There is a relative consensus about the detrimental impact of childhood maltreatment on mental health and behavioral problems later in life, including aggression behavior. Prior research suggests that this association may, in part, be explained by neurophysiological stress mechanisms designed to support adaptation to changing environments. Moreover, very little is known on the reasons why individuals from the general population aggress others in comparison to those who do not (e.g., dating violence, bullying, public shootings, road rage, and violent encounters with strangers). To this end, we invited 160 participants to come to our laboratory, of which 60 had reported having been maltreated as children, whereas the remaining participants did not. A wide range of neurophysiological measures was measured in the context of a laboratory-based stress paradigm and in response to provocation, including the stress hormone cortisol, cardiac measures, testosterone and DNA methylation (i.e., modifications in the chemistry of the DNA that have the potential to alter genetic expression without changing the DNA sequence).
In a paper recently accepted in Development and Psychopathology, we reported that maltreated participants had higher cortisol responses to stress in comparison to controls, but this association was more complex than previously thought. Indeed, a shift from lower-to-higher cortisol responses was noted as the severity of maltreatment experiences increased, providing further empirical support for the idea that persistent dysregulation of the cortisol response to stress may arise in the context of past exposure to maltreatment.
These findings invite practitioners to consider coping strategies and stress regulation as potential targets for preventing or reducing mental health and behavioral difficulties.
Our research team has also brought light on findings suggesting a synergic effect between maltreatment and cortisol response to stress, whereby these early adverse experiences were associated with more depressive symptoms, aggression, and anger rumination in adulthood among participants with moderate-to-higher cortisol response to stress.
Conversely, childhood maltreatment was not associated with these negative outcomes for those who exhibited a lower pattern of reactivity. Also, being interested to generate knowledge that could be mobilized to support the well-being of individuals who were maltreated during childhood, we offered preliminary evidence suggesting that maltreatment was associated with a more frequent use of emotion-oriented coping strategies (e.g., become very frustrated when faced with difficult situations), although the opposite was found for task-oriented coping strategies (e.g., trying to change their behavior to solve the problem). Importantly, these strategies have generally been hypothesized to signal more and less mental health and behavioral difficulties, respectively. Altogether, these findings invite practitioners to consider coping strategies and stress regulation as potential targets for preventing or reducing mental health and behavioral difficulties, including aggression, among young male adults with a history of childhood maltreatment.
Ouellet-Morin I, Robitaille MP, Langevin S, Cantave C, Brendgen M, & Lupien S. (accepted). Enduring effect of childhood maltreatment on cortisol and heart rate responses to stress: The moderating role of severity of experiences. Development and Psychopathology.