Procedure
Participants were recruited from the community through various forms of advertisements (e.g., television, bus ads, flyers, and newspapers). Upon arrival to the laboratory, parents provided consent and children provided assent. Following this, children completed the morphed face task and parents completed questionnaires including a report of their current address. All study procedures were approved by the university’s Institutional Review Board.

Results

Preliminary analyses revealed that children from racial/ethnic minority groups lived in areas with greater crime risk (M = 93.54,SD = 28.62) than their non-Hispanic White peers (M = 68.64, SD = 34.75), t (91) = 3.57, p < .01, Cohen’s d = .79. This said, there was a clear range of crime risk for minority children (58-143) and non-Hispanic White children (13-143). To test our hypotheses regarding the link between neighborhood crime and children’s LPP responses to emotional stimuli, and how this may be moderated by children’s race/ethnicity, we used a repeated measures general linear model with level of neighborhood crime and racial-ethnic group (non-Hispanic White vs. racial-ethnic minority) as between subjects factors and emotion (fearful, sad, happy) and morph level (low, medium, high) as within subjects factors. In this analysis, there were significant crime × emotion × morph, F (4, 384) = 5.03, p < .001, ηp2 = .05, and racial/ethnic group × emotion × morph, F (4, 384) = 4.66,p = .001, ηp2 = .05, interactions. Importantly, the crime × racial/ethnic group × emotion × morph interaction was also significant, F (4, 384) = 3.70,p = .006, ηp2 = .04.
To determine the form of this interaction, we examined the crime × emotion × morph interaction separately in minority and non-Hispanic White children. In these analyses, the crime × emotion × morph interaction was significant for racial/ethnic minority children,F (4, 132) = 4.89, p = .001,ηp2 = .13, but not for non-Hispanic White children, F (4, 252) = 1.36, p = .25,ηp2 = .02. Examining this further in children from racial/ethnic minority groups, the crime × emotion interaction was significant for fearful faces, F (2, 66) = 6.99, p = .002, ηp2 = .18, but not for happy, F (2, 66) = 2.66, p = .08,ηp2 = .08, or sad, F(2, 66) = 0.73, p = .48, ηp2 = .02, faces. As a final step, we examined the correlation between neighborhood crime and LPP amplitude to fearful faces at each morph level in racial/ethnic minority children. Higher levels of neighborhood crime were associated with greater LPP amplitude for fearful faces at high, r = .36, p = .03, but not medium, r = -.14,p = .42, or low, r = -.26, p = .13, morph levels. Although all analyses were based on continuous levels of neighborhood crime risk, we used a median split to provide a visual depiction of these results (see Figure 1).
To evaluate the robustness of these results, we conducted follow-up partial correlation analyses to determine whether the relation between higher levels of neighborhood crime risk and greater LPP responses to fearful faces among racial/ethnic minority children was maintained after statistically controlling for the influence of children’s family income and their current symptoms of anxiety and depression. In call cases, the significant relation was maintained (all p s < .05).

Conclusions

The goal of this study was to examine the link between census-derived indices of neighborhood crime risk and children’s neural reactivity to threat-relevant stimuli, and whether this link may be stronger among children from racial/ethnic minority backgrounds. We found that levels of higher neighborhood crime risk were associated with larger LPP amplitudes to threat-relevant images, but only among racial/ethnic minority children and not among non-Hispanic White children. This finding was specific to full intensity threat images and was not observed at lower intensities. It was also specific to threat-relevant images (fearful faces) and was not observed for non-threat negative images (sad face) or positive images (happy faces). Therefore, in addition to living in areas characterized by higher crime risk, children from racial/ethnic minority groups were also more reactive to the presence of higher crime risk in terms of their neural reactivity. This suggests that levels of neighborhood crime risk may be more salient in racial/ethnic minority children than for non-Hispanic White children. Importantly, the relation between neighborhood crime risk and children’s LPP reactivity to threat-relevant images was also maintained when we statistically controlled for the influence of children’s family income and current symptoms of depression and anxiety, suggesting that the relation is at least partially independent of these other factors.
The current results build upon previous research showing that direct experiences with crime and violence are associated with greater neural reactivity to threat-relevant stimuli, which suggests that similar patterns are observed as a function of simply living in an area characterized by higher risk of crime (King et. al., 2022). For example, previous research has shown that living in an area with higher crime rates, regardless of whether the individual is a victim of crime themselves, is associated with higher levels of externalizing problems and anxiety symptoms (Hessel et. al., 2019; Jacobs et. al., 2019; Lowe et. al., 2016; Ramey and Harrington, 2019). Research has also shown that this risk differs across racial/ethnic groups such that racial/ethnic minorities that resided in areas experiencing higher crime rates are at particularly high risk for developing psychopathology (Andrews et. al., 2019). The current results suggest that increased neural reactivity to threat may be one mechanism by which living in an area characterized by higher risk of crime increases risk for psychopathology among racial/ethnic minority children. However, longitudinal studies are needed to more formally test this mediational hypothesis.
Despite the strengths of this study, there were limitations as well, which highlight important areas for future research. First, the current study was cross sectional and longitudinal studies are needed to determine if neighborhood characteristics contribute to increased neural reactivity to threat-relevant stimuli over time. These longitudinal studies should also examine the impact of moving into versus out of higher-crime areas on children’s neural reactivity to threat, including potential sensitive periods, given evidence from previous research that moving out of high crime areas is associated with reductions in anxiety and depression (King et. al., 2022). A second limitation is that representation for individuals of different racial/ethnic minority groups was limited, so we could not examine whether the link between neighborhood crime risk and neural reactivity to threat is stronger for some minority groups than others. Finally, additional research is needed to understand the mechanisms underlying the link between neighborhood crime risk and neural reactivity to threat among racial/ethnic minority children. Although, on average, racial/ethnic minority families in this sample tended to live in areas with higher crime rates than the non-Hispanic White families, level of neighborhood crime risk also appear to be more salient to children from minority backgrounds. Although the specific mechanisms for this are not clear, it is possible that children from racial/ethnic minority backgrounds have a greater fear of being a victim themselves or may be more reactive to the correlates of living in a higher crime area (e.g., increased police presence). Future research is needed to explore these possibilities.
In summary, this study supports the link between neighborhood crime risk and children’s increased neural reactivity to threat-relevant stimuli, but only among racial/ethnic minority children and not non-Hispanic White children. This increased neural reactivity to threat may be one mechanism of risk for later psychopathology in these children. Future research is needed to identify potential sensitivity periods for the impact of neighborhood characteristics as well as the impact of moving out of higher crime areas. Research is also needed to better understand mediators and moderators of the link between neighborhood crime risk and minority children’s neural reactivity to threat, which may highlight additional targets of intervention to reduce risk for later psychopathology in these children.