Association of Racial Discrimination With Neural Response to Threat in Black Women in the US Exposed to Trauma

Abstract

Importance: Racial discrimination has a clear impact on health-related outcomes, but little is known about how discriminatory experiences are associated with neural response patterns to emotionally salient cues, which likely mediates these outcomes.

Objective: To examine associations of discriminatory experiences with brainwide response to threat-relevant cues in trauma-exposed US Black women as they engage in an attentionally demanding task.

Design, setting, and participants: A cross-sectional study was conducted from May 1, 2014, to July 1, 2019, among 55 trauma-exposed US Black women to examine associations of racial discrimination experiences with patterns of neural response and behavior to trauma-relevant images in an affective attentional control task. Posttraumatic stress disorder (PTSD) symptoms and trauma exposure were entered as covariates to isolate variance associated with experiences of racial discrimination.

Exposures: Varying levels of trauma, PTSD symptoms, and experiences of racial discrimination.

Main outcomes and measures: Experiences of Discrimination Questionnaire (EOD) (range, 0-9) for count of the number of situations for which each participant reported having unfair treatment for a racial reason. Experiences of trauma and PTSD symptoms were assessed with the Traumatic Events Inventory (TEI) (number of times the person was exposed to trauma; score range, 0-112) and PTSD Symptom Scale (PSS) (score range, 0-51). Response to trauma-relevant vs neutral distractor cues were assessed via functional magnetic resonance imaging during performance of an affective Stroop (attentional control) task. Statistical analyses were conducted at a whole-brain, voxelwise level with familywise error correction.

Results: In this study of 55 Black women in the US (mean [SD] age, 37.7 [10.7] years; range, 21-61 years), participants reported a mean (SD) TEI frequency of 33.0 (18.8) and showed moderate levels of current PTSD symptoms (mean [SD] PSS score, 15.4 [12.9]). Mean (SD) EOD scores were 2.35 (2.44) and were moderately correlated with current PTSD symptoms (PSS total: r = 0.36; P=.009) but not with age (r = 0.20; P = .15) or TEI frequency (r = -0.02; P = .89). During attention to trauma-relevant vs neutral images, more experiences of racial discrimination were associated with significantly greater response in nodes of emotion regulation and fear inhibition (ventromedial prefrontal cortex) and visual attention (middle occipital cortex) networks, even after accounting for trauma and severity of PTSD symptoms (brainwide familywise error corrected; r = 0.33 for ventromedial prefrontal cortex; P = .02). Racial discrimination was also associated with affective Stroop task performance; errors on trials with threat-relevant stimuli were negatively correlated with experiences of racial discrimination (r = -0.41; P = .003).

Conclusions and relevance: These findings suggest that experiences of racial discrimination associate with disproportionately greater response in brain regions associated with emotion regulation and fear inhibition and visual attention. Frequent racism experienced by Black individuals may potentiate attentional and regulatory responses to trauma-relevant stressors and lead to heightened modulation of regulatory resources. This may represent an important neurobiological pathway for race-related health disparities.

Figure 1.. Associations of Racial Discrimination With Neural Response During Attention to Threat-Relevant Affective Stroop Trials (Posttraumatic Stress Disorder Symptoms Covaried)

A, Brainwide correlation between racial discrimination (Experiences of Discrimination Questionnaire [EOD] total) and response to threat-relevant vs neutral affective Stroop trials. B, Increased activation in the ventromedial prefrontal cortex (vmPFC, circled in orange) to threat-relevant vs neutral trials corresponds with more experiences of racial discrimination, seen in the correlation plot (r = 0.33; P = .02). The diagonal line in the plot indicates the line of best fit. BOLD indicates blood oxygen level–dependent.

Figure 2.. Association of Experiences of Racial Discrimination With Affective Stroop Performance on Threat-Relevant Trials (Posttraumatic Stress Disorder Symptoms Covaried)

Percentage errors on affective Stroop threat-relevant trials negatively correlated with racial discrimination experiences, seen in the partial correlation plot of residuals (r = −0.41; P = .003). The diagonal line in the plot indicates the line of best fit. EOD indicates Experiences of Discrimination Questionnaire.