The document discusses depersonalization disorder (DPD), including its clinical features, causes, symptoms, and treatment approaches. DPD is characterized by persistent or recurrent experiences of feeling detached from one's mental processes or body. It is estimated to affect about 2% of the population. Common triggers include trauma, substance use like marijuana, and extreme stress. Symptoms include feelings of numbness, changes in perception, and derealization. Treatment focuses on reducing anxiety and distress through cognitive behavioral therapy and exposure techniques. Mindfulness-based approaches may also help by increasing present-moment awareness.