depersonalization disorder
[DSM-IV] a dissociative disorder characterized by one or more severe episodes of depersonalization (feelings of unreality and strangeness in one's perception of the self or one's body image) not due to another mental disorder, such as schizophrenia. The perception of reality remains intact; patients are aware of their incapacitation. Episodes are usually accompanied by dizziness, anxiety, fears of going insane, and derealization.
Medical dictionary.
2011.