While both frontal lobe and HPA axis dysfunction are largely influential in regard to criminal behavior, for this discussion I’ve chosen to focus on the HPA axis. According to Jambroes et al. (2019), the HPA axis, or the Hypothalamic-Pituitary-Adrenal axis is the one of the main stress regulating systems in the body. The functioning of this system is closely linked to flight or fight responses as it helps to control the release of cortisol. Cortisol is relevant as reduced levels of it have been linked to increased instances of persistent and aggressive behavior in youth (Jambroes et al., 2019). Additionally, the HPA-axis is associated with a myriad of criminal behaviors, to include callous-unemotional (CU) traits, and others associated with antisocial personality disorder (ASPD). As explained by Jambroes et al. (2019), ASPD is linked to low levels of arousal, which are in turn made evident by a decrease in HPA-axis activity. As a whole, the concept o
f reduced HPA-axis activity leading to antisocial tendencies can be referred to as the fearlessness theory, suggesting that individuals with these deficits do not experience fear in the same way as their healthy counterparts. (Jambroes et al., 2019). Further expanding on that is the fact that fearless behavior has a tendency to predispose youth to aggressive and delinquent behaviors as they are not deterred by consequences or punishments. Pompa (2006) echoes these findings, indicating how low HPA-axis activity is connected to antisocial behavior and other negative outcomes, such as social isolation and unemployment. Response to treatment (or lack thereof) in individuals with HPA-axis dysfunction also helps to offer some insight into the long-term deficits of having this dysfunction. Specifically, Jambroes et al. (2019) advises that those with this dysfunction are typically unresponsive to treatment, resulting in the continuation of criminal behavior.