Depersonalization (or depersonalisation) is a malfunction or anomaly of the mechanism by which an individual has self awareness. It is a feeling of watching oneself act, while having no control over a situation.[1] It can be considered desirable, such as in the use of recreational drugs, but it usually refers to the severe form found in anxiety and, in the most intense cases, panic attacks. A sufferer feels they have changed and the world has become less real, vague, dreamlike, or lacking in significance. It can sometimes be a rather disturbing experience, since many feel that, indeed, they are living in a "dream".

Depersonalization is a subjective experience of unreality in one's sense of self, while derealization is unreality of the outside world. Although most authors currently regard depersonalization (self) and derealization (surroundings) as independent constructs, many do not want to separate derealization from depersonalization.[2] The main reason for this is nosological, because these symptoms often co-occur, but there is another reason of great philosophical importance, namely, that the phenomenological experience of self, others, and world is one continuous whole. Thus, feelings of unreality may blend in and the person may puzzle over whether it is the self or the world that feels unreal.

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Note added at 9 mins (2009-10-09 08:44:50 GMT)
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This is the term used in psychology.

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Note added at 32 mins (2009-10-09 09:08:14 GMT)
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تبدد الشخصية Depersonalization وفيه يعاني المريض تغيراً في إدراكه لذاته بحيث يفقد الشخص العادي مؤقتاً شعوره بالواقع وبالذات ( أشعر وكأني خارج جسدي أراقب نفسي ) . كما يكون هناك عادة شعور باللاحقيقة ( لا يبدو لي العالم حقيقياً).

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