There are exciting developments in our collective understanding of the human brain and how it appears to be programmed to keep us alive and safe. Experts now understand that the safety mechanisms within the brain are influenced by experiences of safety/lack of safety as we grow. Poly-Vagal Theory contends: when certain structures deep within the brain (eg: the thalamus, hippocampus, amygdala) detect information linked to a previous distressing experience, they take control and generate a response designed to keep us safe (eg: running way, punching out, yelling; or by hiding, staying silent, or doing what is expected of us instead of what we want).
Experts including Bessel van der Kolt and Gabor Mate believe trauma is held in the body, not in the event. Its our mind's memory of the event, and the body's ongoing protective response to to the event(s) that keeps us stuck in unconscious patterns of survival. The mind and body hold on to the physical and emotional experience of the event so that they are immediately ready to activate a protective fight flight response whenever they detect information similar what was experienced when the original event.
Trauma experts now believe anxiety, depression, post traumatic stress, and phobias occur as a result of the fight flight 'response button' being 'stuck on' for long periods of time. When the body and the mind start to become exhausted by the effort of unconscious protection, a range of psychological (eg: avoidance, tearfulness, irritability) cognitive (eg: reduced concentration, forgetfulness) and/or physical (eg: pain, fatigue, headaches, tummy upset) can arise. When these symptoms persist and cluster together we tend to identify them with names like 'anxiety' or 'depression'.
The symptoms elicited are variable, but tend to be influenced by the nature, intensity, and chronicity of events as well as our genetic history and predisposition. When the distressing event is a big 'T' trauma event, the 'alarm' eliciting the fight flight response might be registered by the body as loud and urgent, and the person might experience sudden surge of anxiety that stops them in their tracks (eg: panic, PTSD). When distressing events are subtle and constant across time the 'alarm' eliciting the fight flight response might be less noticeable and feel more like self doubt or low confidence. In this instance we might make small adjustments toward safety (eg: do what we are told rather than say no because if feels safer) and as we grow from childhood to adulthood these subtle safety responses become habits. Sometimes we identify ourselves through these protective behaviours (eg: Its not safe for me to speak up because what I think does not matter).
This new understanding of trauma has led to the development of new and exciting psychological treatments. Experts have learned that we can now heal from the impact of trauma, and resolve symptoms generated by trauma by 1) helping the body to learn the event is over and the person is now safe, and 2) providing the person an experience of psychological empowerment.