associated with amygdala habituation or reactivity. LIMITATIONS: Generalizability is limited to Black women with a high trauma burden. Associations are cross-sectional, limiting causal conclusions. CONCLUSION: While survivors of ST may present with more severe PTSD symptoms, their profiles are not characteristically different from similar NST controls. Childhood sexual abuse exposure alone did not result in a unique symptom profile. ST represents a uniquely high-burden stressor with likelihood for more severe posttraumatic outcomes.