Depersonalization is in that case unconsciously used to decrease the intensity of unpleasant experience, whether that is something as mild as stress or something as severe as chronically high anxiety and post-traumatic stress disorder. The decrease in anxiety and psychobiological hyperarousal helps preserving adaptive behaviors and resources under threat or danger. Depersonalization is an overgeneralized reaction in that it doesnt diminish just the unpleasant experience, but more or less all experience – leading to a feeling of being detached from the world and experiencing it in a more bland way. An important distinction must be made between depersonalization as a mild, short-term reaction to unpleasant experience and depersonalization as a chronic symptom stemming from a severe mental disorder such as PTSD or dissociative identity disorder. Chronic symptoms may represent persistence of depersonalization beyond the situations under threat. Treatment
Treatment is dependent on the underlying cause, whether it is organic or psychological in origin. If depersonalization is a symptom of neurological disease, then diagnosis and treatment of the specific disease is the first approach. Depersonalization can be a cognitive symptom of such diseases as amyotrophic lateral sclerosis, Alzheimers disease, multiple sclerosis (MS), or any other neurological disease affecting the brain. For those with both depersonalization and migraine, tricyclic antidepressants are often prescribed. If depersonalization is a symptom of psychological causes such as developmental trauma, treatment depends on the diagnosis.
Description
Individuals who experience depersonalization feel divorced from their own personal self by sensing their body sensations, feelings, emotions, behaviors etc. as not belonging to the same person or identity. Often a person who has experienced depersonalization claims that things seem unreal or hazy. Also, a recognition of a self breaks down (hence the name). Depersonalization can result in very high anxiety levels, which further increase these perceptions.Depersonalization is a subjective experience of unreality in ones self, while derealization is unreality of the outside world. Although most authors currently regard depersonalization (personal/self) and derealization (reality/surroundings) as independent constructs, many do not want to separate derealization from depersonalization. Prevalence
Depersonalization is a symptom of anxiety disorders, such as panic disorder. It can also accompany sleep deprivation (often occurring when experiencing jet lag), migraine, 
epilepsy (especially temporal lobe epilepsy,complex-partial seizure, both as part of the aura and during the seizure), 
obsessive-compulsive disorder, severe stress or trauma, anxiety, the use of recreational drugs 
—especially cannabis, hallucinogens, ketamine, and MDMA, certain types of meditation, deep hypnosis, extended mirror or crystal gazing, sensory deprivation, and mild-to-moderate head injury with little or full loss of consciousness (less likely if unconscious for more than 30 minutes). Interoceptive exposure is a non-pharmacological method that can be used to induce depersonalization.In the general population, transient depersonalization/derealization are common, having a lifetime prevalence between 26 and 74%. A random community-based survey of 1,000 adults in the US rural south found a 1-year depersonalization prevalence rate at 19%.