ABSTRACT
This chapter gives an overview of the conditions that can be confused with what is traditionally called functional psychosis, the forms of psychosis which have been defined in earlier chapters. The essential difference is that the symptoms result from an identifiable organic disturbance or from damage to the central nervous system (CNS). The concept of delirium is used to cover these conditions both in DSM-IV and ICD-10. In Scandinavia it is closely associated with delirium tremens and ‘confusion’ is often used as a synonym.
