An 18 year old boy came to the Psychiatry OPD with a complaint of feeling changed from inside. He described himself as feeling strange as if he is different from his normal self. He was very tense and anxious yet could not point out the precise change in him. This phenomena is best called as:

The given history is the classical description of depersonalization. Depersonalization Disorder (DPD) - Persistent or recurrent experiences of feeling detached from one&;s mental processes or body, as if an observer Depersonalization causes significant distress or impairment in social, occupational, or other functioning During the experience of depersonalization, reality testing remains intact, one is aware of his/her experiences are unusual The depersonalization experience does not occur during the course of another mental disorder and is not due to the physiological effects of a substance or a general medication Ref :American Psychiatric Association, 2000