the kingdom in your mind
Delusional disorder is a psychiatric diagnosis denoting a psychotic mental
disorder that is characterized by holding one or more non-bizarre delusions
in the absence of any other significant psychopathology. Non-bizarre delusions
are fixed beliefs that are certainly and definitely false, but that could
possibly be plausible, for example, someone who thinks he or she is under police
surveillance. For the diagnosis to be made, auditory and visual hallucinations
cannot be prominent, though olfactory or tactile hallucinations related to the
content of the delusion may be present.
To be diagnosed with delusional disorder, the delusion or delusions cannot be due to the effects of a drug, medication, or general medical condition, and delusional disorder cannot be diagnosed in an individual previously diagnosed with schizophrenia. A person with delusional disorder may be high functioning in daily life and may not exhibit odd or bizarre behavior aside from these delusions. The Diagnostic and Statistical Manual of Mental Disorders (DSM) defines six subtypes of the disorder characterized as erotomanic (believes that someone famous is in love with him/her), grandiose (believes that he/she is the greatest, strongest, fastest, most intelligent person ever), jealous (believes that the love partner is cheating on him/her), persecutory (believes that someone is following him/her to do some harm in some way), somatic (believes that he/she has a disease or medical condition), and mixed, i.e., having features of more than one subtypes. Delusions also occur as symptoms of many other mental disorders, especially the other psychotic disorders.
The DSM-IV, and psychologists, generally agree that personal beliefs should be evaluated with great respect to complexity of cultural and religious differences since some cultures have widely accepted beliefs that may be considered delusional in other cultures. Specifically, to be a "delusion," a belief must be sustained despite what almost everyone else believes, and not be one ordinarily accepted by other members of the person's culture or subculture (e.g., it is not an article of religious faith).