Early Life Stress and Trauma and Enhanced Limbic Activation to Emotionally Valenced Faces in Depressed and Healthy Children

Abstract

Objective Previous studies have examined the relationships between structural brain characteristics and early life stress in adults. However, there is limited evidence for functional brain variation associated with early life stress in children. We hypothesized that early life stress and trauma would be associated with increased functional brain activation to negative emotional faces in children with and without a history of depression. Method Psychiatric diagnosis and life events in children (starting at ages 3–5) were assessed in a longitudinal study. A follow-up magnetic resonance imaging (MRI) study acquired data (N = 115 at ages 7–12, 51% female) on functional brain response to fearful, sad, and happy faces relative to neutral faces. We used a region of interest (ROI) mask within cortico-limbic areas and conducted regression analyses and repeated-measures analysis of covariance (ANCOVA). Results Greater activations to fearful, sad, and happy faces in the amygdala and its neighboring regions were found in children with higher life stress. Moreover, an association between life stress and left hippocampal and globus pallidus activity depended on children's diagnostic status. Finally, all children with higher life trauma showed greater bilateral amygdala and cingulate activity specific to sad faces, but not the other emotional faces, although right amygdala activity was moderated by psychiatric status. Conclusions These findings may suggest that limbic hyperactivity is a biomarker of early life stress and trauma in children and may have implications in the risk trajectory for depression and other stress-related disorders. However, this pattern varied based on emotion type and history of psychopathology.

State of the Art Review: Poverty and the Developing Brain

“…20,37,[40][41][42] Functional studies are most consistent; lower childhood SES and risky family environments are associated with greater or less-regulated amygdala activation during emotion processing tasks. 47,49,51,52 Chronic stress appears to be a factor in the relationship between childhood poverty and amygdala activity, 47 and studies have highlighted the role of parent functioning. For example, threats to the parent-child bond, including maternal depression and insecure infant attachment, have been associated with larger amygdalae in childhood and young adulthood, 48,50 as well as higher amygdalahippocampal volume ratios, a risk factor for emotional dysregulation.…”

“…22,37,55,56 Evidence is accumulating that these structural changes help explain the relationship between poverty, chronic stress, and cognitive and behavioral outcomes. 39,43,[46][47][48][49][50][51][52][55][56][57][58] For example, younger adolescents exposed to high cumulative life stress during childhood have been shown to demonstrate poorer executive functioning related to smaller PFC volumes. 56 Similarly, 1 longitudinal study found that the relationship between early-life poverty and conduct disorder symptoms later in life was mediated by volume reductions in the orbitofrontal cortex.…”

On antidepressants and still feeling low

“…However, these short-term benefits are proposed to be associated with long-term functional and structural changes of limbic-related brain regions-perhaps most notably in the amygdala-that manifest as a function of the severity of the ELS exposure (1,9,27,36,37). Consistent with this framework, in childhood, the severity of ELS exposure has been positively associated with amygdala reactivity to both threatening and happy faces in a dose-dependent manner (26,38). Similarly, as adults, the severity of prior stress exposure has also been associated with amygdala engagement in response to threatening faces (19).…”

“…Mechanisms by which ELS affects adult psychopathology are thought to involve-at least in part-engagement of the HPA axis in the immediate response to the stressor (2,6,10,11,19,26). This engagement of the HPA axis and release of stress-related hormones are, in turn, believed to cause structural and functional changes in the neural circuits that underlie emotion processing.…”

The complex neurobiology of resilient functioning after child maltreatment

“…McCrory, De Brito, & Viding, 2011;E. J. McCrory et al, 2013;Olsavsky et al, 2013;Suzuki et al, 2014;N Tottenham et al, 2011;Van Harmelen et al, 2013) and altered striatal reward processing (Boecker et al, 2014;Dillon et al, 2009;Hanson, Hariri, & Williamson, 2015;Holz et al, 2016;Philip et al, 2016). Furthermore, CM has been associated with altered activity in, as well as functional connectivity between, PFC regions associated with stress response and emotion regulation (Bruce et al, 2013;Gregory A. Fonzo, Huemer, & Etkin, 2016;Jankowski et al, 2016;Lim et al, 2015;Mueller et al, 2010;Vanessa B Puetz et al, 2014;S J A van der Werff et al, 2012;van Harmelen, Hauber, et al, 2014;van Harmelen, van Tol, et al, 2014).…”