A 17-year-old appears in a clinic. His parents explain that he has stopped taking showers and become increasingly isolative in recent months, seeming to have lost all motivation and drive. The young man complains that his neighbors have all become part of a plot to kill him, and that he is hearing voices. You notice that he tells you these things with a flat affect. What diagnosis best fits this young man's clinical symptoms?
Organic
Disorders of thought and perception
Anxiety disorders
Mood disorders
None of the above