How does response to psychological trauma work?
The trauma response is activated when the brain’s limbic system registers an experience like those listed above as a threat to safety, or when we learn about or witness these events happening to others, particularly those to whom we are closely connected. This threat appraisal activates the fear response, also referred to as the sympathetic nervous system (SNS) or fight/flight/freeze. The fear response mobilizes our defenses to try to safely manage the threat, including releasing adrenaline into the body, raising the heart rate, and withdrawing energy from bodily processes that are not essential to survival in the moment (such as digestion). If the perceived threat turns out not be a danger, or if we can fight or flee from it and return to external safety, activation of the parasympathetic nervous system (PNS) helps us to eventually return to an internal place of calm. In these circumstances we may be able to “shake off” the frightening experiencing and make our way back to homeostasis.
When the circumstances are such that fight or flight is not a viable option or not enough to overcome the danger of the threat, or if we have entered a frozen/immobilized state (which usually happens without conscious awareness or intent), we are likely to remain in a prolonged state of SNS activation, affecting memory consolidation, emotional expression and regulation, thought processes, concentration, sleep, appetite, and blood pressure, among other reactions. At this point, the body has moved from the fear response to the trauma response. This does not necessarily mean that someone will enter a prolonged state of psychological trauma (or develop symptoms that eventually meet the diagnostic criteria for Posttraumatic Stress Disorder or other mental health disorders that can develop in response to trauma). It does, however, mean that it is harder to access the calming effects of the PNS. A midshipman whose SNS is in a prolonged state of activation may appear on edge, irritable, and easily startled, though they may also appear numb, lethargic, and zoned out. Often people experience changes in sleep and appetite patterns, difficulty concentrating, and racing thoughts.While distinct experiences that trigger the trauma response may lead to a prolonged state of psychological trauma, generally it is the before, during, and aftermath of the traumatic event that determines the impact and duration of a psychological trauma state and accompanying symptomatology. For example, high levels of social support before and after a trauma often mitigate symptoms and can increase speed of recovery. Low support or experiences of victim blaming after a trauma, such as when rape victims are asked what they were wearing or doing to incite the perpetrator, intensifies the severity of the traumatic impact and is often an impediment to recovery. Prior trauma exposure also matters; trauma is thought of as dose-specific, meaning that the greater the exposure to traumatic events, the greater the impact. Sometimes this can seem counterintuitive, as someone may have survived a trauma without presenting as symptomatic only to seemingly decompensate later on, often after an experience that does not appear to be as severe as what they have already lived through. This is not a sign of weakness, faking, or blowing things out of proportion. Trauma symptoms often have a delayed onset and might only present after some kind of triggering event. The symptoms and effects of trauma are discussed in the Trauma Symptoms and Effects tab.