Which of the following is not a system of increased arousal in post-traumatic stress disorder?

In the context of post-traumatic stress disorder (PTSD), the concept of increased arousal is associated with several identifiable symptoms. The heightened startle response, emotional numbing, and hypervigilance are recognized systems of increased arousal that reflect how individuals with PTSD respond to trauma cues.

Heightened startle response involves an exaggerated reaction to sudden stimuli, signifying heightened alertness and sensitivity to potential threats. Emotional numbing can also manifest in PTSD as a response to overwhelming feelings, leading individuals to disconnect emotionally, which is indicative of an altered state of arousal. Hypervigilance is a state of being excessively alert or watchful for signs of danger, tightly correlated to the persistent feelings of anxiety and fear experienced by those with PTSD.

Ambivalence towards danger, on the other hand, does not fit into the established patterns of increased arousal associated with PTSD. Rather than reflecting a heightened response to threats, it suggests uncertainty or mixed feelings, which does not directly pertain to the hyper-arousal symptoms typically observed in individuals suffering from PTSD. Thus, ambivalence towards danger more accurately represents a psychological state apart from the hyper-arousal symptoms that define the disorder's response mechanisms.