We have seen from previous articles that I have published on this site that individuals can physiologically respond to severe and chronic trauma in two opposing manners: by becoming FLOODED (hyper-aroused and over-reactive) or by becoming DISSOCIATED (hypo-aroused and under-reactive).
Which Is More Common: Flooding Or Dissociation?
A study carried out by Lanius et al. involved trauma survivors having their brain activity measured (using fMRI machines) whilst being read a script that described the trauma that they had experienced.
As alluded to in the opening paragraph, it was found that their brains reacted in 2 ways which I briefly describe below :
1) THE ‘FLOOD’ RESPONSE :
Individuals who became flooded and re-experienced their traumatic experience showed reduced activity in the parts of the brain (the rostral anterior cingulate and medial prefrontal cortex) that dampen down emotions like fear. Therefore, these brain regions’ ability to dampen down the individual’s feelings of fright and terror were impaired (thus allowing these unwelcome sensations to run amok and create a state of hyper-arousal, including flashbacks and intrusive memories).
Correspondingly, these individuals also showed increased activity in the amygdala (a region of the brain associated with feelings of fear) and the right anterior insula (a region of the brain associated with awareness of body states). These responses, too, led to elevated feelings of fright and terror as well as an intensified experiencing of the bodily sensations that accompany such feelings.
2) THE DISSOCIATIVE RESPONSE :
Individuals displaying the dissociative response showed the opposite brain reactions. In other words, the brain regions that dampen down feelings like fear became MORE active thus reducing feelings of fear. Whilst this might sound good, the problem is that when individuals respond in this dissociative fashion, their emotions are ‘turned down’ too much, leading to feelings of emotional numbness / emotional deadness.
Which Of These Two Responses Was The Most Common?
It was found that 70% of participants showed the FLOODING response and 30% showed the DISSOCIATIVE RESPONSE. However, further research needs to be conducted to determine what proportion of individuals predominantly react to trauma by displaying either the flooding or dissociative response and what proportion react to trauma by displaying both responses (i.e. oscillating between the two). It is currently believed that most individuals respond in the latter manner (i.e. by oscillating between states of feeling flooded and states of feeling dissociated).