> However, a more novel observation from this study was that there appeared to be two developmental stages when trauma exposure was associated with elevated levels of subsequent psychopathology. First, participants exposed to child maltreatment during early childhood (ages 0–5) had both depression and PTSD symptoms that were up to twice as high as those exposed during later developmental stages. These effects were detected even after controlling for sociodemographic characteristics, exposure to other types of traumas, and the number of occurrences of child maltreatment (i.e., the frequency of exposure). Such findings are consistent with several prospective 15–17 and retrospective studies 18,31 also showing an elevated risk for subsequent depression, in particular, among those first exposed in the first five years of life. Although the mechanisms linking early trauma exposure to subsequent psychopathology risk are not well known 56, early trauma exposure may be more damaging than later trauma exposure because it compromises a child’s ability to successfully master stage-salient developmental tasks (e.g., self-regulation, secure attachments) 57 and damages the foundation of brain architecture and neurobiological systems involved in regulating arousal, emotion, stress responses, and reward processing 58–61, which are all implicated in the onset and persistence of stress-related disorders like depression and PTSD.

> Second, we also found that participants first exposed during middle childhood (ages 6–10) to other types of interpersonal violence, including witnessing a friend or family member being murdered or being attacked with or without a weapon, had depressive symptoms scores that were about twice as high as those first exposed during adulthood. Similar results were also detected for PTSD, but were not statistically significant after adjusting the frequency or number of occurrences of child exposure. These results are consistent with at least some prior studies suggesting that trauma during middle childhood, including severe illness 41, or natural disasters 34–36 is associated with an elevated risk for PTSD relative to exposure in other periods. Although the mechanisms driving this association are unclear, exposure to interpersonal violence events during middle childhood may be more harmful than exposure in adulthood for a number of reasons: school-age children may be in a unique developmental stages where they do not benefit as much from parental buffering 62, when demands from the social environment increase (i.e., relating to peers, participating in school activities) 63, and when adaptive coping capacities are still developing 64.

Guess I'll die...