Delusional (paranoid) disorders: etiologic and taxonomic considerations. I. The possible significance of organic brain factors in etiology of delusional disorders.

The term "Paranoid Disorders" is used vaguely and indiscriminately by many authors. This article provides brief working descriptions of a small number of paranoid/delusional conditions and, making reference to the author's series of monodelusional disorders, describes certain organic brain factors which appear to be surprisingly common in the background of these cases. It is hypothesized that the group of paranoid/delusional disorders may be linked to schizophrenia, especially of the paranoid type: however, in the paranoid/delusional disorders, hereditary schizophrenic factors may be weak and adverse organic brain factors relatively much stronger.