What causes dpafu? Physical explanations: What does the brain have to do with it?

In keeping with other researchers, we think that depersonalization represents the activity of a protective ‘reflex of the mind’, or an automatic response, which is usually activated in threatening situations where the individual does not seem to have any control. We believe that this mechanism inhibits the ‘emotional’ brain, in order to protect the individual from the confusing effect that extreme levels of anxiety can have on our mind and behavior. For instance, it is known that at high levels of anxiety people can act in a reckless manner. This only hampers our ability to cope with threatening situations.

Here’s an example. Picture someone involved in a very traumatic, life-threatening incident such as a natural disaster. In this situation, a person may feel so terrified and overwhelmed that they are unable to think coherently, protect themselves or escape. Imagine instead what would happen if they were able to become ‘emotionally numb’ for a short period. This might be much more helpful. Rather than becoming overwhelmed and unable to function, they would be able to act calmly and leave the situation. However, they may also have a sense of unreality and feel as though they are in a dream, both during the experience and for some time afterwards.

It is possible to scan and take images of the brain while a person is experiencing certain feelings or trying to do various tasks. This shows which bits of the brain are or are not working – or are working too much or too little. Recent brain-imaging findings show that a group of brain structures known as the ‘limbic system’ (also known as the ‘emotional brain’ and made up of parts of the temporal lobes and deep structures in the front and centre of the brain all connected together in a kind of circuit) play an important role in labelling the things we perceive with emotional significance. This ‘emotional tag’ determines the type of emotions we experience in response to situations, objects and people around us, but also colours the way we perceive and experience things. So in addition to knowing or recognizing the things we see or hear around us (knowing that this object in front of me is a tree, a person, a telephone etc.), we also have a feeling of ‘emotional recognition’ (I like this object; I recognize this person; that thing frightens me, etc.). This in turn determines our feelings of being part of the world, and the way we experience reality. Any disruption in this process could lead to a significant change in the way we experience ourselves and our surroundings – it could, in other words, lead to feelings of unreality.

Brain imaging studies have shown that people with depersonalization disorder do not show the usual level of activity in the emotional brain when they look at unpleasant pictures. Likewise, the bodily responses that indicate emotional arousal (an example would be sweating) are unusually small and slow in people with depersonalization. Some work has also suggested that the hormones that are usually released into the blood stream in response to stress (such as cortisol) are also reduced in people with depersonalization – although not all laboratories find this pattern. All in all, this evidence seems to suggest that people with depersonalization disorder have an oversensitive emotion-suppressing mechanism. This may be because the mechanism was put to use early on in their lives, or because it was triggered by stress or a drug. Or maybe some people are just born this way. No one really knows.

We think that this ‘protective’ depersonalization response was intended by nature to be brief, and for it to last only as long as the perceived threat (as in the above example of a life-threatening trauma). However, in people with continual and recurring sensations of DPAFU this response becomes persistent and unhelpful. We have also gathered evidence that suggests that giving what psychologists call a ‘catastrophic meaning’ to this temporary response (e.g. ‘There must be something wrong with my brain’; ‘I must be going mad’ etc.) can lead to it continuing. DPAFU itself then becomes a threatening event, which triggers more DPAFU and so on, setting up a vicious circle that maintains the condition.